Motor Age is the nation's oldest automotive trade publication and the mission of "advancing the automotive service professional" is one that I've tried to keep foremost in mind as I perform the role of technical editor. In the last eight years, I've been fortunate enough to recruit some of the best trainers and technicians in the nation as contributors and I'm proud to announce the addition of yet one more — Scott "Gonzo" Weaver.
Motor Age is proud to welcome Scott "Gonzo" Weaver as its newest contributor. Look for Gonzo's debut article in this month's issue.
Many of you may already know Gonzo. He's an ASE Master Technician and owned his own repair shop, Superior Auto Electric, for over 30 years before selling and semi-retiring in 2017. He has written articles for other industry publications and is the author of "Hey Look, I Found The Loose Nut!", a humorous collection of stories based on his experiences as a tech and shop owner. We hope you'll enjoy his debut feature, “The ABCs of electrical diagnostics,” in this month's issue!
Bringing you training opportunities like never before!
Eight years ago, I started the Motor Age YouTube channel and began producing monthly technical features you may know as "The Trainer" video series. To date, there are over 80 videos in that playlist alone. As of this writing, the channel itself has over 300 titles and nearly 30,000 of you have subscribed so you'll be the first to know when new content is added. (If you haven't subscribed yet, why don't you do that now by logging on to our channel at http://www.youtube.com/MotorAgeMagazine?)
The main reason I became involved with YouTube, Facebook and other social media platforms was simple. I wanted to reach out to the nearly 3/4 million technicians this country employs in a way that would complement the print issue, and make those same resources available to as many of you as I could. Having wrenched for over 35 years, I understand how tough our business can be and how hard it can be to get the training and technical information you need to deal with the latest systems and technologies.
A natural outgrowth of that effort was the partnership we formed with Technicians Service Training, better known simply as TST, and their president G. Jerry Truglia. G. has been active in aftermarket training since the early days of OBD and OBD II and is still among the top trainers in the country. Together, we've been hosting "live" webinars four times a year, bringing you technical training in a format that is still unique in the industry. We'll be hosting our first for this year about the same time you're reading this column with three more on the schedule for 2019.
Test, Don’t Get (And Get Answers Here)
It’s time to utilize guided component testing and other diagnostic tests including post-repair tests to make sure you are repairing a customer's vehicle right the first time.
And we both appreciate the support you've shown for these efforts. You've shared with us how useful these webinars have been for you at events we've attended all across the country. Many of you asked us for more such opportunities and, together, we've found a way to do just that!
For 2019, Motor Age has expanded on its relationship with TST. You may already know that TST hosts an annual training every year called the "TST Big Event" — an event that has grown substantially over the last few years and will be hosted again next month, March 30, at the Westchester Marriott in Tarrytown, New York. The Saturday event will feature back-to-back presentations by Kris Lewis, John Anello and John Thornton. It may be sold out by the time you read this but you can always check for open slots by logging on to www.tstseminars.org.
What you may not know is that TST is also known for the live training events it hosts for its area members in Massachusetts, Connecticut, New Jersey and New York. About six times a year, TST brings in nationally recognized trainers to present to their local membership. The fourth and final stop is in New York and is also simulcast online for those members who are unable to attend in person. Keep in mind that these are not scaled down versions of the classes these instructors present at the major events! It's the same material with the same ability to interact and ask questions. It's the next best thing to being there!
And now, with the support of TST, Motor Age is able to offer these same simulcasts on MotorAge.com! In fact, you may have already taken advantage of this new addition to our training offerings and participated in the first one we co-hosted, featuring our very own Brandon Steckler. Brandon led a great class on the use of pressure sensors and transducers as aids in troubleshooting drivability concerns this past January. Want to see the recorded version? You can still access it at MotorAge.com/pressureanalysis.
Wait, there's more!
In addition to expanding our range of technical training, I'm proud to announce that we are also hosting quarterly webinars with a management focus. I am proud to partner with Jeremy O'Neal, founder of AdvisorFix (https://www.advisorfix.com), in a series aimed at helping service advisors, shop managers and owners get paid for their services by teaching them sales techniques that work. Jeremy is especially well known for his sessions teaching attendees how to sell diagnostic time and as a former tech, I only wish my service advisor had received his training! We'll be hosting Jeremy's first webinar this month, so be sure to catch it when it's available!
(Image courtesy of Scott Brown) Among the first guests of "Shop Talk LIVE" was the founder and president of the Diagnostic Network, Scott Brown.
Another new effort I've taken on is called "Shop Talk LIVE" and is a live webcast hosted on the Motor Age Magazine Facebook page twice a month. By the time this issue hits your mailbox, I'll have completed six episodes, featuring industry influencers like Jorge Menchu and Scott Brown, and bringing you information and resources you can use to further your career as a technician or shop owner. I invite you to join me for our next episode and follow my efforts by following our FB page! It's all about keeping our conversation going and "advancing the automotive service professional!"
The demand on the vehicle's battery is increasing as technology continues to move us toward an all-electric future. Start/stop systems place additional loads that adds additional stress to the battery and modern charging systems are designed to supply just enough to keep the battery alive. Add to that the fact that modern electronics is less tolerant of weakness in the battery than ever before and you can see that it is important for us, as professional technicians, to be able to properly service and test them.
But what are the common mistakes we are making when servicing and testing batteries? What are the proper methods we should be employing? To find out, I talked to several industry experts and asked their opinions. Here's what I learned.
Be careful when taking your OCV measurements. If the reading is questionable, access the battery terminals/posts directly, especially on side post or remotely mounted batteries.
AGM or flooded?
According to Jim O'Hara of Clore Automotive, " The biggest issue we see when testing lead acid batteries...is being completely unable to identify the battery’s construction or misidentifying the battery’s construction. Digital testers rely on judgement maps for each of their testable batteries. Identifying an AGM battery as flooded or vice versa could yield inaccurate results." O'Hara adds, "If a battery is truly bad, it likely won’t matter, but if a battery is marginal, it very much will. Also, many technicians have trouble with the terms AGM and Gel, thinking that AGM batteries are Gel batteries. They are not. Finally, many technicians do not properly identify spiral batteries as AGM construction. Our testers have an AGM Spiral setting vs AGM Flat Plate setting to try to distinguish between the different types and make it clear to users that Spiral batteries are typically AGM construction."
My contacts at EnerSys, the makers of ODYSSEY batteries, echoed O'Hara's comments. "Identifying the type of battery the technician is dealing with is probably the biggest hurdle. Sometimes it is not clear what type of battery is in the vehicle, or what type of battery is supposed to be in the vehicle. Some vehicles come from the factory with an AGM battery, and must be replaced with an AGM battery. Gone are the days of buying the cheapest battery available that happens to fit. Always pay careful attention to the recommendation of the manufacturer. This not only applies to battery type, but also CCA rating. Never put in a battery rated for less than what was original equipment."
Properly identifying the battery design is also critical when it comes to maintaining the battery, whether it's the responsibility of the vehicle's charging system or your shop's battery charger. Patrick McLaughlin, Exide Technologies Product Manager-Transportation, offers, " AGM batteries do not have maintenance requirements, however, the charging profile is different than a conventional flooded battery. AGM batteries are more sensitive to overcharge due (to) the internal gas recombination cycle. Some battery chargers will have Flooded and AGM settings which essentially toggle the maximum charge voltage up or down to match each technology." It's easy, then, to understand that misidentifying an AGM battery as a conventional flooded design and trying to correct a low State of Charge (SOC) with your old, high powered, shop charger will actually cause more harm than good.
Speaking of SOC
We all understand that one of the very first measurements we need to take when assessing the condition of the battery is the Open Circuit Voltage (OCV). But is your OCV measurement accurate and what minimums are acceptable before proceeding with further tests?
Davis Knauer, Vice President Automotive Battery and Diversified Products Engineering for East Penn Manufacturing has this to say, "Accurate testing requires a minimum State-of-Charge level. A rested open-circuit voltage (that means it's been over 24 hours since the battery has been exposed to charging) of 12.4 minimum is required for load testing."
Make sure that the battery mounting is secure to minimize the impact of vibration on the battery. If any form of deflector or heat shield was originally fitted, be sure to reinstall them as well.
Where you test can also have an impact on your test results. If you just brought the car in and connected your meter or handheld battery tester to the battery's cable ends, your test results may be suspect. This is especially true if you're trying to test a remotely mounted battery using the jump points under the hood. According to the pros at Bosch, "(When a tester is hooked up to the battery cables, especially side terminals), corrosion on the underside of a terminal, unseen by techs, can prevent tester clamps from making good contact. Techs should always clean terminals and cables prior to testing or replacing a battery."
"Another issue can be with remote-mounted batteries, often found in vehicle trunks to save space under the hood. If techs test the battery using the underhood booster terminals, this may lead to falsely diagnosing a battery as bad. Additional resistance caused by the length of the cable can often result in inaccurate battery diagnosis. If a remote-mounted battery is tested and fails, techs should locate the battery and directly test it, to confirm if it’s an issue with the battery or if the issue is elsewhere."
"Testing failures in a vehicle must be confirmed after the battery is removed from the vehicle. Readings made while connected in the vehicle can be affected by poor connections, active loads, and effects from recent operation", added Knauer. The importance of connecting directly to the battery for accurate test results was echoed by nearly every expert I asked. I know I'll take a different approach from now on!
On to performance testing
I was first taught to use a carbon pile load tester to test the vehicle's battery. Later in my career, I was introduced to the handheld conductance testers that are popular (and required) by many OEMs. Today, personally, I prefer the use of a DSO (Digital Storage Oscilloscope) to test the battery. What do the experts have to say? Let's start with this great overview Knauer shared:
"LOAD TESTING: The gold standard for serviceability of engine starting batteries is a load test conducted according to the Battery Service Manual published by BCI (Battery Council International). A load of ½ the CCA rating is applied for 15 seconds. The voltage must not fall below a limit that depends on the core battery temperature at the start of the test. The battery must initially be at least 75% charged which correlates to a well-rested, open-circuit voltage of 12.4 or higher.
CONDUCTANCE TESTING: Conductance testers that correlate to BCI standard load test results are useful tools. They may provide a quick decision or they may say CHARGE AND RETEST. You may trade some accuracy for speed, but it is generally worth the time saved. The user must connect it properly, avoid putting in incorrect data to the tester, charge the battery properly before retesting when requested by the tester, and reconfirm failed results obtained in a vehicle after the vehicle connections are removed from the battery terminals and the terminals are cleaned. Proper connections to side or stud terminals REQUIRE that charging adapters be used properly.
(Image courtesy of Clore Automotive) Conductance testing is one of two acceptable ways to performance test the battery. Just be sure to properly input the test parameters - battery rating, type, etc.
DIAGNOSTIC FAST CHARGERS: These can be effective, but their potential to streamline the warranty process too much and not do more extensive testing must be weighed against the possibility of increased warranty and added replacement costs. Following recommended safety procedures (shielding, etc.) is a must when using these testers.
BATTERY SENSOR EQUIPPED VEHICLE: A battery sensor equipped vehicle continuously monitoring the battery should be able to make a much more informed decision than any quick test by a technician, but some level of secondary confirmation may be required for warranty situations on a case-by-case basis."
Exide's McLaughlin agrees, adding, "We (also) recommend the methods as outlined in the BCI Service Manual. The first is the carbon pile test. At 15 seconds if the battery is (less than) 9.7 volts, it should either be replaced or recharged and re-tested. Batteries greater than 9.7 volts can be returned to service. The second is a conductance test with one of the various meters available on the market. We recommend following the meter’s guidance on whether the battery is Good, Bad/Replace or Recharge and Retest. We do not advise making decisions solely on the estimated CCA rating output."
(Image courtesy of Clore Automotive) Still an industry standard, the carbon pile load tester should be used to "load" the battery to 1/2 of its CCA rating for 15 seconds — then observe the OCV reading. It should remain above 9.7v.
So I think what we've learned so far is that either testing method will provide us accurate results IF we insure that we are connecting our tools directly to the battery. If you take a quick test in the vehicle and it passes, you'll probably be ok but if the initial test is questionable, you'll need to remove the battery and test directly at the posts.
If the SOC measurement indicates a discharged battery, you'll need to identify the reason for the discharge. Today's charging systems are designed to maintain the battery properly and the only reasons for a battery to be discharged are age, faults in the vehicle's charging or electronic systems or extended periods of storage where the vehicle is not being used.
According to EnerSys, "When a vehicle sits for long periods of time, it can destroy the battery through repetitive deep discharges. Alternators are not deep-cycle chargers; their output is limited in operation. Elevated temperature can accelerate self-discharge and add to the total rate of storage discharge."
This high alternator demand can also cause damage to the alternator itself over time and it should never be relied upon to replenish a discharged battery. If your customer stores his/her vehicle for extended periods of time, recommend the use of a home battery maintainer to protect the battery and alternator from harm and premature failure.
In addition to the effects of extended storage, EnerSys shares, "Many times issues with a vehicle’s electrical system are automatically blamed on the battery. It is true that changing the battery is the easiest thing to do to start diagnosing an electrical problem, but that may not be the actual source of the problem. An example is when a parasitic load is causing battery and/or starting problems. Replacing the battery will only mask the problem temporarily. Taking the time to see why a vehicle may have trouble starting, or why a battery is constantly failing is key."
Better yet, make sure the battery has indeed failed prior to replacement - especially if it’s one that is not that old! This may require the battery to be charged and retested. Just remember what the experts have told us, though, and let the battery acclimate to room temperature and "rest" for a minimum of 10-12 hours. If the "rested" OCV is still below 12.4, replace it with confidence.
And young or old battery, be sure to test the vehicle's charging system to insure the new battery has a shot at a long and happy life!
Don't forget the reset!
According to industry sources, there are over 9 million vehicles in the U.S. fleet that currently require some form of battery "reset" or "registration" when replacing the vehicle's battery.
(Image courtesy of Exide Technologies) AGM stands for "Absorbed Glass Mat" and has several distinct differences in design from a conventional flooded lead acid battery. One is in how the battery must be charged and failure to follow the precautions will lead to internal damage.
"Not performing battery reset functions can cause some vehicles to go into a weak battery mode that will affect the operation of non-critical electrical loads. This mode can be manually reset after replacing the battery via a tool connected to the OBD2 port. Not performing battery registration functions may result in short battery life. Some vehicles manage batteries differently as they age. They will also treat AGM and flooded batteries differently", says Knauer.
Bosch spells it out for us, by offering these notes, "Most stop/start vehicles will require an ECM update when a battery is replaced, to ensure the system works properly and the battery is being charged correctly. This includes newer vehicles from BMW, Mini and the Ford F-150, among others. The most important thing for techs to know or understand is that if they are replacing the battery on a start/stop vehicle, they should look for a battery reset procedure in their scan tool, or invest in a separate battery reset tool that is updated for newer model year vehicles."
They also shared some OEM specifics for the benefit of Motor Age readers:
Audi: many models require a battery information or battery replacement procedure, including popular models like the A6, A4 and many Quattro-equipped vehicles.
BMW: Most newer 1, 2, 3, 4, 5, 6 and 7 series vehicles require a Battery Exchange Register procedure to ensure a new battery is charging properly. Many BMW SUVs and Mini Coopers require this procedure as well.
Ford: The Battery Monitor System Reset procedure must be performed on many high-selling Ford models, including newer models like the F-150, Escape, Explorer, Fusion, Mustang, Taurus and many Lincoln models.
General Motors: Some Buick, Cadillac, Chevrolet and even Saturn models require a Battery Sensor Module Relearn or Battery End of Life Estimate Reset procedure.
Jaguar/Land Rover: Most 2009 – 2015 models require a Battery Replacement procedure be performed to protect a new battery from being overcharged.
Toyota: Most Toyota and Lexus models since as early as 2004 require a Battery Current Sensor Initialization procedure be performed after a battery replacement.
Volkswagen: The company’s most popular vehicles require a Battery Replacement of Battery Information/Replacement procedure post-battery replacement, some as early as model year 2000.
Volvo: 21 Volvo models and counting require either a Battery Replacement or Battery Replacement Second Battery procedure be completed to ensure expected battery life.
Other valuable tips
Our experts provided more information than I can fit in just one article. But there are still a few great tips and observations I think we need to squeeze in.
All of our experts feel that parasitic drain is becoming increasingly common. "This causes batteries to live much of their life in a “discharged” state, accelerating sulfation," shares O'Hara.
(Image courtesy of EnerSys) Side post battery designs can hid corrosion behind the battery cable connections and cause false test results. On both designs, make sure the connections are clean before reinstalling.
Sulfation is the formation of crystals on the surfaces of the plates and is also an issue for those of you who keep batteries in stock. Remember, they too are subject to normal discharge. Exide's McLaughlin says, "The electrical current is unable to break down the crystals on the plates, and the battery cannot be charged. This is the most common reason for warranty return and speaks to the need for good inventory control, product rotation and boost charge practices along the entire supply chain."
Another common point raised by our experts relates to the use of "memory saver" devices. East Penn's Knauer had this to say, " Vehicles and the people who drive them are relying more on the vehicle’s settings than ever before. Protecting these settings is a simple precaution that doesn't get used enough. The loss of settings can be avoided with the use of a Memory Saver device. If the vehicle retains adequate voltage throughout a battery replacement, memory items such as radio presets and many other settings can often be preserved. However, it’s important to note that since the memory saver keeps power in the system, the operator should be careful that the positive cable end doesn’t contact something that could ground it out."
And that's a common problem, as Clore Automotive's O'Hara pointed out. "The biggest thing we stress when a battery is removed is properly securing the cable ends, especially when a memory saver is used. In those cases, as you know, the cable ends are live. I have seen on iATN where a user posted that he had specific non-conductive “bags” that he used and placed over the cable ends each time a battery was disconnected. This should be taught in the VoTech schools and be made standard practice in the industry. It is brilliant and much needed."
Which leads me to the last, but not least, subject the experts stressed — safety.
"One of the first things we continually communicate to our customers who work around batteries is safety. Even though safety mistakes are hopefully not common, information about proper safety procedures is always important. When working with batteries one should always wear proper safety glasses. No one should ever smoke or have any type of open flame or create sparks by the battery. Always remove rings, watches, necklaces, or any other type of conductive jewelry. Always disconnect the negative terminal first and reconnecting it last. (This avoids sparks if a tool would ground to frame.) Always use appropriate shields when charging and/or load testing the battery", stresses Knauer.
Today, even removing the battery may require a specific process so read up on the procedure before you even open the hood. And learn a little from the experts. Make sure you follow the proper safety procedures when working around batteries, verify a failed battery with direct testing, and insure that the replacement battery has a shot by testing the vehicle for issues in the charging system or electronics - especially parasitic drain. Use the right battery for the application when selecting your replacement and be sure you tell the ECM you updated it if required.
The exchange of information and data has been key from the beginning of mankind. In order to make good decisions, one needs good information. Information exchange is imperative in order for the decision-making process to be carried out. The lack of information one has limits the decisions that can be made correctly. Just as you and I need information to make decisions confidently, so will the modern vehicle. In order for the modern vehicle to run and drive correctly, the information must be exchanged quickly with accuracy.
In order to exchange information, you must have a transmitter, a medium and a receiver. When we communicate with one another we use sound. When you speak, you become the transmitter; the air becomes the medium; and the person you are speaking to becomes the receiver. Since you can both speak and listen, you are a transceiver. In the modern vehicle, information exchange will occur using electricity. When a module speaks (transmits) it becomes the transmitter; the wiring becomes the medium; and the module that the message is sent to becomes the listener (receiver). Therefore, if the module can transmit and receive it is a transceiver. Thus, using electrical on-off signals allows information to be transferred through the wiring between various vehicle modules.
Figure 1
This on-off digital information is sent at different speeds on different bus networks within the vehicle. Since each communication speed will use different rules on different networks, a means will be needed that allows communication between various vehicle networks. This will be accomplished by having a common module that connects each of these networks together. This common module is referred to as a gateway or bridge and is illustrated in Figure 1. The gateway has each of the different network communication transceivers within it. In this way the gateway will isolate the different networks from one another, while bridging the communications between the different modules. In order to gather data from the vehicle, an interface is used. This interface or scan tool will allow a connection to the vehicle networks. Once a connection is established with the vehicle data can be transmitted and received by the scan tool. If there are communication problems or no communications present you will need to connect to the communications wiring with an oscilloscope in order to test the circuits.
Figure 2
It is important to check a wiring diagram in order to understand how the scan tool will interface with the vehicle under test. In Figure 2, a block diagram of one method used to interface with the vehicle is illustrated. In this example, the scan tool is connected to the gateway module (CEM). It is important to understand that in this configuration the scan tool can be connected to the system by two different methods. In the first method the scan tool interface is not connected directly to the vehicle network. If the engineering team that designs the vehicle network deems it is necessary to protect the network from the scan tool interference, the gateway will isolate the scan tool interface from the network. The gateway when used in this method will bridge the scan tool communications to the vehicle networks. This means the data that is exchanged from the Diagnostic Link Connector (DLC) to the scan tool is not on the vehicle network. So, if you were to check these signals with an oscilloscope these signals are not the vehicle network communications, but the scan tool communications. In this case you will need to connect the oscilloscope directly to the vehicle network wiring under test.
With the second method, the gateway will connect the scan tool interface to the vehicle network. This will allow the scan tool interface to directly access the vehicle communication network. If an oscilloscope is connected to the DLC the data that is displayed on the oscilloscope is the data that is being exchanged on the actual vehicle network. When diagnosing the vehicle network, it is important to understand that these two methods are different. If one did not understand this you may connect to the gateway with the scan tool and see communications exchange on the oscilloscope and think the system is working. Where in actuality the scan tool communications to the gateway is all that is being displayed. In order to know which system you are working on, connect the oscilloscope to the DLC and the wiring at one of the modules. If the oscilloscope display shows two different waveforms then the gateway is isolating the scan tool from the network. If the oscilloscope displays the waveforms and they overlaying one another then the scan tool is directly connected to the network. If the DLC wiring is not connected to a gateway but connected directly to the network wiring then the scan tool will be connected directly to the network.
If there are communications between the vehicle and the scan tool, and there are communications codes set, get all codes from all of the modules. This will include the codes from the high-speed network, medium-speed network and low-speed network. Now that you have the codes, look over the codes to see if there are similarities between the modules of the same network, and if there are similarities between the codes from different networks. Now you will need to become a detective and analyze the data at hand. For example, if the high-speed network (engine and transmission) has anti-lock brakes (ABS) module codes set, the medium speed network (driver information module) has ABS codes set, and the low speed network (windshield wiper system) has ABS codes set, then the ABS system is the most likely culprit. In this example all of these systems need the vehicle speed in order to operate. In many of the communication problems on the vehicle there will be many different codes set. It will be important to relate each code that is produced and to try to find some commonality between them.
Figure 3
The low-speed network will most likely use the Local Interconnect Network (LIN). This network is a master slave scheme. This means that the main control module (e.g. CEM) that the other modules connects to is the master and all the other modules are slaves. The LIN communication protocol is based on the SCI (UART) data format, which uses a single-master/multiple-slave concept, on a single-wire (plus ground) 12 V bus. The clock synchronization for nodes does not have a precise time base (e.g., without a crystal or resonator) but uses a capacitance resistive timing circuit that lowers the cost of each module. Therefore the codes will be stored in the master module. An example of a LIN waveform is shown in Figure 3.
Once a module is suspected, the electrical circuit will need to be tested. This will need to be done with an oscilloscope. In order for a module to communicate it will only need the powers, grounds and communication wires. The testing will need to be at the suspected module connector and will check the power source at the module, the ground source at the module and the communication wiring at the module. It is important to know what the communication network waveform you are working on should look like. When you are scoping a high-speed Controller Area Network (CAN) system, the waveform is recessive (idle) at 2.5 volts and dominant (active) at 3.4 volts CAN-H and 2.4 volts CAN-L. Figure 4 shows the CAN high speed waveform.
Figure 4
CAN High Speed is a Carrier Sense Multiple Access with Collision Resolution (CSMA/CR) communication network system and uses two opposing voltages to reduce noise emissions. These voltages are carried on a two-wire medium referred to as a balanced signal scheme. Each wire carries a voltage signal that occurs at the same time at two different voltage levels. By having one voltage level rise and the other voltage level fall, they will cancel each other’s noise emissions. CAN High Speed uses a twisted pair of wires; CAN high line (CAN-H) and CAN low line (CAN-L). These wires carry differential signal transmissions. The twisted wires reduce Radio Frequency (RF) both received and transmitted. RF is any of the electromagnetic wave frequencies that lie in the range extending from around 20 kHz to300 GHz, roughly the frequencies used in radio communication.
Figure 5
Another common CAN system used in vehicles is CAN medium speed Single wire. CAN Medium Speed uses voltage that is carried on a one-wire medium. The voltage is recessive (idle) at low voltage and dominant (active) at high voltage, as shown in Figure 5. The CAN medium speed Single wire system is a carrier Sense Multiple Access with Collision Resolution (CSMA/CR) communication network.
The most common communication network systems used in the modern vehicle are: CAN high speed, CAN medium speed and LIN low speed. (For more information on CAN read “Understanding Control Area Network,” May 2016). All of these network systems use voltage changes over time to communicate their messages. Since the messages are based on voltage changes it is important to use an oscilloscope to check the basic voltage patterns produced. When using the oscilloscope it will not be necessary to check the message packets to the bitwise format. The bitwise format is the length of time each bit is recessive or dominant. These changes over time indicate the message to other modules on the network. These time intervals, for each bit, can be different for each system. Additionally they can change from manufacture to manufacture due to the CAN transceiver being programmable for different bit times. Thus, each time interval indicating a bit can be changed from system to system. Therefore these message packets are proprietary to the manufacture and are not shared in the light-duty market. To follow the bits within a data frame and have any understanding of what the message packets are communicating would be impossible if you did not have the code that was being used. One such example would be if you were testing a telegraph system with an oscilloscope. You would be able to see the voltage changes over time, but without having the code (e.g. Morse) that was being transmitted you would not understand the message that was produced. Therefore, it will not be necessary to read the message to the bitwise resolution, but to check the basic voltage patterns produced. The modules on the network are programed to understand the bitwise resolution of each data frame, so utilize the other modules to help diagnose the network under test.
Now that we have knowledge of what to expect when analyzing these network waveforms, let us analyze several other waveforms that you will encounter when working on CAN high-speed networks. These are the basic waveforms that you will need to know.
Figure 6
The first Can high-speed network waveform, shown in Figure 6, is produced when the ignition switch is turned to the accessory position “Accessory Mode” (on some systems) or when the system did not fully wake up. This can also be caused by power or ground issues. In this example, the waveform does not move in opposite direction from 2.5 volts as shown in Figure 4, but instead moves from 1.8 volts to 3.6 volts. This accessory mode waveform is one where you may not be able to communicate with the high-speed bus using a scan tool. In this mode there is still data transmission contained in each frame. In some cases, you may be able to communicate with just one module on the bus such as the transmission control unit.
Figure 7
The Second CAN high speed network waveform is shown in Figure 4 and is produced when the ignition is turned to the on position or “Active Mode.” This is the normal CAN high speed network waveform. The third CAN high speed network waveform is shown in Figure 7 and is produced when the Ignition is turned to the off position “Sleep Mode.” In this example the waveform does not move in opposite direction from 2.5 volts as shown in Figure 4, but instead moves from 1.4 volts to 3.6 volts with minimal data transmission.
Figure 8
The third CAN high-speed network waveform is shown in Figure 8 and is produced when the termination resistors are missing. The high-speed CAN Bus must have termination resistance in order to work properly. Without the proper termination resistance, the bits will not be formed correctly and will create a problem with the message bit timing. If no or low resistance is in place the bus will have reflections. Reflection or ringing can create poor to no communication problems. This can be caused by missing resistors, broken wiring or when one disconnects the module connector and breaks the communication lines to the network. If you are unplugging modules while monitoring the oscilloscope display to locate the communication problem and the communication lines go into and out of the module, then you must bridge the CAN-H to CAN-H and CAN-L to CAN-L wiring at the connector. This will keep the communication wiring intact to the other modules in the system.
There are two 120 Ω termination resistors in the bus lines. These are placed between the CAN-H and CAN-L bus lines. The resistors can be in the modules, fuse panels, or in the wiring so check a wiring schematic for their location. To test the resistance of the CAN termination resistors, there must be no power on the network (sleep mode). Ohm the DLC from pin 6 to pin 14, the resistance should be approximately 62 ohms. If the communication lines connect to the gateway (e.g. CEM) and the gateway isolates the DLC from the CAN high-speed bus; then if you were to measure the bus resistance at the DLC you are not measuring the actual CAN high-speed communication lines. In this case, back probe the communication lines at a module on the high-speed network.
Figure 9
The fourth CAN high speed network waveform is shown in Figure 9 and is produced when the In-Frame Response (IFR) or Acknowledgement (ACK) is missing. The ACK is a message that is embedded in the data frame by a module other than the original transmitter. This is to let the transmitter know that some other module on the network received the message. If the ACK is not received, a form error in the data frame is set. This means that the message is resent over and over until an ACK is read by the transmitting module. This is why the CAN message on the oscilloscope display is repeated over and over and usually caused by broken communication wiring. In this condition the module is not on the network but is isolated from the network.
Figure 10
The fifth CAN high-speed network waveform is shown in Figure 10. This is produced by a common problem where a CAN transceiver is failing. This occurs when the voltage on the network is pulled high, as shown in Figure 10, or when the voltage on the network is pulled low, not shown. This can be an intermittent problem when the CAN transceiver first starts to fail or a hard failure where each time the module takes control of the network the signal voltage fails. The faulty module is located by unplugging the modules from the network while monitoring the oscilloscope display. When setting your oscilloscope settings always use strip chart roll mode at a speed where you can watch the bus messages stream across the oscilloscope display. If you use a trigger mode it can hide the problem entirely. When the correct module is unplugged the voltage failure will be gone. When the module is reconnected the voltage failure will return. Be careful here, if the module is failing intermittently it can reset once it is unplugged and loses power and ground, and can begin to work properly. Always be sure you can see the problem first, then disconnect the module from the network. If the problem is gone, this is the problematic module. Always test all of the powers and grounds before ever replacing any electronic device. When you remove the module electrical connector, check for contamination such as oil in the connector. Check all of the connecting pins for any damage. If you question the connecting pins connection use Stabilant 22, this is a liquid that helps with poor electrical connections.
On CAN high-speed systems, the module can be isolated from the network due to faults exceeding 256 error counts. Each node maintains two error counters: 1) Transmit Error Counter 2) Receive Error Counter. A transmitter detecting a fault increments its Transmit Error Counter faster than the listening nodes will increment their Receive Error Counter. This is because it is assumed there is a better chance that the transmitter is at fault. From 0 to 126 error counts the module sets active errors where it can destroy messages on the bus. This is accomplished with 6 dominate bits at the end of frame which violates the 5-bit stuff rule, and will destroy other bus traffic. When the Transmit Error Counter raises above 127 (e.g. after 16 attempts), module A goes Error Passive. The difference is that it will now transmit Passive Error Flags on the bus. A Passive Error Flag comprises 6 recessive bits (violates the 5-bit stuff rule), and will not destroy other bus traffic, so the other modules will not be affected by module A bus errors. However, module A continues to increase its Transmit Error Counter. When it raises above 255 error counts, module A takes itself off of the bus “Bus Off State.” A bus off state will require an extended bus idle period (not likely) or a battery reset to get the module back on the bus. So before replacing any module, first reset the network and test to see if you can communicate with this module. If you can now communicate with this module, realize that this module could be bad or could be in “Bus Off State” not because it is bad, but due to another module’s clock being bad. If one of the modules on the network has a clocking error it may not set any codes for itself but will destroy bus traffic thus setting codes for other modules. If this module with a bad clock destroys another module’s messages and the other module counts enough errors, this good module will take itself off of the network. Yet the module with the bad clock (bad module) will remain active on the bus. When a module with a bad clock is on the bus there will be multiple codes in most of the other modules except for the module with the clock error. The Controller Area Network is a great system and, with an in-depth understanding of how these communication systems operate, will come an understanding of how to diagnose these advanced communication systems.
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When I was at the Ford place, I drew a work order for a charging system fault on an old F-150 and told the customer she needed a new alternator – and she went and bought one from a local parts store – well, that one wound up being bad, so I yanked it off and she took it back, had it checked on their machine, and brought me another one. This happened four times – we finally got a good one, but she was kind of ill that she had to pay us to replace the alternator four times – thinking she’d save money buying her own part, she made a series of bad choices. Had those bad alternators come from our parts room, the Ford Authorized Manufacturer would have paid all that labor.
With these funky big tires contacting the splash shields during turns of more than about 15 degrees, this one is no fun to drive — but it wasn’t written up for that.
On a slightly different note, I used to hang out when I was off work at Sambos drinking coffee back in the late ‘70s with some of the locals in Port Arthur, Texas, and when I overheard one of the patrons asking a young waitress about her car, she told them she had a ’63 Buick Special but that the “motor had burned up” and she couldn’t drive it. I chimed in to ask if she had run it out of coolant or oil, and she told me it had caught fire under the hood while she was driving and had been sitting in her parents’ driveway for months.
She went on to say that they had given her a coil, a distributor cap and some wires for her birthday, but nobody they knew wanted to attempt the fix and they couldn’t afford to hire a shop to do it. I asked if I could take a look, and she agreed, so I dropped by her parents’ house and opened the hood on that little V6 to find that the engine fire had been wall to wall – the wire harness was little more than a bunch of bare wires, and the ignition components were, as expected, nothing but crust and ash. I wondered if I had bitten off more than I could chew; I couldn’t even tell where the fire had started or why, but I dove in headfirst.
Retrieving some rolls of wire I carried in my truck toolbox, I carefully unplugged the mostly melted wire harness from its various connection points and using cheap butt connectors and electrical tape (I wasn’t going to spend the time it’d take to solder and heat shrink everything), I rebuilt that underhood harness one wire at a time on the tailgate of my pickup, then plugged it all back in and installed her new distributor cap, wires and coil. I hooked up my jumper cables, we spun it over, and it fired right up and ran like a champ. The whole job only took a couple of hours, so I charged her $25, and she paid me with multiple rolls of coins from her tip money.
The Commander
A friend of mine brought his son’s 2006 Jeep Commander, 4.7L V8 with a 5-45RFE transmission and 187,854 miles on the odometer, telling me he believed water was making its way into the #8 cylinder, because the vehicle had overheated a few times and now it was misfiring on that one. We found his misfire on the cylinder he indicated, but a quick look at all the plugs didn’t show any evidence of coolant ingestion at all, only a sooty plug on the dead hole. So, my man Charles tossed a set of plugs in there, and in the process of our testing we discovered the compression was low on that cylinder. Further, Charles said that with it idling he was hearing something under the valve cover he didn’t like, and to get the valve cover off, he had to recover the refrigerant.
Any shop who doesn’t use a refrigerant identifier does so at their own peril. Without one, this kind of contamination gets spread from the recycler to other vehicles like a disease.
When we did the refrigerant I.D. with the Peter Coll Neutronics tester (a shop should always do that!), we got a big fat red FAIL light – 5 percent hydrocarbons in there, possibly from some fly-by-night canned stuff. We had to use our dedicated tank and machine to suck that garbage juice out. When Charles got the valve cover off (no fun), he found the rearmost roller rocker out of place and lying fallow on the head. How did this happen? Somebody else might know, but I don’t. We removed and collapsed the lifter so we could get the rocker back in without too much trouble, and that took care of the engine skip, but we weren’t finished – not by a long shot. More about that one in a minute.
The Buick
One of our staff drives a 2007 Buick Lucerne that was purchased from the local GM dealer as a very clean used vehicle, and it’s outfitted with that tried-and-true 3.8L V6 GM used for so many years. It had been sporting an MIL light for awhile along with a P0420 code, but the director in charge of our vehicles said the catalyst had already been replaced with an aftermarket unit before the car was purchased and he wasn’t concerned about that. What did turn out to be a concern after a few thousand miles was that the Buick died and came in on the hook with no fuel pressure.
The Director’s 2001 Toyota Tacoma hunting truck died when he was leaving his driveway that morning, and we initially diagnosed a bad fuel pump and then found this. He hasn’t owned the truck for very long – and this was done before he bought it.
It was interesting that about this same time, the 2001 Tacoma driven by the director died from a lack of fuel pressure as well. We ordered a Delphi fuel pump from the local parts supplier for the Buick and initially ordered a fuel pump for the Tacoma, but after we got the Toyota pump out, we found somebody had already replaced it (just the pump, not the whole thing) and did a crappy job on the in-tank wiring patch, so we got rid of the butt connectors, fixed the wiring the right way and sent the pump we had ordered back to the parts store to get the Tacoma done.
The good trace (top) shows when the Buick started and ran the way it was supposed to. The bad trace (note the down spikes at the top when the starter was operated) shows that spark and fuel pulse were initially absent on the long spin
One of my people rolled into the trunk on that Buick with an air ratchet and a fan blowing the fumes away and replaced the pump module with a new Delphi unit, but then about six weeks later, the pump died again, and this time, since we were between terms and I was off work, the Buick wound up at the GM dealer where it had originally been purchased – and the director called my cell phone to say that the dealer said the pump was bad. I called and explained to them that the pump was a Delphi pump, but they said since they didn’t sell that one to us, they’d need us to get a replacement pump from the parts store – which I did, and they installed that one – it was back on the road.
Well, the odd thing that happened next was that when the car was started after a hot soak it’d immediately die and would need to be re-started, and we found the second new fuel pump failing to hold rail pressure after the vehicle was shut down. A third replacement Delphi pump held rail pressure at shutdown, but sometimes the car would still pull that odd start-and-die stunt. This was getting interesting. Further, there were a couple of times when the car would either lose power or just quit while driving and fail to re-start, but we could never duplicate this. We DID, however, get it to start, die, and then spin about 10 seconds before starting, and we got it to repeat this somewhat regularly, if not every time. And while it had nothing to do with this start-die problem, we obtained a Walker bolt-on replacement cat to get rid of that annoying P0420 once and for all. And it did.
For the other issue, I broke out the Waekon Industries Flight Recorder® (WAE-45364), which is kind of pricey, but records ignition, fuel injector pulse, battery power, and one Auxiliary data plot of your choosing in an internal buffer when you tap the record button, and the graphs can be retrieved on your PC with the dedicated software.
We had successfully fixed a Chrysler Crossfire that had stumped the Chrysler dealer using this same tool (see “Methods, mysteries and frustration,” May 2013), so we used the tool on the Buick and found that, when the concern was duplicated with the auxiliary measuring power to the injectors, there was indeed power to the injectors. However, the spark and pulse weren’t consistent during the extended spin. After replacing the crank and cam sensors to no avail, we replaced the underhood fuse box because it has a gaggle of those integrated relays that can’t be replaced — one of them being the run/crank relay; if that relay doesn’t deliver power (or not enough power) to the PCM, we reasoned that it might cause this concern. It was a Hail Mary pass, but at the time of this writing, about six weeks has gone by with no further complaints.
The 2007 Silverado and the Fusion lug
This truck came in for a routine service and an oil leak, and when we applied the dye and the black light, we found the oil oozing out around the oil filler cap – which was peculiar, but not unheard of, particularly on these GM V8 truck engines that have the PCV system integrated into the driver side valve cover. The students who did the service also reported moisture in the crankcase, another indication of the PCV issue. We replaced the valve cover and those concerns evaporated.
At first, we put dye in the crankcase, then we got under the truck and saw the trickles of oil, which we tracked to the filler cap. That, coupled with the moisture in the crankcase, fingered the valve cover, which has the integral PCV. This one got a replacement valve cover.
On a side note, we found a Camry leaking oil from around the oil filler cap too, but it turned out that one just needed an oil filler cap.
We were doing a routine tire rotation on a 2012 Fusion when one of my people came to report that one of the lug nuts was spinning round and round on the left rear and they couldn’t get the tire off. That one was because of a nut that was initially cross-threaded and impact-forced right at its tip. This wasn’t the first one of these I had seen – we had an Altima with the same issue awhile back, and it was a bear. The folks who use an impact wrench with no torque stick tend to think that too tight is better than just right, and after a little of that, the threads begin to gall and sometimes the nut just won’t move. If the splines on the stud are sufficiently strong, the stud will break off. If not, they spin in the hub, like this one did, which becomes something of a problem.
I’ve seen this more than once — this lug nut was crossed up by somebody on the starting threads and then they tried to force it with an impact wrench, which effectively welded the lug nut to the stud. In other cases, the impact wrench distorts and galls the threads all the way down due to overtorqueing.
Oil drain plugs are prone to a similar kind of failure.
I used a two-pound hammer to drive an old MAC prybar in between the wheel and the hub with enough force so that we were able to foul the head of the lug stud and get the nut off, and then we replaced the stud and the nut. At my shop I teach them to spin the lugs on there with the impact on its lowest setting and then follow up with a torque wrench. Then I place the students in shops where all that careful torqueing (and even the practice of wearing safety glasses) goes out the window and they wonder why I even taught them that to begin with. Oh, well.
Back to the Commander – and a Dodge
In search of the overheating problem, we noticed that there were coolant stains on the exhaust back below the heater core area and we initially thought there might have been a heater core issue, but then, there was no coolant in the passenger side floor. Was this one of those with a secondary drain for a leaking heater core? No, there was a hose issue of some sort going on back there, and initially we found that one of the clamps was loose and dangling, but that wasn’t our leak either. What we found was that somebody had replaced an original heater hose tee with a plastic one that looks like it came from a hardware store – it was a size too small, not made for coolant heat, and was cracked to boot, and the clamps had egg-shaped the plastic. It’s a wonder it was holding coolant as well as it was.
First, we noticed the coolant drain stains, then, above that, the clamp somebody had never tightened. Finally, in a totally different hose, we found the cracked and lousy tee.
We replaced the tee, pressure tested the system, liked the results, and then drained the radiator, which didn’t have much coolant in it. On this one, because the thermostat is in the bottom radiator hose, you drain almost nothing out of the engine block unless you yank the ¼ inch pipe plug out of the side of the block to let it gurgle out of there – we did that. Afterward, I wanted a full load of 50/50 in there, and I poured it in through the upper radiator hose with a funnel to fully purge the engine block water jacket of air before we did anything else. Remember, the thermostat is in the lower hose. Toyotas, old VW Rabbits, and some other platforms are built this way. Incidentally, Ford’s 2.8L V6 was configured this way as far back as the ‘70s (think Mustang II).
Okay, so we fired up the Jeep and let it run for a while – there was a Check Engine light, and among some other codes, we got one for a cooling fan issue, and this had been an overheater – so we went back at it.
This is one of those Jeep vehicles that has a belt-driven fan AND an electric fan, and we noticed that somebody had pocketknife-shaved the cooling fan wires in spots, probably trying to see if there was power to the fan. We checked the fan electrically with a test light wired in series but found no open segments. Pulling both fan relays, we found no power at their common terminals, and that’s when we noticed that blown 50-amp fuse that probably happened when somebody was fiddling around with the fan wiring. With the fuse replaced and a smooth re-test, the fan came online and everything was dandy.
I like to dissect the fans that fail – usually the brushes are worn out, but this one (from the Charger) died because of a cold solder joint.
Speaking of Chrysler V8 overheating problems and customer bought parts, we had a 2006 Charger that came to us with a new radiator in the back seat that the owner had purchased online, along with specific instructions that we were to replace the radiator first – in true form, they had a friend of a friend do the troubleshooting and he told them that was what they needed. We followed those instructions (replaced the radiator) but we also did a pressure test, which revealed the actual problem — it had a leaking water pump, so we did that too. But once again, we weren’t done yet. In sewing that job up, we noticed the fan (a dual unit) wouldn’t run, and our test light test of the driver side fan motor revealed an open motor. With a new dual fan, a new water pump, and a new radiator, that ‘06 Charger was cool to go.
In this article on voltage drop (VD), we will explore what it is, how to check for it and share some vehicles that I have come across with VD issues. Let’s start with an explanation of VD so you can better understand what we are dealing with. Remember that there are many vehicle problems with a component or system not working right that can be traced back to a voltage drop. Have you ever noticed a vehicle driving down the road with one headlight that is not as bright as the other? How about a vehicle that has high LTFT numbers? A blower motor not turning fast enough, or a rear window defroster that partially clears the window? Well, if you answered yes to any of them you have experienced VD.
A dynamic problem found with a dynamic test
You should know that voltage drop = electrical resistance that we measure in Ohms and check dynamically by performing a voltage drop test with our volt meter. There are many connections on a vehicle that may contribute to a VD issue such as loose, stripped or crushed connections and broken wire strands. We cannot expect damaged wires or loose and dirty connections to provide the proper current flow or voltage. If all connections are not intact and well connected, the result will be unwanted resistance, and that equals a voltage drop. A VD problem will prevent the proper flow of current causing a starter motor, bulb, blower motor, solenoid or any other electrical device from performing as designed. In other words, VD results in the poor performance of a load.
Let’s consider a vehicle’s headlight that is dim even after it has been replaced. What is the next step in getting that headlight to operate correctly? We know that many techs have a Power Probe or if not, they at least have jumper wires that they can use to test the circuit quickly. This quick test is just that, a quick test that can be utilized at the load to see if the headlight will illuminate correctly. Take the Power Probe/fused jumper wires and apply power to the B+ side of the circuit and see if there is any noticeable change to the brightness of the headlight. If it helped or not, never think you’re finished until you apply ground to the negative side of the headlight. If the headlight now illuminates to the level of the other headlight, you now know that there was a bad ground but what you don’t know is how much of a voltage drop there was.
Now let’s try using a VD check the correct way so we can measure the exact amount of VD. First, we will start with the DVOM. The DVOM, when it is set to read voltage, measures the voltage potential between the two leads. Keep this in mind as you take your measurements so you can learn how to speak the language of the meter. Connect the leads to the battery positive and negative post. You should read the battery's voltage potential on your meter. On a healthy, fully charged battery, that potential will be 12.6 volts.
Figure 1
Next, leave the positive lead at the battery post and take the negative lead of the meter and go to the positive side of the headlight. With the headlight "on," the meter will measure the voltage potential (difference, or drop) in the circuit. In other words, all of the available voltage (that is, all of the 12.6 volts you measured at the battery) should be going to the headlight is being checked to make sure that it did indeed make it to the battery, give or take a couple hundred millivolts. This is followed by taking the negative test lead and placing it back on the battery negative post followed by taking the positive meter lead and going to the negative side of the headlight. The meter is still on the DC voltage scale and will provide the exact reading of the drop.
In this example, let’s say your meter reads 00.90 on the meter's 40/60-volt scale. How much of a voltage drop is the meter measuring? That’s right — 900mV. Let’s take a look of a voltage drop test on a vehicle since a picture is worth a thousand words. In Figure 1, we have our Power Probe connected to the vehicles battery and then connected our meter’s positive lead to the Power Probe positive tip (note the rocker switch is depressed to the positive position as indicated by the red light) while the meter negative lead is connected to the starter positive post.
An important thing to remember when performing a voltage drop is to always make sure that the load is "on." There will be no voltage drop if no current is flowing. In this case, I have my tech up in the vehicle so he can crank the starter over while the meter captures the voltage drop. The complaint on this vehicle was the engine cranks over slowly intermittently. Can you see why? Yes that 00.96 equals 960 mV, almost 1 volt on the feed/B+ side. Now how about the ground side?
Figure 2
Well as you can see in Figure 2, the reading there was 320 mV for a total voltage drop of 1280 mV or 1.28 volts. As we know, the battery has 12.60 volts before we crank the engine over. The voltage usually drops about a volt or so making the available voltage level about 11.60 minus our 1.28 voltage drop, only leaving 9.8 volts available. Now add in mechanical resistance from a cold motor or thick oil and "Bingo!" — we have a starting problem. Does that make sense? If not, as we continue on, we will have more real world examples to help you grasp the concept.
Essentially, a voltage drop test measures the reduction in voltage due to resistance (more than normal/excessive) in the circuit. It is impossible to get a 0v voltage drop on a working/complete circuit. A reading of up to 200 mV is permissible on a non-computer circuit, while when dealing with a computer component, 100 mV or less is permissible. To measure the small amount more accurately, scale your meter down to the mV scale. A couple of things to also remember is that there are 1,000 mV in 1 V. For example, 1.11V = 1,110 mV. When performing a voltage drop test on mV DC scale and the meter displays "OL," you definitely have VD and you need to take care of it!
Real-world examples of a thief at work
Our next example is checking a voltage drop on an engine with an open ground circuit (Figure 3) at the intake manifold. The volt meter leads are connected a little differently than what I described earlier when doing the starter circuit ground check. Here, the negative (black) meter lead is attached to the battery negative post and the positive (red) meter lead is connected to the engine’s intake manifold.
Figure 3
If you look at the battery negative post, you will notice that the cable is disconnected from the battery on purpose. The volt meter is reading 11.87 volts — equal to the battery’s voltage level.
If the two measurements are equal, there is 0v voltage drop. If our meter leads were placed in the same manner as our starter circuit test, the meter would read exactly that — 0v. Since everything in a circuit has some resistance, we should always measure a few hundred millivolts. A perfect reading like this indicates reveals the true reality. There is no current flow and no voltage drop, likely due to an open (or infinite resistance) between our two test leads.
A great use for voltage drop testing is testing for Parasitic Draw. Again, every component in an electrical circuit has some resistance and voltage will "drop" across that resistance, even if it's a small amount. But only if current is flowing, remember? And isn't that what we're looking for when chasing down a parasitic draw — something that is flowing current when it isn't supposed to? To use the voltage drop method (Figure 4), place the meter lead ends on the exposed metal blade tops with the meter set to mV. This method is not usable on all fuses but for this example we have fuses where the metal is exposed on the top. If the leads ends are connected correctly the meter will either read 0 or a mV reading as the one pictured. If the meter reading is bouncing all around (numbers not steady) you are not connected correctly to the metal of the fuse.
Figure 4
Important point to remember is that there is NO voltage drop if the load is NOT on. So, if the lead ends are connected properly you will either get an mV reading that indicates a voltage drop thus equaling a parasitic draw, or zero that means there is no draw.
Case studies
A Ford Explorer came in with a no start complaint that was traced down to a voltage drop. The vehicle owner had already replaced the battery and the starter motor before he had the vehicle towed in. While performing a voltage drop on the B+ side there was nothing abnormal, but it was another story on the ground side. The meter indicated a reading of 8-plus volts that was causing the no start condition on this Ford. We made a temporary ground cable so we could start the engine up and drive the vehicle into the bay. We attached both ends of the negative clamps from our jumper cables, placing one at the negative battery post and the other to engine block. With those connections, the engine cranked over and ran. Since the temporary cable worked, we knew that we had to check the negative cable. Take a look at this source of voltage drop! This major ground (Figure 5) is a common problem on many vehicles that have a battery that has an out gassing issue leading to cable corrosion.
Figure 5
A 2005 VW Jetta came in with another recurring issue — the fuse box (Figure 6) that is on top of the battery is melted. This has been a problem that goes back at least to the 2002 model year on VWs. A common mistake that is made is just replacing the fuse box and not finding the root cause of the problem. Each of the terminal wire ends needs to be checked very carefully for a VD. There has been an issue with the wire insulation not being totally stripped back from the factory that causes amperage to flow through less strands. The current flow through a small area of wire strands causes heat buildup due to voltage drop. Since the circuit is not designed to flow the high demand of current through a small connection, this causes the voltage drop. The most common terminal that causes the box to melt is the black wire that goes to the alternator, followed by the cooling fan terminal. Before you change the fuse box, it is recommended that you open up the terminal ends and make sure the connections have the full contact with the wire. The fix for this vehicle was new terminal ends with full contact of the wire strands, heat shrink and a new fuse box.
Figure 6
Our next case study is on a 2000 Volvo S80 came into our shop about 12 years ago with the complaint of no start, no crank and shifter locked out. Even though this is a case study from awhile back, it has very important information that can help bring a voltage drop issue to life. I sometimes use this case study when I am teaching a class to show a more advanced voltage drop problem. I believe that the information will help you to understand what VD can do beside prevent a motor, bulb or load not to function as designed. The vehicle owner stated the vehicle was starting and running normal until the no start issue appeared. We started our diagnostic procedure as we usually do, by asking the customer when it happens, if any work was recently performed, followed by a visual inspection.
Our visual inspection at first did not uncover anything unusual so we moved on to scanning the vehicle systems by connecting our Autologic scan tool. At the time the Autologic blue box Volvo software provided very good information along with vehicle programming capabilities. The scan tool uncovered a problem with no communication, so we installed our BOB (DLC Breakout Box) and checked for power at Pin 16 along with ground at Pin 4. The results of our voltage checks were normal, so before getting ourselves in too deep, we checked for TSBs and information in Identifix and iATN. Neither information sources had any published information regarding our problem. Since we came up empty handed, we looked in Alldata and ProDemand to check the wiring diagrams and traced them out. We found that the system we were working on was a CAN (Controller Area Network) system that meant that there could be something on the BUS that was preventing scan data from being transferred to the scan tool.
Figure 7
Next, we connected a labscope leads to Pins 6, CAN High and Pin 14, CAN Low (high speed CAN) looking for the normal square wave but that’s not what the scope displayed on the screen. We proceeded to check the Pins 3 and 11 that are a Low speed CAN network that are the communication lines for the CEM (Central Electronic Module) aka body module. The results that we found was the same issue, no square wave communication. When you look at the wire diagram (Figure 7) you will notice that the Low and High speed lines both go through the CEM making it the best place to start.
Figure 8
Our next step was to locate the CEM in Alldata then seek out its physical location under the left dash. Looking at (Figure 8) you’ll notice the burn at the pin connections caused by a poor connection, aka high resistance, resulting in voltage drop. Another problem that we uncovered was a water leak caused by clogged body drains. The clogged drains allowed a path for the water to drip right down on to the CEM connection not exactly helping our poor connection or possibly causing it. Our next step was to repair this problem by cleaning the drains making sure that no more water would be able to leak down on the CEM. We followed that up by cleaning the connections and applying Stabilant 22A to enhance them before we reinstalled the new CEM. After the physical repair was complete, we had to program the module with the Volvo software, so the engine would start. With the engine now running the only thing left was to check the gear shifter issue. We proceeded to move the shifter in all the different gears to make sure they all worked then test drove the vehicle. After the test drive was complete, we ran another vehicle scan of all modules making sure that everything was back to normal. The Volvo was now over the VD issue and was ready to ship out.
I hope this article has shed some light on VD and has helped you better understand one of the biggest problems that we facing diagnosing on today’s electronic load vehicles.
I was called to a shop to do a post-repair scan on a 2019 VW Golf (Figure 1) that was all finished and ready for delivery. This shop is a high-volume shop, and they move many cars in and out of the door and they make it their own policy to scan all cars when they are done just to get peace of mind knowing that vehicles are safe and free of any issues prior to releasing the car to the customer. The shop may not always get paid by certain insurance companies for doing post-repair scans, but it is to their benefit to prevent a comeback and an inconvenienced customer that may give bad feedback on the shop’s services.
Figure 1
When I arrived at the shop, the car started up fine and the only warning light that I noticed on was the yellow triangle caution sign (Figure 2). This was because I did not have my seatbelt latched while I was sitting in the driver seat. This caution triangle is commonly used by manufacturers to alert the driver to view the instrument cluster to look for issues with the vehicle prior to driving off down the road.
Figure 2
As I performed the vehicle scan, I came across 10 control modules with about 32 faults combined (Figure 3). Most of these faults were no longer present and were generated from the accident or during the repair of the vehicle. It is highly important to record all of these faults in your post scan prior to clearing the entire vehicle. It is equally important to put the vehicle through three key cycles to see if any of these codes return. After another full vehicle scan, there were four control modules with active “U” codes in memory for a module not responding on the network. It is not uncommon for other controllers within the network to not report an issue such as this because they may not rely on the missing controller for network data for them to function.
Figure 3
The Gateway Control Module is the main control module that overseas network communications and this was the only module of the four control modules that actually specified the module at fault. The Gateway Control Module stored an active code U104500 that failed the Lane Change Assistance module for not responding on the network. This was odd because there was nothing reported to the instrument cluster to alert the driver of the vehicle at start up. This is very important to know because if there is a control module that is low on the totem pole, the network doesn’t have to report a failure of the module back to the instrument cluster. Therefore, many onboard issues may go unnoticed until a customer comes back with an operating issue. A lot of vehicles will use a tier-rated priority to qualify if the instrument cluster needs to report a failure in the network. So as a quick check of the Lane Change or Side Obstacle System, shops need to view both warning lights on the side-view mirrors at start up. If the LEDs do not light up or both go on and stay on, then there is a problem with the system. At this point, I went ahead and started the vehicle and sure enough the Lane Change icons in both mirrors were inoperative (Figure 4).
Figure 4
This definitely indicated to me that the system was not operating at all. I now instructed the shop to pull the rear bumper so I could examine both rear Lane Change modules and the harness for issues. The left rear module was the master module and controlled the slave module on the right side of the vehicle so I was more concerned with checking the left rear module first.
Figure 5
The shop quickly pulled the bumper assembly off of the vehicle (Figure 5). I visually inspected the connector on the left side and verified the wiring identifications using a diagram from my information system. There were seven wires of which two were power abd ground feed, one LED control to the left side mirror, two CAN lines for the network and two dedicated CAN lines routed to the right Lane Change module to communicate with the left Lane Change module (Figure 6).
Figure 6
Figure 7
I went to remove the connector from the left module and it basically slid off very easily without pressing in the connector lock. The connector was never fully seated and locked in place, and this was the whole problem. I pulled off the connector and closely inspected the lock to make sure it was not damaged. This was a newly installed harness and it was the spring action of the new grommet in the connector that made it hard to click in place (Figure 7).
I reinstalled the connector and started the vehicle and now you could see the indicator on the side view mirror was now working (Figure 8). But I had a new problem. The LED in both side view mirrors were staying on constant without shutting off.
Figure 8
It seemed odd that this vehicle would have a second problem when I had already found the problem. I instructed the shop to leave the bumper off until I scanned the vehicle again to check for further issues. I went back to my scan tool and scanned the entire vehicle again and was able to pull two codes out of the Lane Change control module. The codes stored were 1310721 and 1572868, but there were no code definitions for these codes other than “Unknown Error” (Figure 9). The code number is always stored in the vehicle, but it is the job of the scan tool that provides the definition of it. This fault basically was unidentified because the code library in the tool was not updated yet with the 2019 code list, so it could not properly tag a definition to the code number.
Figure 9
Luckily for me, I have the dealer tool and made the investment to register myself with VW/Audi as an aftermarket dealer tech and I am registered through their security professional database. I placed my VW/Audi ODIS System on the vehicle and pulled codes out of the Lane Change module. These codes were for a control module not programmed and parameterized (Figure 10). These were two separate procedures that had to be done with my dealer level tool. The shop had replaced the left rear Lane Change module with a new one and thought it was just s plug and play module and they were unaware if there were post procedures to be performed on the new module. So I now I had to perform the task of setting up the new control module to finish this vehicle and get it delivered once and for all.
Figure 10
There are many lessons to be learned with this post-syndrome vehicle. There is no guarantee that any vehicle is in perfect order just because there are no lights on the dash. You may want to think twice about post-repair scanning your vehicles for your own investment whether you get paid or not, because there may be many unforeseen issues that may not arise until the vehicle is in the owner’s hands. A lot of control modules on these vehicles today may be plug and play, but it is your duty to find out for sure before the vehicle is released. Some of these replaced modules may just need post procedures performed without programming software once they are changed, and this can be solely done with a scan tool through simple set ups such as calibrations.
Last and most importantly you need to really use your five-sense diagnostics and just make sure things are properly put back in place. Use your eyes, for visual inspections, use your hands to feel things as they slide in place for binding, use your ears to listen for clicks when things lock in place, use your nose to smell for burnt components or fluids leaking, taste is an option at this point. This may help you to prevent unnecessary comebacks down the road. Don’t be that guy plugged into a smartphone with a headset while working on a vehicle because you will lose all of these human sensors at your own disposal. Hope this story has enhanced what you know or didn’t know and possibly hit home with a lot of the readers out there.
We’ve all learned the ABC song, and how to count to 10 as one of our first “organized” instructional classes, even if we didn’t know that’s what we were doing. Now, as a grown up, we’re still learning the same basic golden rules. Be it just a bit differently than our ABCs. As an adult, we follow a flow chart — the basic fundamentals of an electrical circuit — which is like following along with the traditional kindergarten ABC sing-a-long song.
A Ford repair manual covering 1933 to 1947 for the generating and starting system consisted of only 41 pages to cover every detail of the system. 41 pages is just the introduction to today’s complex charging and starting systems.
As with the ABC song, nearly every type of repair scenario starts with the right approach, and the right starting point can make all the difference. If you start on the wrong end or somewhere in the middle, it’s like trying do the ABC sing-a-long song backwards. (OK, go ahead, try it.) It isn't so easy, huh? In this article we’re going to go thru the ABCs of basic electrical diagnostics from easy to a somewhat complex electrical circuit diagnosis.
Early systems
Throughout the history of the automobile, electricity has been a part of its makeup. For a time, 6-volt systems were the norm. Then in 1955, the 12-volt systems became the standard. Positive grounded vehicles were popular for a while due to the fact of the woven fabric covered wire, which had the tendency to absorb moisture. The positive ground reduced the galvanic effect and corrosion that was common on the negative grounded vehicles of that era. Then during WWII, a plastic-coated wire (PVC) was developed which greatly improved the wire quality and integrity tremendously, and the galvanic problems with the copper wires was nearly completely eliminated. This led to the standardization of the negative grounded vehicle.
Computer systems
Now with computer systems and high-tech components, the complexity of the electrical systems in today’s cars have certainly increased. But, the basic principles of electricity haven’t changed at all. Voltage, amperage and resistance are still the three main concerns. However, the critical nature of each have been greatly increased and are by far more susceptible to environmental issues and circuit condition than ever before.
Simple circuit diagnosis – beginners only
Let’s use a simple bulb, two wires and a voltage source as an example. Voltage runs from the battery through the bulb filament and back to the negative terminal lead, completing the electrical path. Thus, making an electrical circuit in its simplest form. Now let’s look at what would happen if we took the negative lead off of the battery terminal. Of course, as you would expect, the bulb goes out because current flow has ceased. But what’s happening to the positive voltage? Has it gone back to the battery and will decide at a later time to flow down the wire? No, not hardly.
A voltage drop can be as little as a loose connection at the battery. Examine the battery clamp connections carefully. Just because the post is secure doesn’t mean the post terminal to negative wire connection is good. Check both.
This is a unique characteristic of electricity. Each polarity will reach out as far as it possibly can to find its opposite polarity. (Talk about opposite attraction). The disconnected lead is nothing more than an extension of the battery positive terminal. (OK, technically there is a touch of resistance added by way of the bulb filament.) Keep in mind, the positive voltage is still at the end of that wire lead, and if that wire lead happens to find another pathway to ground it won’t hesitate to take it. For the novice technician, when a scattering of electrical spark should appear it is usually followed by the complementary convulsive reaction to the sparking wire.
Open (incomplete) circuit issues
One common occurrence is the open circuit problem. An open is exactly what was used in the previous example. In other words, an incomplete path of electrical flow. In most circuits, a loss on the positive side (such as a blown fuse) basically brings the entire circuit to complete halt. (We’ll cover a blown fuse a bit later.) But, on a few occasions, you’ll run across the dreaded “feedback” affect after the original positive signal has been compromised and another leg of the same circuit becomes the voltage source for the remainder of the circuit.
Not in every case, and not that every manufacturer labels the fuse box the same way. But, it’s still a good idea to check the fuse box lid against the wiring diagram and make sure you’re on the right fuse.
A typical issue would be a digital display picking up a stray or weak voltage from another component or as in the case of some mid-80’s Chevy Blazers which had two sources for constant voltage for the dome light and cigarette lighter positive signal, if one leg of the positive circuit would blow the other would bleed current over to its companion fuse, but… only when the doors were all closed. If you’d open the door, the dome light would go off, but close all the doors not only would the light stay on, but you couldn’t shut it off. The only way I found the open fuse was to test the fuses with all the doors closed. (Thankfully, that was back in the day when I was quite a bit more flexible.) With the driver’s door open, and using a test light across the access points of the ATC fuse, all the fuses would check good. (The contact points had voltage on both sides because of the feedback. One side would be the source voltage while the other was the feedback.)
However, if the connection point of failure (the open) is on the ground side it can be an entirely different story. Since the negative is generally a common attachment point for more than one system, it’s likely that you’ll have some other circuit or some unlucky negative signal source becoming the surrogate ground even if it doesn’t want to be. This is commonly referred to as a voltage drop (another later discussion).
When checking these circuits, keep in mind, if your measuring tool, i.e. multi-meter, test light etc. is connected to a known good ground and you touch the unconnected ground lead you will see current flow. OK, maybe a bit lower voltage (or a dim test light bulb) but you will see something. Because you’re “after” the load has been applied to the circuit. (A probe that will show continuity at the same time as the current/voltage is a better choice for this test. But practice using one of these tools before attempting it on an unknown circuit. Accidentally inducing a voltage or even a ground signal in the wrong part of a circuit such as a computer lead can be hazardous to your pocket book.)
Voltage levels vary depending on what system you are working on. High voltage leads are orange (or Blue) to indicate their potential energy levels.
Keeping in mind that no matter if it’s a 5-volt circuit or a 12-volt battery supply lead, a loose or disconnected ground lead has the same potential to cause chaos in the systems. For example, if you’re working on an instrument cluster problem where all the gauges are all reading off (or not at all). The most common issues would likely be the instrument cluster main ground. Chevy S10 pickups through the 90’s had the main instrument cluster ground attached with the same bolt that held the parking brake release lever in place. So, after a few years of releasing the parking brake the bolt would work loose.
The stories a customer would tell you about how they were driving at night and when they’d hit a bump there was this horrific electrical zap by their left knee was more than a little entertaining to say the least. Of course, as an afterthought, they would mention: “And then all the gauges starting working again, even my dash lights!” (Not knowing the zap and the gauge problem were one in the same.)
Connections like these are not designed to be taken off over and over again. Each time they are disturb some degradation to the quality of the connection may occur. Use the PID’s and scanner information first to verify a problem before probing leads or removing connections.
Now, let’s take that same scenario but incorporate a computer or module with various points for the electrical signals to follow. Then create an incomplete path for all of these polarity conscious energy sources and what do you think will happen? Comparing this to our simply bulb circuit, or the electric light show from one of those old S10’s and the results are quite different. Now there’s a better chance of having a service code lead you in the direction of the repair rather than a zap from a loose connection.
Electrical diagnostics has sure changed from when I first started in this business. Back then, a simple test light and a DVOM was about all a guy needed to perform nearly every functional test that was out there. That’s not the case anymore. In fact, a test light can be as misleading as some of your customer’s explanations of their vehicle’s problems. Today, it’s a much more detail-oriented endeavor.
However, the basic electrical formulas and fundamental principles remain the same. (You know, those ABC’s) Not that good connections, and a constant supply voltage wasn’t a concern back on those early 50’s 6-volt systems, it’s just a whole lot more critical in today’s micro circuit-computer controlled contraptions.
Loose connections a few decades ago might bring a customer in with a blinking headlight, or the ever popular “it only works when it wants to” syndrome. Oh, how times have changed.
Shorted (Grounded) circuit issues
The fuse box is a good source of information, because we already know that a blown fuse has to be caused by a short to ground before the load.
Here we are at a blown fuse. Yep, back at the fuse box. The common check points for any electrical circuit, and for good reasons, too. Grounded, or as they are sometimes called, short circuits, are just as the name implies. The voltage supply has found a shorter path to follow than what it was designed for. Generally, in today’s electrical systems the positive side of the circuit is fused. In our example circuit, the fuse would be placed between the positive battery source and the bulb (which can be stated as the work that the circuit is performing). But, the big factor is where in the circuit has it be shorted to affect the fuse? The easiest way to remember this is to ask yourself, “Where is the work at?” The work, in this case, is our bulb itself. So, in order to be a shorted circuit (a positive signal going to ground) we have to introduce a negative potential somewhere between the fuse and the work (the bulb). Not between our voltage source and the fuse, or on the opposite side of the work either. The short has to be between the fuse and the load for any chance of the fuse to disrupt the flow. In other words, every fuse in a car can only blow because something prior to the work has caused the fuse to reach its maximum amperage load.
Just to be clear, there are reasons for a fuse to blow other than a grounded positive signal. I’ve seen voltage differences cause an issue. Such as 15 amps getting sent back down a 10-amp power lead. Not as common, but it does occasionally happen, or as in the next section, a loose connection. Or the work is internally shorted.
Loose connections and heat issues
Loose connections are a form of voltage drop, voltage loss and voltage spikes. Something else to keep in mind when it comes to loose connections, as the connection starts to loosen the current draw can increase as the temperature starts to increase. This heat and can lead to the eventual failure of the connection. If you ever looked at a blower motor on a scope, and recorded what the current does when it is first turned on, you would see a huge current spike or ramp-up at the initial startup. This is quite normal for any electrical motor, (not as prevalent with brushless motors these days) this current ramp only last for a quick burst of energy, but if it remained high longer than designed it could certainly be another reason for a fuse to blow.
Too many times in the past, that I’ve had to go back into a fuel pump replacement job performed by another shop that failed to take a closer look at the melted connectors. Note to self: Check both ends of the connector. Not just the end that’s easy to see. Chances are the other end is the culprit, you know, the one that’s harder to get to and everyone else ignores.
Simple tests – not so simple anymore
Not too many years ago a suspected fuel pump problem or a faulty starter motor could be quickly isolated with a couple of smacks of your trusty shop hammer. However, with today’s brushless fuel pumps and their PWM operation that trick isn’t as effective or for that matter recommended. The older brush type motors had the habit of just conking out after a short trip to the store, or just give up going down the road. A quick rap on the tank could jar the motor brushes just enough to get it going long to drive into the service bay. These new brushless motors don’t exactly conk out, they’re more likely to slowly drop their fuel delivery volume until they just stop completely.
Every customer has a story about their car and its problems. Do yourself a favor and learn to listen not only to the story but the incidental parts of the story that will help you in determining a course of action in the repair process.
But there are similarities between the two types of fuel pump systems. They both have an electrical connection that needs to be checked for melted or expanded connectors. In both types of fuel pump systems (as the pump starts to fail) the current draw will increase. Now, of course, with the PWM type, they’re pretty smart. They’ll set codes to inform you of the situation before it gets out of hand, but that doesn’t mean ignore checking the connector itself. Now, it’s a much better idea to check the STFT and LTFT and see if the percentages are staying close to 0 or at least not above about 5 percent positive trim. But, for the most part the current draw is the main factor that causes the service code to set which informs you of the possible fuel pump efficiency dropping.
Voltage drops
I can’t remember ever using the term voltage drop 20 years ago. If somebody came in with a headlamp with the typical yellow glow, we just called it low voltage or blamed it on a loose connection. Now, that’s commonly called a voltage drop. Today, the loss of one volt on a 5-volt circuit can be as detrimental as a completely open or grounded circuit. In fact, a loss of more than 50 milliamps on a grounded circuit is enough to cause all kinds of havoc. So the thought of a voltage drop is a dead serious issue these days.
I could shorten this whole thing down to a statement that a voltage drop is more or less a loose connection. True, but not always a correct answer. Take a look at some of the new fuel pump systems, for example. A lot of these new fuel pumps don’t run at 100 percent voltage input, but at a 50 percent duty cycle or even less. Running at a duty cycle means that the pump pressure and fuel volume can be controlled by varying on and off time of the fuel pump. However, with some of these other new systems, it’s not a duty cycle at all but a controlled voltage/current reduction from a PCM or fuel control module.
A voltage reduction basically makes the fuel pump run at a slower rpm when the fuel volume and pressure requests are low. Basically, it’s a forced voltage drop (usually around 9 volts) by way of the FPCM (fuel pump control module). So now, (for all you voltage checkers out there), if you checked a fuel pump and saw only 9 volts it may not necessarily mean you’ve got a voltage drop issue. It might actually be in perfect working order. Check the manufacturer’s info for the method they’re using for the fuel system you’re checking before condemning it.
The ABCs of electrical diagnostics – are as simple as 1-2-3.
But, let’s get back to voltage drops, the real ones. Yes, a voltage drop is usually found at a ground connection(s), but is just as easily on a positive connection too. Usually at a factory connection or spliced joint. I’ve found factory multi-crimped joints fail that produced a lower voltage on one wire and not on the other leads in the same multi-crimped joint or junction. Even though the term voltage drop is generically used to describe a lower than designed value on a circuit, the same thing can be said about a resistance value dropping or more to the point… increasing its resistance than the designed value.
Hi and Lo CAN quick checks
This is very apparent when you’re working on a high or low CAN lead. Many times the test procedure will say to disconnect the suspected component and recheck the signal. Even though the test is accurate the results may not be, or as in some cases, it will leave you with an assumed correct answer, such as a CAN line that has an extremely high resistance value (60 ohms per terminating resistor – 2 terminating resistors in parallel – 120 ohms in total is the norm). But after disconnecting a component such as the IC or perhaps the PCM your values are all over the place. You could make the assumption the component must be at fault, only to find after replacing the module, nothing has changed.
It’s another case of skipping over some of those boring steps in the middle of the diagnostic procedures and blindly go to the end of the diagnostic tree looking for a quick fix. Now you’re jumping to conclusions without testing for any of the possible causes as closely as possible.
So you head back to that section of the diagnostic tree that said to ohm check each lead, wiggle test each lead, and verify continuity. That’s when you notice any wiggle of the connector the resistance value changed. The solution, find the bad spot, which in this case it was a faulty factory crimped joint where several leads joined together.
Less than 5 ohms per line is considered good to go, but don’t forget to wiggle the harnesses and connections to be sure you’ve covered all the possibilities. Anytime you see a junction or wire connection in regards to a sensitive circuit, you should pay close attention to the procedures to avoid changing good parts for good parts. In other words, don’t jump from one end to the other without checking the middle — do your ABCs. (Another quick tip is to use your thermal gun (temp gun) at these multi-connections. Look for a temperature rise at the connectors.)
How important are the tools of the trade?
Let’s face it, not having the right tool always makes the job that much harder. There are the factory scanners that can cover every aspect of their manufactured models and several outstanding aftermarket scanners that can do some extraordinary and complex issues. A good multimeter (I prefer one with a min/max feature) and of course a good scope. A good two-channel is a great place to start, but it won’t be long before you’ll want a four or six channel.
Having the right tool but not knowing how to use it can be just as disheartening. Too many times I’ve seen guys shy away from repairs because they are intimidated by a scanner. There are classes everywhere that can help you learn how to use your tools more efficiently. Car repair has evolved into literally a college level job and has left the knuckle busting socket jockeys down on the lube rack. Let’s face it, it’s more geek than grease these days.
You do have one advantage today that wasn’t as available back in my younger years — the internet. With one search you can find out a lot about automotive repair and the tools of the trade. But, that’s a whole other story.
The 16th Annual TST Tech Training Big Event is fast approaching next month, and features training opportunities from industry experts, and expo and chances to win great tools.
Set for Saturday, March 30 at Westchester Marriott in Tarrytown, NY, the Big Event will offer a keynote speaker, three training seminars, a hot breakfast, lunch and snacks through the day.
Be part of the largest electronic handout automotive seminar in the country. Your registration includes a free android tablet loaded with three full-color manuals and a newsletter. “Our goal is to keep our fellow technicians up to date with the latest technology,” said G. Jerry Truglia, TST founder. With Vin Waterhouse of the Waterhouse Group presenting the keynote, below are the training sessions:
TOPIC 1: Kris Lewis, ATG, will present “Direct Injection & Systems Diagnostics.” Gasoline Direct Injection (GDI) is simple in design, but difficult to diagnose. This is why ATG has adapted a “high-level indicator” approach for ruling out possible causes before parts come off. This seminar was built by analyzing actual diagnostic struggles and documenting the shortest diagnostic paths for these systems. Because of this practical approach, you won’t be buried in useless engineering detail – only useful facts that you can measure and that will help guide your diagnostic path.
Lewis brings a unique combination of experience to teaching, including “almost everything.” In addition to decades in a shop focusing on drivability and electrical, he worked with an automotive radio program and mentored many technicians through in-shop training before transitioning into local training and a hotline service in the mid-2000s. In 2011, Lewis joined The Automotive Training Group as a part time trainer. Since then he has traveled the US and Canada delivering ATG training seminars, focusing on practical strategies that he feels are best learned through great interaction with the audience. Lewis is the of Director of Training since 2016 and is a ASE Master L1 A9.
TOPIC 2: John Anello, Auto Tech on Wheels, will present “Advanced Driver-Assistance Systems (ADAS).” This seminar will familiarize you with information on current and future vehicles. System information and a high energy presentation with a detailed case study.
Anello owns "Auto Tech On Wheels" his passion for automotive vehicles has driven him to work on cars for close to 40 years. Anello’s business provides repair garages with on-site diagnostic support for problem vehicles in their shop without having to tow the vehicle to a dealership. In the last 24 years my business has grown to support 1200 plus repair shops, 400 body shops and 50 transmission shops. He is an ASE Master L1.
Topic 3: John Thorton, Autotrain, Inc., will present "In Cylinder Pressure Transducer Diagnostics." Today, in-cylinder pressure transducers are changing how technicians evaluate the mechanical condition of an engine. Thorton will discuss how to interpret cranking and running compression patterns captured by an in-cylinder pressure transducer. Both good and bad will analyzed. Exhaust path restrictions, intake path restrictions, cam timing issues, leaking valves, broken valve springs and much more.
Thornton operates a mobile diagnostic business in the Chicagoland area. Thorton assists his repair shop customers with both engine and transmission drivability concerns, module programming, BUS communication issues, and electrical diagnosis. Thorton has over 30 years of diagnostic experience and is an ASE certified Master Technician with L1 certification.
Attendees will also have the chance to win some great tools, thanks to event sponsors. Last year, the event gave away more than $50,000 in tools and featured more than 30 vendors.
Register before Feb. 24 and save. For TST members, the cost is $125; non-TST members pay $175. After Feb. 24, the cost goes up to $150 for TST members and $200 for non-TST members. Registration closes on March 18. Sign up online at www.TSTseminars.org or make checks payable to TST at:
Throw away your old tread depth gauge, because a new product has come along which is set to change the way the industry presents itself when it comes to advising customers on the health of their tires.
The TreadReader™ from Atlas Automotive Equipment, is an ingenious handheld scan tool which provides an instant 3D image of the tire, providing vital data such as tread depth and adverse wear. Advisory information like mis-alignment or uneven wear due to under or over-inflation is also displayed, presenting a no-question presentation to the vehicle owner on the condition of their tires, and the recommended resolution whether it is immediate or in the future.
“This product really is a game changer for the tire business,” comments the company’s EVP of Garage Equipment, James Boon.
“There is something about human nature that makes many of us naturally suspicious when someone tells you that you have to spend money! However, the TreadReader presents the customer with a very real appraisal of their tires, in a color-coded and numbered format which is easy to understand, on a report that simply can’t be argued with. It removes any doubt or apprehension in its entirety.”
The unit itself is lightweight, robust (the company claims it has the same characteristics of a well-known brand of hammer drill, and can withstand the volume use of a heavy-handed technician!) and requires just a few seconds to run over all 4 tires for instant upload to a smart phone or tablet via the TreadReader App, which can then be converted into a hard printout or emailable document.
Not a new concept, just one that has been perfected
The concept of having an automated measurement of tires isn’t new, with both drive-over systems and alternative-technology handheld units both available, but James feels that until now nothing has offered the level of superiority of the TreadReader for a price that is accessible to the average tire shop or garage.
“Drive-over units are great, but they are expensive and impractical for the majority of workshops,” continues James.
“Conversely, the only other hand held unit we’ve seen simply cannot compete with the level of technology we have in TreadReader, plus it requires an ongoing subscription service making it very expensive even short-term. In essence, we are offering all the technological supremacy of a drive-over system, in a handheld unit, at a sensible and one-off cost.”
Unlike traditional dip-gauges or the laser systems used in rival products, the TreadReader takes a full width, 50mm circumference section of the tire, monitoring 320,000 points of reference. This ensures that obstacles such as debris or even the tread wear indicator cannot confuse the reading, whereas with a single line scan of a laser you are relying purely on that one tiny sample of the tire.
The ideal partner for wheel alignment
It goes without saying that the TreadReader is a must-have for anybody looking to increase tire sales, but the other automatic uplift resulting from using this product is the ability to sell wheel alignment.
The advisory nature of the report will clearly state where mis-alignment is an issue, and given this information a customer is understandably convinced to prevent any further premature tire wear by having the alignment carried out.
“How else can you demonstrate the need for alignment with such clarity?” adds James.
“Setting the aligner up and putting clamps on the wheels looks contrived, not to mention the time element involved. The obvious visual impact of the 3D rendering, highlighted by a red ‘warning’ and advisory comment, all achieved as a consequence of checking the tread depth, is the fastest, most compelling way to ensure a customer understands they are in need of wheel alignment.”
Although the system is clearly an asset for anybody carrying out alignment regardless of what aligner they have, Atlas actually offer a range of both CCD and 3D aligners, making the perfect package for anybody looking to upgrade or get into the alignment business. On the flagship Atlas Platinum 3D system, the TreadReader can even be integrated into the table of the aligner, making the whole process even more convenient.
Cloud-based service provides new level of analysis
To add even more value to TreadReader, the company has recently introduced the TreadManager Portal, which enables anyone managing remotely, or multi-location operations, infinite opportunity to maximise on the scan tool. By logging into the portal, workshops and Service Managers can view essential data on the number of vehicles scanned, activity by technician, and number of opportunities created for tire and alignment sales.
By maintaining invaluable customer data, TreadManager can even predict tire life-expectancy, allowing opportunities for tire sales long after the customer left the workshop!
Helping customers make the most of TreadReader
TreadReader has already been designed to work with existing eVHC (Electronic Vehicle Health Check Systems) and Tire Management Software existing within a business, ensuring that tread health becomes part of the full-spectrum vehicle health monitoring, and the ability to develop and work with other systems is welcomed by the Atlas team.
“We know we have a product that is simply unrivalled in the market today”, surmises James.
“We can present a fact-based argument to demonstrate that TreadReader is simply superior in terms of price/performance ratio, and we know our customers have seen a very tangible increase in business and credibility as a result of employing the product. Developing the product to work with existing systems is all part of the process we envisage in establishing TreadReader as the industry standard for anybody working with tires.
The new Wilton® Mechanics Pro Vise features an exclusive needle roller thrust bearing design that no other vise employs. What sets the design apart is its ability to deliver maximum clamping force with less operator effort. And unlike other vises, operator’s engagement is minimized when the clamping force is released.
The Mechanics Pro Vise isn’t limited to professional mechanics. Its robust and durable design makes it a reliable shop choice for industrial, manufacturing, construction and oil & gas applications as well. For 78 years, Wilton has been manufacturing vises such as the iconic Tradesman® Bullet Vise, for manufacturing facilities, as well as other industrial installations throughout the U.S.
These are not “me too” vises. Wilton’s Mechanics Pro Vises are available in five jaw sizes from 4-1/2, 5-1/2, 6-1/2, 8 and 10 in. jaw widths. What distinguishes these heavy duty vises is their premium materials, and other structurally sound intrinsic features such as an enclosed spindle, precision machined slide bar, innovative needle roller thrust bearing design, and 360º swivel base. The Wilton vises are backed by the company’s Lifetime Warranty.
Shop environments can get awfully dirty with grease, oil, lubricants and other solvents. They can wreak havoc on the vises internal parts. Wilton’s enclosed spindle vise eliminates the problem, as well as corrosion and provides smooth, consistent operation. This feature extends the life of the vise by protecting internal components. The vises
are factory lubricated and permanently enclosed with lifetime lubrication for trouble-free service and operation.
The stout Mechanics Pro vises are virtually indestructible with a 60,000 psi ductile iron movable jaw and base to handle stress while providing long lasting durability in the most demanding shop conditions.
The vises also feature an anvil with a large surface area for meet striking and forming tasks. The anvil is designed to take blow after blow while forming and shaping materials.
The 360º swivel base has double lockdowns to secure the vise to a shop bench.
The Wilton Mechanics Pro Vises (4-1/2 in., model 845M, $239.99 MSRP); (5-1/2 in., model 855M, $309.99 MSRP); (6-1/2 in., model 865M, $399.99 MSRP); (8 in., model 880M, $599.99 MSRP) and (10 in., model 8100M, $829.99 MSRP) are available through industrial distributors and online retailers. For further assistance, contact Wilton Consumer Relations at 800-274-6848.
Wilton Mechanics Pro Vises – Specifications
Stock No.
Model
No.
Description
Jaw Width (in.)
Jaw Opening (in.)
Throat Depth (in.)
Pipe Jaw Capacity (in.)
Net Weight (lbs.)
28810
845M
Mechanics Pro Vise, 4-1/2
4-1/2
4
3-1/2
1/4 - 3
31
28811
855M
Mechanics Pro Vise, 5-1/2
5-1/2
5
3-5/8
1/4 - 3
37.9
28812
865M
Mechanics Pro Vise, 6-1/2
6-1/2
6
4-3/8
¼ - 4
55.6
28813
880M
Mechanics Pro Vise, 8
8
8-1/2
4-1/2
1/2 - 4
83.1
28814
8100M
Mechanics Pro Vise, 10
10
12
5-1/4
1/2 - 5
115.3
About JPW Industries, Inc.
Headquartered in La Vergne, Tennessee, JPW Industries, Inc.® manufactures and markets a wide range of machinery and equipment under the JET, Powermatic and Wilton brands. In addition to its La Vergne headquarters, the company has operations in Switzerland, Germany, Russia, France, Taiwan, and China. It sells through a vast network of distributor partners worldwide. Visit JET Tools at www.jettools.com, Powermatic at www.powermatic.com or Wilton at www.wiltontools.com.
The theme of MACS 2019 Training Event was A/Ccess to mobile A/C technical information but the vibe was enthusiasm and engagement from the over 700 attendees. The MACS 2019 Training Event and Trade Show took place February 21-23 at the Anaheim Marriott in Anaheim, Calif.
MACS exhibit space was sold out hosting 72 exhibitors and 84 booths.
“This year’s attendees were particularly engaged in and enthusiastic about our training classes and we are grateful for all the presenters, exhibitors and sponsors who participated and supported the MACS event,” said Elvis L. Hoffpauir, MACS president and chief operating officer. “We are also looking forward to our 40th anniversary Training Event in 2020 at the Gaylord Opryland Hotel and Convention Center in Nashville next February 19-22.”
Since 1981, the Mobile Air Conditioning Society (MACS) Worldwide has been the advocate for service and repair owners, distributors, manufacturers and educators making their living in the total vehicle climate and thermal management industry.
MACS Worldwide empowers members to grow their businesses and delivers tangible member benefits through industry advocacy with government regulators and by providing accurate, unbiased training information, training products, training curriculum and money-saving affinity member services. MACS has assisted more than 1-million technicians to comply with the 1990 Clean Air Act requirements for certification in refrigerant recovery and recycling to protect the environment.
To learn more about MACS Worldwide visit our website at www.macsw.org. The MACS 40th anniversary Training Event and Trade Show, A/Ccess will take place February 19-22, 2020 at the Gaylord Opryland Hotel and Convention Center in Nashville, TN. A current calendar of all regional training can be found on the training page of MACS website.
A panel of independent members of the aftermarket trade press chose three new products to be recognized at the MACS 2019 Training Event and Trade Show which was held February 21-23 at the Anaheim Marriott, Anaheim, CA.
Recognized for Best Use of Technology in a new product was the NEO+ by Globus Sistemas Electronicos of Brazil. A Globus news release states that, “After the huge success of the Globus Neo family, Globus Electronics proudly presents the Neo+. OLED graphic display control panel. Featuring dynamic function backlighting, features coming from Fox panel, allows a simple and easy interface. Endless knob with an embedded button makes navigation even more intuitive. Bluetooth and WiFi capable, Neo+ is available in a vertical or horizontal model. Neo2+ and Neo3+ panels leverage all of the flexibility and customization provided by Globus Electronics.” For more information visit globus.com.br
Mahle was honored for creating the Most Service Friendly product with its new Arctic Pro ACX 2280 R-1234yf refrigerant handling system. The company states, “ Mahle ArcticPRO ACX2280, which is designed with a unique, ergonomic service door, offers an intuitive, state of the art user interface, navigated through a beautiful 7” capacitive touchscreen. A built-in LED status indicator light at the top of the unit, which is visible from anywhere in the shop, notifies your technicians of completed service. Wireless communication features ensure automatic, permanent software updates. The integrated refrigerant identifier ensures that the proper refrigerant is being serviced and prevents contamination of the unit and your customer’s A/C system. An optional thermal printer offers the technician and the customer a quick print out of services rendered.” For more information visit mahle-aftermarket.com
The Yellow Jacket® ManTooth Wireless Digital Pressure /Temperature Gauge automotive kit was recognized as the Most Innovative new product. Ritchie engineering states, “The YELLOW JACKET ManTooth™ Wireless Digital Pressure/Temperature Gauge Automotive Kit uses Bluetooth technology and an app to provide service centers and technicians with the ability to perform an accurate vehicle A/C system check in less than three minutes (on average). The Automotive ManTooth Kit utilizes a free downloadable app to calculate and display the system’s actual readings in an easy-to-read format on an iPhone, iPad or Android device. Adding this to your current courtesy inspection or multipoint inspection process on every vehicle that rolls up to your shop is efficient and easy. It provides an exact A/C system health status for your customer and maximizes the opportunity to up-sell additional A/C service.” Find out more at yellowjacket.com
Since 1981, the Mobile Air Conditioning Society (MACS) Worldwide has been the advocate for service and repair owners, distributors, manufacturers and educators making their living in the total vehicle climate and thermal management industry.
MACS Worldwide empowers members to grow their businesses and delivers tangible member benefits through industry advocacy with government regulators and by providing accurate, unbiased training information, training products, training curriculum and money-saving affinity member services. MACS has assisted more than 1-million technicians to comply with the 1990 Clean Air Act requirements for certification in refrigerant recovery and recycling to protect the environment.
To learn more about MACS Worldwide visit our website at www.macsw.org. The MACS 40th anniversary Training Event and Trade Show, A/Ccess will take place February 19-22, 2020 at the Gaylord Opryland Hotel and Convention Center in Nashville, TN. A current calendar of all regional training can be found on the training page of MACS website.
The vehicle at the shop is a 2014 Ford F350. The truck is powered with the 6.7 Powerstroke diesel engine and has an automatic transmission. In the last 250 miles, the engine has run poorly and lacked power. It was taken to a diesel shop, where the shop put an EGR delete kit on and removed the exhaust after treatment. This did not fix the problem. The fuel filters were replaced then replaced again, which did not fix the problem either. With the second set of filters installed, the engine would not start; at that point, it was towed to my shop. The next morning, I went to check for any stored DTCs that might be of interest and found that both of the batteries were dead (5.25 volts).
2014 F350 with 6.7 diesel power. The odometer shows 199,500 miles, and the vehicle uses an automatic transmission.
With the batteries recharged and the scan tool hooked up I found four diagnostic trouble codes that would give a diagnostic direction. All four pointed to either a lack of fuel being supplied to the engine or a leak in the high pressure fuel system. The four DTCs were P0087 (fuel rail pressure too low), P008A (low side fuel pressure too low), P0093 (fuel system large leak) and P2291 (low fuel pressure during cranking).
A scan tool can be used to monitor the fuel rail pressure PID, along with the fuel delivery pressure switch PID (pressure switch in the low fuel supply) to get a direction before the hood is even opened. I selected these two PIDs because they will tell me if the proper amount of fuel is being supplied to the engine and if the CP4 pump is trying to build pressure in the fuel rails.
Please keep in mind, on this engine everything is hard to access except the secondary fuel filter and the air filter. The engine is NOT mechanic friendly, so plan out your next move carefully. The IDS scan tool was used to monitor the fuel rail pressure, engine RPM and fuel delivery pressure switch status and the engine was cranked for a few seconds while recording the data. The only change in data was the engine RPM. At this point, I need to start back at the beginning, the P008A DTC, which is for the low side fuel pressure being too low.
Before we move on, the P008A DTC is stored when the fuel delivery pressure switch doesn’t change from its normally closed state to open when the engine is cranked. The fuel delivery pressure switch opens when the fuel system pressure reaches 365 kPa (53 psi) or above. If the fuel delivery system pressure drops below 365 kPa (53 psi) the switch closes, and if the fuel delivery pressure switch remains closed for more than 60 seconds, the PCM notifies the driver by displaying a low fuel pressure warning in the message center, and an engine derate occurs. The fuel delivery pressure switch is located at the top left of the engine in the fuel injection pump supply tube, forward of the secondary fuel filter (Figure 4). Before you grab your favorite fuel pressure gauge to test the fuel pressure, stop and consider where you are going to hook it up. There is no pressure test port. If you really want to test the pressure, you can remove the fuel delivery pressure switch and screw a gauge into the fitting. This takes time to do, so I will be satisfied with using the scan tool and let it tell me if the pressure is high enough or not.
Before we delve into any testing, stop and consider the hydraulic principle. Basically we are working on a hydraulic system and if a hydraulic system is going to produce any pressure, it first must have a pump that is capable of pumping volume and pressure; it also needs a restriction to push against. I opted to start with the electric pump (fuel conditioning module) and work from there. I unhooked the fuel discharge line from the secondary fuel filter and attached a hose so I could take a fuel sample. I also used my scan tool to turn the fuel pump on and off, although this can be done by just cycling the key. The electric fuel pump will run for 30 seconds each time the key is turned to the "on" position.
On to the first test
In taking the fuel sample I want to test three things; fuel quality, fuel volume and check for any air in the fuel system. In this case, the fuel had lots and lots of air in it and it took about one minute to pump a quart jar full with fuel. The fuel smelled ok and was nice and clean. At this point, the primary fuel system has two strikes against it, low fuel volume and air. Will a new fuel pump get the engine to start? The only way I know to find this out is to install a new frame mounted “fuel conditioning module” and see what happens.
With the new fuel conditioning module mounted to the vehicle, the fuel system was primed and tested. The new pump will pump the quart jar full in about 15 seconds and the fuel has no air in it. With the new electric pump hooked up and cranking the engine, the engine did not start, in fact, the recorded scan data did not change at all from the initial test. At this point, we need to move on to the other three DTCs.
The three DTCs in question are the P0087, P2291 and P0093. Before I start taking parts off this engine, I want to do a little research to see what causes these codes to set.
The P0087 DTC, (Fuel rail pressure too low) sets when “the PCM regulates the fuel rail pressure by controlling the fuel volume control valve and fuel pressure control valve. This DTC sets when the PCM is no longer capable of maintaining the fuel pressure”. In a nutshell, it sets when the fuel volume control valve has been opened as far as it can open and the required system pressure cannot be maintained.
DTC P2291 will set when “the PCM monitors the fuel rail pressure (FRP) during the engine cranking. This DTC sets when the FRP does not increase to the calibrated threshold while the engine is cranked”. This is a symptom DTC, which is caused by something else.
DTC P0093 (Fuel system large leak) is the place to start. “This DTC sets when the requested fuel volume control value exceeds a calibrated threshold indicating a large fuel system leak.”
With this information, I can see the low fuel pressure problem is not caused by the electric pump not being up to its task, but because there is an internal leak in the high pressure system. With this leak, the electric pump has nothing to push against, thus no low fuel pressure in the CP4 pump can be built.
Where is the fuel pressure regulator?
The question at hand is “where is the restriction to the fuel flow located in this injection system?” In this case, this restriction is missing. In all fuel systems I have ever worked on, there is some sort of a fuel pressure regulator or fuel restrictor in all fuel injection systems. Let me start out with a schematic of the fuel system pressure and return circuits. Figure 1 shows the low pressure fuel in Red and the return fuel in Green. The schematic shows there are only two places for the low pressure fuel to return to the fuel tank - either through the CP4 pump or through the fuel pressure regulator valve that is housed in the rear of the right hand fuel rail.
Figure 1 - Schematic of the basic fuel system. Highlighted in red is the low pressure fuel supply and in green is the fuel return. There are only two places the fuel can be dumped back to the tank, either through the CP4 high pressure fuel pump, or the fuel pressure control valve that is located in the rear of the left fuel rail.
By doing a little research about the CP4 pump, I found the restriction. The fuel pressure regulator is called an “overflow valve”. This valve is housed in the back side of the CP4 pump, as seen in figure 2. I have circled the overflow valve in Red. Knowing this, the diagnostic process can be simplified. Figure 3 shows the valve with it removed from its bore. The valve is nothing more than a spring loaded pressure relief valve. This valve regulates the low pressure fuel to 55 PSI.
Figure 2 - This pump is from a 2.0L VW, the only difference between the VW & the 6.7 Ford is, the Ford pump uses two pump pistons, and the VW only uses one. Photo shows the “overflow valve” circled in red
Figure 3 - The overflow valve is removed from the CP4 pump. This valve is nothing more than a spring loaded pressure relief valve. Notice the screen on the end of the valve. This screen will catch metal trash if anything starts to come apart inside of the CP4 pump
On this engine, there is no access to the CP4 pump without removing most of the air intake system. The only easy access to the fuel return is on the left side of the engine (Figure 4) where the fuel return line is attached. The fuel return hose can be removed, a short piece of hose attached to the exposed nipple which will allow you to catch the fuel in a container. Now turn on the electric fuel pump and see how much fuel flows from the CP4 pump. In this case, a large amount of fuel flowed from the CP4 pump. I found if I put a restriction in my fuel hose, I could raise the low side fuel pressure to the 55 PSI that was required to open the contacts on the fuel delivery pressure switch, but the engine would not start.
Figure 4 - Here you can see the fuel filter, the fuel return line and the fuel delivery pressure switch. These are about the only things that are easy to access on this engine. The fuel return line can be removed easily and a ½” hose slipped on the nipple. That will allow you to test the fuel return flow.
Getting closer!
At this point, the fuel pressure issue has been found, the system has a huge internal leak and the next step is to verify the integrity of the CP4 pump. To gain access to the CP4 pump, several of the air intake pieces must be removed. Once they are removed you will see the FVCV (fuel volume control valve) mounted on top of the CP4 pump. This valve is held to the pump by two screws. Remove those screws and wiggle the FVCV out of its bore and take a look at the screen. If perchance you see something like is seen in Figure 5, your problem analysis is finished, since the whole fuel system will be infiltrated with metal trash and the complete fuel injection system will need to be replaced. In the case of this F350, the FVCV screen was clean. You can also remove the overflow valve from its bore and inspect it. Inspect the screen that is on the end of the valve for trash and anything that might be out of order. There are two more places to look for trash, the primary and secondary fuel filters. This fuel system returns its fuel to the fuel conditioning module (frame mounted fuel pump) so most of the metal trash will be collected there, but like I have already mentioned, once metal trash gets into this system, it goes everywhere, the fuel tank, filters, fuel rails and the fuel injectors. Metal trash is the death wish on the fuel system. In the case of this truck, the screen on the FVCV was clean and both filters had been replaced in an attempt to get the engine to run again, so cutting them apart did not find any trash. I do not see any evidence of metal trash in this system, so I am good with not having to replace any of the injectors.
Figure 5 - The fuel volume control valve is removed from the CP4 pump. If you see any trash like this on the screen, the whole fuel system will need to be replaced, which includes washing out the fuel tank.
With the problems I have found so far, I came to the conclusion this truck needed to have the CP4 pump replaced. A rebuilt CP4 pump was fit on the engine, and the engine started on the first try. Test driving the vehicle, I found it had good power and ran as it should, the problem is fixed and its time to collect my money and move on to the next Ford Powerstroke problem. I did not take this CP4 pump apart, but I would imagine there has been a piece of steel break loose inside the pump and get lodged in the overflow valve, which is holding the valve open and letting the fuel bypass back to the fuel tank.
How important is fuel quality
Thinking back many years to the mid ’50s, the first diesel powered machine I can remember being around was a Caterpillar D6. The fuel cap was a large aluminum screw on cap, and molded into the cap were the words “buy clean fuel, keep it clean.” When working with diesel fuel systems, these words are words to live by. Any dirt or water getting into the fuel can and will work its way into the pumps and injectors and will just plain ruin the fuel system.
Diesel fuel had four jobs in the engine. It is used to lubricate the internals of the fuel injection system; it also is used to seal the inside of the injection system as well as cool the injection system. Last but not least it is used to power the engine. Don’t diminish the importance of the diesel fuel that is running through the fuel injection system.
Man-made problems can take many forms. Sometimes a man-made issue is caused by an honest mistake. Other times it can be caused by a faulty part. In some circumstances the fault could be the result of a substandard repair that was made quite some time ago. Some may even argue that every issue with a vehicle is a man-made issue since man made the vehicle in the first place…I digress. Regardless, stepping back for a moment and re-assessing the situation is in order. Each situation will be different. These issues can be broken down into a few different categories. Let us explore them individually.
Story #1: Insanity
We need to remember the cliché definition of insanity: repeating the same action over and over again and expecting a different result each time. An example of this would be: “I replaced the Mass Airflow sensor three times, so maybe the fourth MAF sensor will fix the problem.” I experienced this exact issue on a Mazda. A shop was on MAF sensor number four in an attempt to resolve a low power issue. The fault was actually a restricted catalytic converter. Maybe, in this case, they should have stepped back and reassessed the situation. What is the likelihood of getting four faulty parts in a row? I agree that faulty “new” parts could be an issue. Technically this was not a man-made issue initially, but needs to be recognized none the less.
Moral of the “Insanity” story: If a part does not fix the issue initially, step back and review your diagnostics. Accept the fact that you are human and you may have made an error. Learn from the mistakes and diagnose the next one more efficiently.
Story #2: Common sense
I was called to a shop to program a Jeep engine control module. I consulted with the shop prior to my visit and confirmed that a used JTEC (Jeep Truck Engine Controller) could be made to work on this particular vehicle. When I arrived, the technician informed me that they had replaced the valve body in the transmission due to a solenoid DTC. The vehicle started and drove into the shop before the repair and now the vehicle does not crank. The TCM (Transmission Control Module) no longer communicates with the scan tool but all other modules, including the JTEC, do continue to communicate. The technician “followed the charts” and determined that the JTEC needed to be replaced. Also, poking my head under the vehicle, I noted the transmission pan was not installed.
Does this scenario raise some questions? The vehicle cranked and started before the repair so what changed? The scan tool communicated with the TCM prior to the repair but now does not. What changed? The kicker: the TCM does not communicate but the JTEC does… so let’s replace the JTEC? I am not quite sure why the technician came to such a conclusion.
The diagnosis was actually quite easy. Maybe it was because I showed up with “a fresh set of eyes.” Maybe it was just common sense. My approach was to attack the “new” no crank issue. Connecting a scan tool confirmed that the TCM did not communicate. The JTEC did communicate and the gear selector PID indicated DRIVE. It is a pretty safe bet that this is why the JTEC is not commanding engine cranking. Since the valve body had just been replaced, I chose to disconnect the connector at the transmission valve body. Lo and behold, I regained communication with the TCM. The customer was informed that either the valve body had an electrical issue or improper installation had occurred. The valve body was replaced with another unit and the issue was resolved.
Here are a few common sense questions we should ask ourselves: Why would replacing a valve body cause a JTEC to fail? Why would replacing a JTEC solve a communication issue with a TCM? Why did the vehicle start and drive into the shop and now it does not start after a transmission repair? Most importantly, why did this technician go down the proverbial rabbit hole? We have all gone down this path at some point in our careers. In hindsight, I think we can all agree that the heat of the moment clouded our common sense. When confronted with “the hole” step back and gather your thoughts.
Moral of the “Common Sense” story: If things do not make sense STOP. Step back for a moment and reset your thought process to avoid the rabbit hole. If it seems like something does not make sense then it probably doesn’t.
Story #3: Do not be a slacker
Quality repairs do many things: fix the vehicle permanently, please the customer, please the boss, improve shop profitability and more. However, cutting corners on a repair might be sufficient (not acceptable) in the short term yet catastrophic in the long term. Piercing a wire for example could cause corrosion issues in the future. I constantly pierce wires for testing purposes but I always make sure to repair the wire I pierced with some acceptable type of sealant or wiring repair. My point: make a QUALITY repair to avoid future issues and come backs.
Figure 1 - Testing ground at pin 4 of the DLC resulted in bright test lamp illumination.
Here is an example of a sub-standard repair that caused the customer to spend lots of time and money when they should not have had to. In addition, a logical diagnostic process led to an accurate diagnosis in the end. The vehicle in question is a 2001 Dodge Ram 1500 with a 5.9 liter engine. The vehicle would crank and not start. Also, a “no bus” message was displayed in the odometer. The customer replaced the engine control module with a used unit and was requesting programming.
Figure 2 - Pin 5 of the DLC has a voltage drop that can be seen due to the lack of test lamp intensity.
Initial inspection confirmed that the MIL did illuminate and the vehicle was cranking and not starting. A scan tool was connected and communication was attempted. Ironically, the engine started when cranked. Disconnecting the scan tool caused the vehicle to stall. Reconnecting the scan tool allowed the vehicle to start again and disconnecting it yielded the same stalling result.
Figure 3 - A jumper wire was used to provide a good ground to pin 5 of the DLC.
Knowing that there is one power pin, located in cavity 16 of the DLC, and two ground pins, located in cavities 4 and 5, got me to thinking: could the scan tool be providing a missing ground between pins 4 and 5? A DLC breakout box was then connected in order to test the ground circuits. First, pin 4 was tested with a test lamp (Figure 1) and it illuminated brightly. Next, pin 5 was checked (Figure 2) and the same result was not achieved. The test lamp did illuminate but with much less intensity. The next step was to confirm our suspicion of the scan tool providing a ground for the vehicle. A jumper wire was installed between pins 4 and 5 (Figure 3). As suspected the truck started and ran. Disconnecting the jumper, no surprise, again resulted in a stalling situation. Time to trace some wiring diagrams.
Figure 4 - Touching the ground wire caused the substandard repair to fall apart.
Following the wiring diagrams backwards from the DLC leads to ground G105. This ground is shared by the DLC, PCM and many other components. Could this ground be the cause of all of our issues? Further research leads us to the ground location on the left front of the engine. It was obvious, when inspecting the ground, that a repair had been made. Touching the wire caused the replacement connector end and the ground wire to separate (Figure 4).
In this case, a shoddy wiring repair may have worked initially but failed further down the road. In Figure5 it looks like the connector end that was chosen for the previous repair was too small for the copper wiring involved. Instead of choosing the appropriate connecter the small connector was “modified” to fit. I’m not sure, but it looks like no solder or crimping was used and the plastic heat shrink of the replacement connecter was relied on to hold the wire in place and maintain good electrical contact? This fault, and subsequent unnecessary PCM replacement, could have been easily avoided by performing a professional quality repair the first time around.
Figure 5 - This connecter was not even crimped or soldered together.
Moral of the “Don’t Be a Slacker” story: Do not cut corners on a repair. We are professionals so let us make sure our repairs reflect professional quality. Otherwise we risk inventing new problems later on down the road.
Story #4: Not much you can do about it
The toughest man-made issues to diagnose are the odd ones that occur after a part is replaced and a new issue arises. Although this may sound similar to the valve body story from earlier in this article. The no crank issue from that story could have probably been easily found if the appropriate OE charts had been followed. What I am referring to now are issues where the OE charts would leave you hanging. Or even worse: “install a known good module and retest.”
These types of issues often require a creative way, using our knowledge and tools available, to design a test to prove what we want to know. For this example we will use a Durango… sorry it is another Chrysler product.
The subject vehicle is a 2002 Dodge Durango with a 4.7 liter engine. The vehicle was purchased at auction and, upon arrival at the shop, was determined to have a bad engine. A salvage yard engine was installed. The vehicle started and ran but, I was told, had mechanical issues. A second salvage yard engine was installed and now the vehicle cranks and does not start. The technician installed a spark tester and observed strong spark from the ignition coils. The engine did try to “fire” occasionally but never really started. It was probably a safe bet that fuel is getting to the engine due to the occasional firing, but to be sure the technician installed a fuel pressure gage and the results were within specification. As a last ditch effort the technician used starting fluid to no avail. At this point I got the call.
My first step was to plug in a scan tool. Of course, the auction vehicle had a dead battery and, as a result, no DTC’s were stored. A charged battery was installed and testing resumed. Cranking the engine did show engine RPM on the data list and no other data PID’s appeared to be out of whack. Given the situation I had a few questions: What was the mechanical condition of the used engine? We had some spark, but was it occurring at the appropriate time?
Figure 6 - A relative compression test shows 2 ignition firing events and then about 8 crankshaft revolutions before firing again.
The next step was to perform a relative compression test to determine if the engine had equal compression across all cylinders and to get a rough idea of spark timing. A scope capture was obtained (Figure 6) and something definitely did not look right.
If each current peak in the capture resembles a compression stroke, then why are there around 30 compression events on this 8-cylinder engine between firing events? The engine appears to have some mechanical integrity so ignition timing will be investigated next. Ignition timing, on most modern vehicles, is based off of the crankshaft position sensor signal. The decision is made to scope the crankshaft and camshaft sensors and move forward from there.
Consulting wiring diagrams in service information revealed that this vehicle had two possible engine control diagrams. One is for a 4.7 liter engine equipped with a JTEC engine controller and the other is for a 4.7 liter engine with an NGC (Next Generation Controller.) The two options were easy to distinguish from one another because a JTEC has three connectors while an NGC sports four connectors. This Durango was equipped with a JTEC and the appropriate scope connections were made. A scope capture (Figure 7) was obtained and compared to a known good capture.
Figure 7 - The capture obtained from the Durango is for an NGC controller not for the JTEC with which it is equipped.
The scope capture that was obtained looked great if the Durango had an NGC. However, this vehicle’s JTEC is expecting a completely different pulse train from both the CKP and CMP. Both the crankshaft and camshaft reluctors were wrong for the vehicle.
This vehicle had the wrong engine installed and needed to be replaced for a third time to resolve the issue. This can be a problem when salvage yard parts are used and is more common than one might think.
Story #5: Not much you can do about it – Part II
This last vehicle was a Mazda 3 that had a used engine installed just like the previous Durango example. Only because it is important for the diagnosis, I would like to point out that this vehicle was in the Chicago Illinois area. The Mazda ran and drove fine after the engine was replaced with the exception of MIL illumination for a P0171 Lean Exhaust Bank 1 DTC.
This vehicle landed in the bay of a second shop when the first shop threw up their hands. The shop consulted with me on the phone and relayed fuel trim data to me. The fuel trim numbers were equally positive under all conditions which suggests that the existence of too much Ethanol in the tank of this non-flex fuel vehicle was a strong possibility. An Ethanol test was performed and the fuel was well under the ten percent mark.
When I visited the shop, and connected the Mazda IDS, I noticed on the vehicle ID screen that the vehicle conformed to California emissions requirements. What do you think the chance of finding a California emissions engine in a Chicago area salvage yard is? Further research confirmed that the fuel injectors for a California emissions application had a higher flow rate than the non-California counterpart. If the injectors now have a lower flow rate than the injectors the PCM thinks it is driving the engine will indeed run lean. A set of California fuel injectors was ordered, installed and the fuel trim numbers came right back in line.
Moral of the “Not Much You Can Do About It” stories: Salvage yard parts are not always a bad choice, but occasionally an unforeseen issue can blindside you. When this happens, a creative approach to diagnostics, observation of even the smallest details and additional research will help one find the resolution to the issue.
In summary, man-made issues are unavoidable. Weather it is your fault or not, the vehicle still needs to be fixed. Professional repair techniques will help avoid some of these issues. Common sense diagnostics will help avoid some of the rabbit holes. And observation, research and creative thinking should help resolve the rest.
Every now and then, my wife and I look forward to loading up the little RV we own and getting a weekend away to decompress. The last such weekend was near the end of January. While my wife was finishing up her workday, I filled up our 2013 Ram pickup with fuel and hooked her up to the trailer. In just a few hours, my wife would be home and we'd be on our way.
Now, to put this into some additional perspective, the RV has presented me with some real challenges over the last six months of 2018. I've had to rip out a large part of the flooring to repair water damage caused by miscellaneous leaks and most recently, had to have the rear ramp of this "toy hauler" rebuilt due to water damage to its base. The last time we had a chance to really enjoy it was late last summer. So you can imagine how much the two of us were looking forward to this trip.
My wife gets home and after an hour or so of final prep, it's time to hit the road. I put the key in the ignition and — NOTHING! Only an error message in the instrument panel display that's telling me that I'm using the "wrong key fob." I drove this truck not three hours prior to this!
How can it be the "wrong key fob" when it's the same key I just used three hours ago? That's what your customer is asking themselves.
It didn't take too long to figure out that we were going nowhere until the key was replaced and programmed to the truck. I couldn't even put the vehicle in neutral to move it away from the RV. With a little help from my youngest son, we disconnected the Ram's driveshaft and used his Ford F250 to tug it out of the way. And with the help of another youngster I've known since his high school days, we hooked up to a substitute tow vehicle and still made it to our final destination before midnight.
As we drove down the driveway, I could only think to myself, "What if this happened AFTER we got to the campground?"
Understanding your customers' frustrations
I think you know how frustrated I was when the truck failed to start. And you can probably understand how even more frustrated I was when faced with a problem I couldn't fix. My wife sat patiently in the front seat of the Ram as I tried several times to start the truck, only to get the same error message. She offered suggestions similar to what I'm sure any helpful wife would offer their husband when faced with this situation. "Try wiggling the key, honey." "Are you sure you're using the right key?"
After we had settled in at the campground, I had a chance to consider "How would a consumer with no knowledge of this system's function feel in this same situation?" A couple had planned their weekend getaway weeks in advance, made the necessary reservations, packed carefully to make sure nothing needed would be left behind. Anticipation is high and then the balloon bursts as a vehicle failure puts an abrupt end to everything.
It's easy when we sit on the other side of the service counter. "I didn't design it, I didn't build it, and I didn't break it — but I can fix it — for a fee." But to the consumer that is standing there across from us, the failure he's bringing in to you for help represents more than just a minor inconvenience. It means missing that weekend away with his wife, his son's championship game, his daughter's first dance recital. Our society is built on the automobile as a personal conveyance and when something happens to it, our world comes to a sudden halt.
The vehicle failure isn't just an inconvenience. It's a missed trip with your spouse or dance recital with your daughter.
So when your customer, whether he's on the phone or at your counter, is upset and short with you — remember, it's not personal. He's upset because something he's come to depend upon has failed him and he doesn't know what to expect next. Keep a smile on your face and compassion in your heart and help him get that lost moment back.
Avoiding your own frustration
Many of you are probably getting tired of me repeating a common message of mine, but there has never been a time in automotive history where staying up-to-date has been so important. And, in my personal opinion, it has never been easier to do so.
Just this month alone, there are four opportunities to attend live events around the country. By the time you read this, one or two may have been held already, though you could certainly mark the dates on your calendar for next year.
The first March opportunity is one you must attend at least once in your career, and that's the VISION HiTech Training event and Expo. It is held in Overland Park, Kan., and always has a "Who's Who" list of trainers to choose from. Following VISION is the Automotive Training Expo (ATE), held by ASA Northeast in Seattle and the AVI Training Conference held in Fort Myers, Florida. Both offer excellent training opportunities to techs and shop owners alike. And bringing up the end of March is the TST "Big Event," a unique single-day training event hosted in Tarrytown, New York by the same team that helps me bring you our quarterly webinars.
No matter where you live in the country, there is an event near you.
And if you can't take the time to attend one of these national events, talk to your parts suppliers. Nearly every major aftermarket supplier has increased their training efforts. Federal-Mogul is just one that comes to mind; building new training centers around the country and hosting more localized training opportunities. And they are not alone. NAPA, Standard Motor Products, WORLDPAC, CarQuest and so many others are hiring staff and increasing their training capabilities.
Why? A few reasons, I think. One, more and more of you are "seeing the light" and seeking out these training opportunities. Two, publications like ours are doing more to bring these resources to the attention of you who've looked long and hard for them. Third, it's no longer a matter of "do you want to learn more," it's becoming a matter of "you HAVE to learn more" if you want to stay successful in this business. We simply can't approach our repair processes the same way we have in the past.
Yes, it's not getting any easier to service and repair the products the global OEMs are producing. But rest assured that your team at Motor Age will do all we can to help you rise to the challenge. As our cover of every issue says, "Advancing the automotive service professional since 1899."
I think we have all been in the situation as a shop owner, mechanic, technician, handy man or whatever you like to be called where we are approached by a family member or a close friend because they know one thing. They know you can “fix things.” Ninety-nine percent of the time we are more than willing to lend a hand, or at least I am, and especially in this case. It was my one and only sister who called me. Mind you all three of her brothers are mechanics as well as her dad and we all own shops but it was my turn this time. Either they copped out or I was just the first one who answered her call.
She called to let me know that the front wipers on her 2014 Dodge Grand Caravan with 71,870 miles on the odometer had stopped working and wondered if I could take a look at it for her. She goes on to tell me she already spoke with dad and one of my brothers who both referred her to me. So there, I got my answer as to where I fall on the call list and was voted the best “family mechanic” for the job, apparently.
That day she swung by the shop and explained, or I suppose the better word would be, hoped it was “just a fuse.” Because we all know fuses are cheap! Knowing the problem that seems to follow Chrysler around since the invention of infamous TIPM, I was pretty sure we were not going to find a “bad fuse.”
Figure 1
I pulled up a diagram (Figure 1) and grabbed a scan tool so I could see wiper inputs into the TIPM. After releasing a few fasteners on the cowl so I could gain access to the wiper motor plug I was ready for some testing. Looking back at the diagram it is a relatively simple lay out. One fuse (that was not blown), two relays and some logic to control it all. I wasn’t too concerned at the moment how the input from the wiper switch made it to the TIPM and how many modules it ran through to get there but I could see on scan data that it did make it there. Every selection on the wiper stalk was being displayed in the live data. The next obvious step was seeing if the power was being sent through the relays and up to the wiper motor. I quickly discovered at this point it was not! The wiper on/off relay appeared to be permanently latched to pin 87a which leads straight to a ground. Knowing all of the inputs were good, the testing was good and 100 percent definitive I gave her the bad news.
It's going to cost HOW much?
We can all assume what happened next when I revealed the cost of the new TIPM plus the cost of the 2-day subscription to Tech Authority so we could program and restore vehicle configuration to finish the repair. I think some call it puppy dog eyes, sob story or crying the blues. In either case I saw this as an opportunity to try and repair the failed relay on the board with nothing to lose. Besides, it was my sister, not a “real customer” right? I told her the risk involved and also exposed the fact I have little to no experience with printed circuit board repair. We agreed on the $15 fix and I ordered a new relay (Figure 2).
Figure 2
Figure 3
What did I get myself into!? The TIPM comes out of the vehicle in about five minutes however I was the better part of 45 minutes trying to get it apart to get to the good stuff (Figure 3). The smart phone came in handy during this part as every fuse and relay had to be removed. There were four stacked circuit boards that were pretty resilient and eventually I was able to get down to the green printed circuit board that had the relays soldered to it (Figure 4). The only down side was there were about six relays on the board and I had no idea which one of the 10 pin double relays was at fault.
Figure 4
Figure 5
Not knowing any better way, I decided to energize the control side of each relay and determine which one did not work. I was later told by several people that this was not a good idea and could have caused some damage. Either way, I was quickly able to determine the one at fault (Figure 5).
Figure 6
Now came the fun part. Trying to de-solder the old relay. I bought some fancy magnifying glasses that helped tremendously, I also bought a solder sucker and some solder wick. I failed miserably at both to say the least. 20 minutes into it I started to wonder how much heat and fiddling one of these boards could take (Figure 6). The answer to that question is a lot! At least it was in my case. Trial and error eventually got the old relay removed from the board. I can say I was relieved to see when I took it apart that the contact was clearly fused together (Figure 7). At the same time, I wondered if this whole mess was going to work once it was put back together.
Figure 7
Finally, the EASY part. Soldering the new 10 pin relay in was a breeze. Rest assured snapping all of the plastic bits together is way easier than taking them all apart. It was a little tedious with sausage shaped fingers full of arthritis to do the job but it was very satisfying to see the finished product (Figure 8).
Now for the moment of truth. I installed the TIPM in the vehicle, cleared the codes, pulled up some data, said a little prayer and turned on the ignition. Palms sweating, I flicked on the wipers and they WORKED! High, low and intermittent. I actually did it! I know too many of you it may not sound like a big accomplishment but honestly it felt good to carry out a repair I would have never thought of doing in the shop for a customer. Sell a TIPM? Sure, we do that on a regular basis. Tear one apart and do a repair? No way! As a shop owner I can’t be married to a vehicle for an experimental repair that could quickly go South. On my sister's car, well that is a different story. My dad always called it government work when we had to work on family’s cars. I never really knew what it meant but it sounded good. In this case it has a happy ending. She had her van fixed on the cheap and I looked like a hero. Although truth be told I think I had a little luck on my side that day.
As a side note I posted this repair on my YouTube channel and reaped some of the many benefits of having one and that benefit is community. I received thousands of comments full of tips and tricks for removing soldered pins as well as the correct types of tools that should have been used. In my opinion that was the biggest benefit I received and continually receive from my channel. There are a lot of folks out there from a lot of different corners of the world willing to share their knowledge and expertise on subjects that are way outside of my wheel house.
The scene opens with the camera fading in to reveal some of the characters. There's a young unnamed couple, it's a beautiful day with plenty of sunshine. They are frolicking without a care in the world and appear to be dancing in an open field of flowers with total abandon. There’s a picnic basket, a bottle of wine and two glasses, some homemade snacks and two pairs of shoes on the edge of an unfolded sheet. By the looks of their clothing it must be taking place somewhere around the mid-1960s. The camera fades to dim as the couple runs towards a standing of trees hand-in-hand.
The scene continues on a street which looks like any typical residential neighborhood for the time period, where the newest car seen is a 1968 Ford LTD — and it is being jump-started. The camera pans to one of the other vehicles alongside the road with its hood open. Before the camera can view what's happening in front of that car there is a loud bang! Sparks fly and smoke billows as two young lads jump back screaming. One partially disrobes, taking his T-shirt off to try swat at the flames now erupting from an unseen location. He then uses it to insulate his hand as he grabs one of the jumper cables.
It's clearly apparent that a proper procedure was not followed! The camera fades to dim.
Fast forward. The same unnamed couple, slightly older now, is arguing. A child cries in the background. It’s clearly evident there's trouble in paradise! Past-due bills are scattered on the dining room table. Old newspapers are laying on the living room couch and chair. One of the window blinds is cockeyed and the home appears in total general disarray. The camera fades to dim.
In the next scene appears a student at a desk testing intently. He slams his book shut, hands the teacher his paper and leaves the room. The student is one of the two young men who were attempting to jumpstart that LTD many years ago. In the next scene he is shirtless on his couch with an infant on his knee that is sucking a baby’s bottle while at the same time, a technical service manual that he's reading rests in his lap. Beside him, a half-eaten dinner sits on a plate. He decides it's time to put the baby to sleep, go take a shower and call it a day. His dinner never gets finished. The camera fades to dim.
When the camera fades back in it shows us a current environment. The familiar girl, aged now, crying on the phone. She is hysterically explaining she doesn't “KNOW what happened” to whomever it was that was listening on the other end. The camera pans out to show knocked over furniture, a lamp lying on its side yet still brightly lit and a smoky kitchen stove with a pot on it while unintelligible discussion takes place in the background. There are someone's legs, attached to feet with shiny, new-looking shoes on them, visible beside the kitchen doorway but the body is lying still on the floor. Sirens wail in the background. The woman cries uncontrollably as the sounds of police vehicles gets louder. The camera fades to dim.
In the next scene appears a now well-trained mechanic who is sitting in a 2003 Ford Excursion just across the street from an unkempt yard where two police cars arrive from different directions. He looks up curiously as the police officers rush to the front door of the house, already slightly ajar. His curiosity lasts only so long and he returns his focus to the IDS software displayed on his laptop on the seat next to him. He has a job to do, he mutters to himself, thinking he doesn’t have time to satisfy his curiosity about what may be happening across the street. Thankful, he feels, that he didn’t get involved when he next looks up to see yellow “Crime Scene” police tape being attached to trees surrounding the property he can see through the windshield.
Unfortunately, he gets dragged into the criminal investigation when an observant police officer notices Jaime and comes over to chat. The officer queries the mechanic then stops abruptly after one of Jaime’s answers. It wasn’t something that quite “fit” into the crime scene — and causes the officer to say “well, we didn’t know THAT before now.” Suddenly, the sound of a gunshot interrupts the impromptu interrogation…
When customers are less than truthful
Have you ever been performing diagnostic routines that presented results inconsistent with the customer’s explanations of the events which led up to the failure? Did it make you think you were dropped into some sort of a TV Crime Drama show — the way nothing you were finding wrong with the vehicle was making any sense based on what you were initially told? Sometimes, when further queried, the customer suddenly remembers other, usually vitally important, facts and anecdotal parts of the story which were mysteriously omitted when the diagnosis first began. It can be a frustrating experience, one that’s shared by many of our readers every day!
2003 Ford Excursion
This Excursion, with 186,823 miles and a direct injection — Turbo 6.0L, was just that type of a “job.” Knowing the shop owner, as I have had dealings with him before, I know his communications sometimes require deciphering in order to understand them. This text was no exception. The shop owner’s initial complaint was stated as: “The vehicle was towed here after the batteries went dead overnight, but with anti-theft issues can you remove them." I’m already feeling like I’m in a who-dunnit.
Ford IDS software doesn’t “know” whether a vehicle is fitted with a particular module.
Where you get Ford’s As-Built Data to program a module as it was originally.
Upon arriving at the shop, I found both of the batteries (this is a diesel) were dead. Zero volts; “Oh, just wonderful” I thought. If we are to be able to accurately diagnose ANY type of electrical problem, we MUST have fully charged batteries, ones which pass a load and a conductance test. After I explained this to the shop-owner we agreed he would charge the two batteries in the vehicle and I would return at the end of my day. When I returned, I scanned the vehicle’s network, found a Powertrain Control Module (PCM) without a VIN and a Generic Electronic Module (GEM) not reporting. I asked them to order one and left because it was late in the day. I was going to do some research at home, now that I have some initial tests performed and an IDS Log File with lots of information to which I can refer. They called, the dealer argued about the truck needing a GEM, and claimed the vehicle wasn’t equipped with it. I did some research; IDS said it was "OPTIONAL" as did the Ford Professional Technician’s Society (PTS) website. OK, no problem, I scheduled time to go back the next day.
Aftermarket “Tuners” may write a fictitious VIN when they reprogram a module.
To confirm a PCM is communicating on a network, observe a parameter that’s shared by another module (in this case, the Odometer is stored in the IPC).
Upon arriving the next morning, you guessed it, the batteries were dead again! The shop personnel had neglected to disconnect them prior to leaving for the night before. I had them install some known-good units so that I could perform testing. I focused first on the PCM. I found and removed an “Aftermarket Flash” (using owner's equipment) then reinstalled the original flash using Ford’s As-Built Data. The IDS then found a new update for the PCM, FICM & TCM, so I performed the update to ensure all three were up to date. I was required to perform Passive Anti-Theft System (PATS) functions after programming the modules. I was allowed Parameter Reset, but it would not allow further access to perform Key Erase, etc. It seemed to be locked in some way. It would not allow the starter to crank the engine and codes were set in various modules, which helped influence the PCM’s decision to allow the engine to start. Prior to completing testing for the day, we put the shop owner’s PCM in place of this one and found the engine would crank. He ordered a PCM.
Although not a place frequently thought of for such things, I found on this page the Vehicle Security Module had absolutely NOTHING to do with Anti-Theft system.
The “VIN Write” function can be skipped during the programming process.
A little homework
I went home and researched some more that night. I found some interesting information about the systems used on this vehicle, which were unlike most others I’d worked on in the past. For instance, thinking because I had Vehicle Security Module (VSM) codes, that those Diagnostic Trouble Codes (DTCs) may be influencing the PCM. A replacement VSM was ordered before I found data indicating it is NOT responsible for anti-theft (so I didn't open or install it). How silly of me to assume a Vehicle Security Module might control Anti-Theft functions! Am I right? In this case, the VSM is in charge of exterior lighting, some of the restraint information and other sections of the vehicle that keep its occupants (safe and) secure.
Not the most helpful of information but sometimes these PIDs may assist with a “No-Start” complaint.
I also learned that a first version of Ford’s Vehicle Communication Module (VCM) must be used to access the PATS functions on this vehicle. More diagnostics led me to think the PATS module is causing the no-start, but since it doesn't prevent the starter operation, and a replacement PCM allowed it, I knew the PATS module was simply doing its job. This logic was perplexing.
This routine is a very simple, two-step diagnosis. Well, it’s supposed to be!
A very strange piece of evidence, a recurring DTC P1260 (Engine disabled by PATS), was setting intermittently the whole time while I was diagnosing the vehicle. If it wasn’t present (for instance, when I finished programming the PCM) then the starter would operate. As soon as the key was released, the DTC would set and the starter would not be commanded to operate. In addition, I found the Radio & Windows operated with Key OFF! I traced to this phenomena to a bad Instrument Panel Cluster (IPC), which was improperly causing the Accessory Delay Relay to stay activated. I did not check to see if all of the vehicle amperage draws were gone with the IPC disconnected (and regret now not doing so). Isn’t this “PLOT” thickening? See how the evidence doesn’t really coincide with what the original complaints were?
After PCM programming, PATS functions must be performed before the engine will start.
Once the IPC was installed, a replacement key was obtained for one of the two provided (which was held together with Scotch tape) and programmed, a Ford remanufactured PCM was installed and programmed (an aftermarket unit failed to program to completion) and all the PATS functions had been completed then the starter would crank the engine without a DTC P1260 setting.
We need to look at a wiring diagram to see what is most likely at fault, as was the case when the Power Windows could still be operated when the key was out of the ignition.
However, the engine would not start. In addition, there were now only six “U” codes (Vehicle Communication Network DTCs) setting instead of ten or more found initially — which was contributing to my jumping to the conclusion the GEM was faulty since it would usually be the module in control of such things. There were 29 DTCs found throughout the vehicle’s 11 modules now reporting on the network.
Just the facts, please!
All these clues do not coincide with a “Batteries went dead” complaint. I queried the shop owner one more time, explaining why I was perplexed and asked if he could offer any more information that could help me resolve the seemingly unusually large number of problems indicated. That’s when he said he had spoken to the vehicle owner earlier that day to bring him up to date about what’s been done so far. In his conversation the owner admitted he tried to jump start the vehicle.
This vehicle owner shared a story from a long time ago about how while jump starting “an old Ford” improperly he made the car battery explode! He also shared that this time he thought he was being careful when he did it to his truck but made the same mistake, reversing the polarity of the jumper cables. He knew because of the sparks and heat that formed in the clamp he was still holding, just like they did “way back then!”
It appears the ignition key must have been left in the ON position when the attempted jump starting took place (due to the extensive damage). This last bit of information is what made all the puzzle pieces fall right into place. The feeling of being an unwilling participant in a crime drama soon left me. Thankfully.
In 2015, I wrote an article (“Inside the IDS,” June) and I detailed some of the other tests IDS can do besides pulling codes and looking at data PIDs to enhance your analysis of that Ford that is in your bay. Ford is constantly making changes in the software in their vehicles and adding tests of that software into IDS. They release how-to information on their Motorcraft/PTS website in General Service Bulletins (GSB). In this article I’m going to tell you how to access these bulletins along with some examples of using IDS as these bulletins explain.
Ford publishes three types of service information that isn’t in their Service Manuals. The first is the typical Technical Service Bulletin (TSB) detailing issues that are found in the field and often apply to multiple vehicles. The next Special Service Messages (SSM), are messages that apply for temporary concerns on Ford’s part, may at some point become a TSB, or may just disappear. They also publish GSB that typically apply to procedures across multiple car lines.
Figure 1 - Motorcraft – PTS login webpage
My disclaimer right up front so that we are all on the same starting point. I am going to make a few assumptions about your skills and access to information. First, I am going to describe things as if you’re familiar with the IDS and somewhat familiar with Ford’s Motorcraft — PTS (Professional Technician Society) webpage (Figure 1). On that page if you access service information by VIN you get an OASIS report along with service publications, if you access by year and model you don’t get an OASIS and you will get a message offering all TSBs and SSMs. This will also give you GSBs.
These GSBs may be downloaded PDF files and stored on your shops computer system, or even printed and kept in binders at your shop for future reference.
Let's get started!
As we start, I have input the VIN to my 2015 Expedition and I put in a concern about the audio system so the OASIS report comes up first and has listings for any TSBs and SSMs that may apply to my listed concern. After viewing those I can move to the TSB SSM GSB tab and view all of them that are pertinent to my vehicle (Figures 2, 3). Let’s take a look at few.
Figure 2 - PTS vehicle Identification page, use a previous VIN, by Year and Model, or use IDS to read VIN and DTCs
Figure 3 - OASIS Report that shows when using VIN or Read VIN selections
GSB 0000156 details Passive Anti-Theft Key Fob reprogramming. As you may know, programming Ford key fobs can be very easy, if you already have two programmed fobs. It is a challenge and you’ll want to have an IDS to program a Fob when you only have one. This GSB shows the fobs and the unique methods of programming each style.
Figure 4 - SSM which describes that the climate seat function has been removed from the SYNCH touch screen.
Another — GSB 0000106 — discusses accessing and using Historical Powertrain Diagnostic Codes. These are codes that are not currently confirmed or pending but have set since the last clearing of DTCs. OBD II regulations prohibit scan tools, or disconnecting the battery, from being able to erase emission DTCs from the PCM. They can be cleared and depending on the scan tool, not show up when scanning for codes, but regulations require the PCM to actually clear the codes. This typically takes 80 or more key cycles without a fault (Figure 4).
Figure 5 - As Built navigation drop down
This is a feature that can be used for concerns that are intermittent and may or may not have progressed to MIL but are not currently present. It is also not available on every Ford. There is a special icon that appears on the left side margin of the IDS screen at the conclusion of the test for PCM CMDTCs, Continuous Memory Diagnostic Codes (Figure 5).
For those of you who’ve read my postings, been to training classes that I’ve done, or have interacted with me over the past few years you know that I maintain that there are five steps that should be done to every vehicle that comes through the door of your shop and into your bay:
1. Confirm the concern exists as described on the RO.
2. Good visual inspection
3. Check service publications and TSBs.
4. Initial non-intrusive tests
5. Network tests
Steps 4 and 5 are typically confirmed by connecting a scan tool and pulling codes. Generally speaking, if the scan tool communicates with the vehicle you will get codes if there are network concerns along with the codes that are a result of module self-testing. When the scan tool doesn’t communicate with the vehicle or you have Uxxxx codes you may wish to use GSB 0000043.
Figure 6 - As Built data for a specific 2015 Expedition
Figure 7 - TSB/GSB/SSM screen showing documents that may apply to this vehicle
In my previous article, I spent time discussing how to use IDS and PTS together to do network testing. GSB 0000043 is the one that details how to connect to a vehicle using PTS and IDS to do a live network test on the vehicle. By connecting the IDS to the vehicle, and then logging into PTS, you can do a live network test and monitor whether or not the modules in the vehicle respond when the website pings them and you can do the Ford Wiggle test to see if modules stop or start responding on the network. It’s very cool. You can read about it in more detail in my previous article and the GSB describing this (Figures 6, 7).
Analysis best practices
The starting point for analysis of any vehicle is service publications; I prefer OE access. Ford sells access by the year, the month, or for $21.95 for 72 hours of access. With this access you can get to everything Ford provides their dealer techs to analyze the vehicle, including the ability to connect IDS to your vehicle via the web using Ford’s servers and connecting to PTS. The other access you get is to As Built Data which may be needed during reprogramming modules.
Some boilerplate “this is how you’re expected to do things.” Whenever testing, programming, reprogramming, making calibration changes, best practices are:
On your IDS laptop make sure that Windows is set to Never go into screen saver or to sleep or to turn off the hard drive(s). It is also a good idea to turn off Automatic Updates, you want to control when that happens.
Set the Ford websites in Internet Explorer to trusted and allow data access across domains
Use the USB cable to connect the VCM-VCM II to the laptop
Use an ethernet cable to connect the laptop to the shop’s Internet
To really be safe have your IDS laptop connected to power
Connect a clean power source to the vehicle to maintain sufficient voltage to keep modules awake
Always run a network test to make sure modules can communicate with each other. A new module that has not be programmed should be able to pass a network test and communicate with IDS
When having problems with network communication, it worked before and now doesn’t, try disconnecting the VCM from the DLC and reconnect.
When you log into PTS and input a VIN or use the self-identity method, you will first get an OASIS report. This report details the history of the vehicle and includes warranty repairs, service actions, and possible TSBs or SSMs that may apply to the vehicle based on DTCs or symptoms you have input (Figure 8).
Figure 8 - The Adaptive Fuel Viewer GSB Listing
As you can see in this image there are multiple articles, TSBs, SSMs and GSBs available for this Expedition. And, no, I don’t expect that you’ll take the time to read every one of them while the customer’s car is on your bay. I do expect you to review those that are listed that may be related to the customer’s concern. I also expect that you will note the GSBs that you may wish to download and use.
Figure 9 - The Adaptive Fuel GSB
I have input my 2015 Expedition and look at this interesting SSM that has popped up. In the most recent SYNCH update Ford as removed the ability to control the climate seats from the touchscreen. There’s a change which I’m sure has caused Ford dealer techs some heartburn dealing with customers who upgraded the systems and their control is gone. Made me wonder (Figure 9).
I’ve already mentioned a number of GSBs, let’s be a little more detailed with two more GSBs today.
Figure 10 - The Historical DTC Icon that may or may not be available
The first is GSB 0000017, posted in 2015, Adaptive Fuel Viewer. I was very excited when I first saw this as I’m thinking, “Wow, I can finally see LTFT in the different operating blocks without driving the car and recording them, how cool is that?” (Figure 10)
This GSB explains that starting with “certain” 2013 vehicles there will be a navigation button and Datalogger screen for viewing historical LTFT. Unfortunately, the key here is the word “certain”. I owned a 2013 Flex with the 3.5 Ecoboost. It didn’t have the option. When I traded the Flex for a 2015 Expedition, 3.5 Ecoboost, I figured I would find it on that vehicle, no such luck. Which vehicles have this option seems to be a closely guarded secret, which may explain why it took until 2015 for Ford to produce a GSB on something that started with the 2013MY. Unfortunately, I have not been able to find a Ford with the Adaptive Fuel Viewer option for use in this article (Figure 11).
Figure 11 - The Mode $09 screen showing data PIDs with Ignition Counts and monitor completions since last KAM reset or PCM reprogram
If you’re working on a Ford that doesn’t have this option, you will need to view adaptive fuel the way we’ve done it for the past 22 years, by doing a road test. Set IDS to take a two-minute recording and then starting from a stop accelerate up to about a 20-30mph cruise, then accelerate up to about 50-60 mph cruise. Review LTFT in those different operating conditions.
For those of you who are new to drivability analysis using Fuel Trims, look up this GSB on PTS and you can read the whole article. Ford has been training their dealer techs to use adaptive fuel trims, LTFT, to search for patterns as a quick way to analyze the likely cause of drivability concerns for 20+ years now.
There are examples of the most common patterns, for common concerns. For example, if LTFT is negative at idle, comes to a more normal reading off idle, and then goes positive at cruise, we’re looking at the most likely symptoms of a contaminated MAF.
GSB 0000150: Various Vehicles — Module Programming and Reprogramming Procedures
This GSB details the process for recalibrating and programming new modules. It is 21 pages long so let me pull a couple of points that you’re likely to use.
GSB 150: Recalibration of Existing Modules: Tire size – Axle ratio
I had a 2013 Flex and it was equipped with 20” factory rims. The tires that were on the car when I bought it used, were great tires for dry and wet pavement but nearly worthless on snow. After some initial research I found that most tire manufacturers don’t make snow tires to fit a 20” rim. I ended up buying a second set of wheels which were 18” diameter to fit the snow tires. This was and is the recommended practice by even the aftermarket tire sites.
Different diameter rims, different tire diameters, and of course new TPMS sensors. 20+ years ago it was a swap without concern, maybe the speedometer was a little off, and TPMS didn’t exist, but hey, it’s just for a few months don’t worry about the speedo. In today’s world how many issues might come up due to different tires? Will fuel economy be affected? How about ABS? Transmission shift patterns? Maybe no problems, maybe some?
Figure 12 - Typical CMDTC test results screen
Figure 13 - Navigation panel showing Module Programming access point
Those of you with tire experience are already thinking that if they did it right by changing the tire profile the new ones, everything will be pretty close and you’re right, they did. The 20” rims had a 45 profile and the 18” rims had tires with a 65 profile. But… this vehicle has the option of recalibrating for different diameter wheels and tires. I went in and changed tire size to the 18” set that I installed. When I put the 20-inch rims back on I went back in and set it back to the 20” numbers. Let’s look at a few screen shots from my Expedition on how that was done.
Figure 14 - Module Programming sub-menu to do specific tasks
Figure 15 - Programmable Parameters selecting Tire Size / Axle Ratio will get you to the screen where you can reset tire size to keep speedo and other modules that use vehicle speed getting accurate information.
Once IDS is connected go to the main menu and select MODULE PROGRAMMING. This brings the next submenu, and there are four options. To get to the tire menu you select: PROGRAMMABLE PARAMETERS. This brings up the submenu with your available options, why Tire Size – Axle Ratio is listed twice… I don’t know (Figures 12, 13, 14, 15).
Figure 16 - Warning screen that IDS may ask questions and you may have several screens go by once you implement the changes.
My Flex only had the option of changing tire diameter, on my Expedition I can set tire diameter but as you can see, I also have the option of four different axle ratios. The current ratio has the “*” alongside it and to change the ratio you simply highlight the new ratio, press the blue checkmark icon in the lower right, and you’ve changed the ratio (Figure 16). You may be asked to confirm your choice and may also be reminded to clear codes. It is typical to get multiple Uxxxx codes when recalibrating, reprogramming, or replacing modules. IDS will shut the module off during reprogramming and those modules that are expecting data will not see it on the network… the result? Uxxxx codes.
Why you want to follow best practices
While working on my Expedition for this article I ran across an interesting thing the vehicle did. Look at the screen shot and notice that I have a screen full of Uxxxx codes. As I was working on the vehicle trying to scan data, which I had done doing successfully, as I tried to connect to get to KOEO, my vehicle has the push button ignition, I started getting message after message that various modules were being shut down. As they did U codes started popping up. My best guess as to what happened is that after working on the vehicle KOEO, the system voltage dropped too low and, in an effort, to maintain enough power to start the vehicle, it began to shut off modules to save energy (Figure 17).
Figure 17 - Next Screen confirming VIN
I came to that conclusion because I forgot one of the Best Practices cardinal rules about working on a vehicle when doing module testing, connecting a clean power charger to the battery positive and a known good body ground point. I did that and the modules stopped shutting down. I had many codes to clear but after clearing and using the charger, the system worked as it is designed.
GSB 150: Using MODE $09 to check for aftermarket programming and monitor completion
An interesting section in this GSB is the information about what is visible when checking Mode $09. While this may be more valuable to a Ford Dealer Tech this screen and information is a back door into possible tuning modifications that have been done by the vehicle owner. The PID is IGNCNTR, which is telling you how many times the ignition has been turned on since the last PCM reprogram or KAM reset (Figure 18). Techs can find if the vehicle had performance chips or other PCM modifications done by aftermarket shops or the owners. Looking at my Expedition you can see that it has been a long time since KAM was reset with 5189 starts since last reset.
Figure 18 - Axle ratio change screen
The other PIDs indicate the number of times that OBD II monitors have completed. You will notice that the numbers are different for different monitors. It is true that all monitors are enabled to complete every time you start and drive the vehicle. What is also true, enabling to run does not equal completion. For the non-continuous monitors in addition to being enabled at engine running and temperature above 160 degrees, there are specific driving conditions that need to happen as well. I was testing that to see what qualified as an OBD II drive-cycle, I got everything ready and jumped on an expressway, I drove for an hour at 70mph and not a single non-continuous monitor completed. I got off the expressway and drove in an urban area and all of them completed within 2 miles.
GSB 150: Programmable Module Installation
What is the process for replacing a module? After analysis has determined the need for a new module the replacement process goes like this:
Initiate an IDS session
From the main menu select Module Programming
From the next menu select Programmable Module
Follow the prompts to the module you’re replacing
When it tells you to do so replace the module
When you initially connect IDS to a vehicle it does a network test and inhales data from each module on the network that responds to it. It does this every time you connect to vehicle. When you’re done working on the vehicle you are given three options for closing the session. HOLD Session which keeps vehicle information including any recordings in a folder on the laptop. COMPLETE Session, this keeps the basic information about the vehicle but deletes any recordings you may have made. DELETE Session is the third option.
Figure 19 - The result of the vehicle shutting down systems to save battery power
I recommend that you only HOLD or COMPLETE sessions until such time as you’re sure you won’t see the vehicle again for the current concern. Selecting HOLD or COMPLETE also allows you to log off while you do any R&R or other work on the vehicle and frees IDS to be used on other vehicles during that time (Figure 19).
This is important for doing network and module work because what IDS did was to inhale the information from the original modules and store it in memory. When you replace the module, it exhales that programming into the new module. In some cases, the software in the old module is lost or corrupt, that is when you need to use AS BUILT data to reprogram the module.
It has been my experience that replacing a module or flashing the PCM is a very straightforward process when using IDS and doing so with a subscription to Motorcraft-PTS. You follow the prompts on IDS and it does everything for you except clearing codes, although I have experienced it doing that after a programming event. I did have one experience when I was asked for As Built data to complete replacement of a module.
Figure 20 - IDS session logout screen with the choices
To get AS BUILT you go back into PTS and OASIS and select AS BUILT data and it will walk you through the process by either giving you a file to download and then upload into IDS which will install it for you, or you may be asked by IDS to input the data as printed (Figure 20).
One more quick comment, and this detailed in the GSB and that is when flashing or programming fails. I have blown out the programming of a number of modules over the years. Ride Height on a Navigator, the ABS on a Hybrid Escape, as the GSB describes and what I did in these various instances was to simply start over, make sure the vehicle had good clean power and start the process over. Often that includes removing the IDS and VCM from the vehicle and then reinstalling and reconnecting.
I am well over the expected number of words for an article and I could still go on for several more pages, perhaps MotorAge will have me do a Part Two in a coming issue. Let me wrap this up with a suggestion. The only way you become familiar with and an expert at running IDS is to use it and play with it. The only, or perhaps the best way to find out about these GSBs is to use the Ford website and explore it.
Most of these GSBs appear on any Ford that you input into PTS even if only by year and model. You can review them and download them for use at a later time and to use as practice guides. Find a Ford you can spend some time with, follow their instructions, and when you have a customer that need a key programmed, an intermittent concern currently without codes, the need to replace a module, or need to change tire size when you swap snow-summer wheels and tires you can do so quickly and you too, will be an Enhanced IDS User.
Advanced-Driver Assistance Systems (ADAS) — if you haven’t heard of this term yet, you will!
ADAS is an industry-invented category that includes all those things that help keep vehicles safe on the nation’s highways. Blind-spot monitoring, pedestrian detection, adaptive cruise control and emergency braking are just a few features that fit into this category.
While the category may be new, the features it represents are not. Forward collision warning systems were appearing as early as 2001 as options in high-end models. By 2008, which is considered to be the older end of the “aftermarket sweet spot,” ADAS-related features were found on some mainstream as well as luxury models from 18 manufacturers.
You may be asking yourself, “So what? What does ADAS mean to me?” And that’s a very good question. Whether you’re an early adopter who is ready to jump into the ADAS repair world or whether you’re more passive and taking a wait-and-see posture, you’re going to be affected.
First, here’s a little more detail about ADAS and how it all works. Depending on the feature set available on a specific vehicle, an elaborate ecosystem of cameras, radars, laser assisted radar (LIDAR) and ultrasonic sensors (similar to SONAR) feeds information into on-board computers. These powerful computers interpret all that information and — using some artificial intelligence wizardry — enable features that fit into the ADAS category.
The array of sensors, cameras and radar/LIDAR componentry that supports each feature can vary. Most of the time, for example, adaptive cruise control will be supported by a forward-facing camera as well as a radar or LIDAR system, and information from legacy inputs, such as vehicle speed. The information from these inputs is fed into an on-board computer that uses them to deliver the driver’s desired speed, while watching for vehicles in front that might require a speed adjustment (up to and including an emergency braking countermeasure).
Many vehicles rely on both the radar and camera to ensure safe operation. In discussions with one vehicle manufacturer, they explained that their forward-looking radar was very capable of identifying an object in front of the vehicle, but it was not so good at identifying what the object was. They explained, “It could be a manhole cover, or it could be a small child.” So in their model, the radar detected an object, then the forward-looking camera was responsible for validating the object was there, as well as identifying what the object actually was (and if it is safe to drive over it).
For these systems to function as intended, many of the sensors must be kept in calibration. We’re used to that — if the throttle position voltage is out of whack, the powertrain controller believes the accelerator is partially down, right? The challenge with ADAS is that these sensors are all too easy to get out of calibration, and a technician may unknowingly cause that to happen.
At this point, you’re hopefully seeing this as a huge opportunity for shops! These features, which are loved so much by the driving public, are going to carry additional cost to properly maintain the vehicle. But before you put that into your 2019 business forecast, make sure you are prepared.
First, there’s an investment required to get into the game. Many of the calibration procedures require specific targeting systems. Several companies now market such kits, with good vehicle coverage. So that’s a solvable problem – but as with any other shop investment, you should evaluate the opportunity to gauge the right time to purchase. Ask yourself how many vehicles you’re seeing regularly that likely have ADAS features on them and if you can market the service to grow the business, etc.
The other, perhaps larger, issue to overcome is the problem of space. The average space required for proper calibrations is about 32 feet long by about 45 feet wide. And that means empty space; you can’t have posts of lifts or other objects in that space, as during a calibration the components being calibrated could “lock on” to the wrong object, throwing off the calibration. Some vehicles with 360-degree camera systems require much larger spaces. And the calibrations typically can’t be done outside, as the sunlight can adversely affect the calibration.
Even many new car dealerships are struggling to meet the space requirements. If you have the space in your shop, you can rest assured some of your competitors won’t, which puts you in an enviable position to drive new revenue for your shop. “Hub and spoke” relationships are already blossoming from these needs. In these relationships, shops willing to invest the money and space to support ADAS recalibrations provide those services to nearby shops that may not have the resources or space available to do them. Collision shops are another immediate potential customer, as many of them sub-let these services and are eagerly looking for providers to perform these calibrations.
For those shops that can’t — or don’t want to — get into the ADAS calibration business, don’t stop reading! You’re still impacted. As mentioned earlier, many of those sensors, cameras and radar/lidar components need to be kept in calibration, and many of them are (or are nearly) in plain sight and get in the way of non-ADAS repairs.
Let’s say you have a 2017 Cadillac in the shop. A rock has hit the A/C condenser, and the refrigerant has leaked out. Because it’s not a defect, it’s not covered by warranty, so it’s in your bay. You have the right parts in hand, and you’re performing the R&I procedures. Referring to the manufacturer’s service information, you follow the proper steps to get at it, and then there it is — Step #7:
“Remove the forward range radar module, if equipped.”
It looks pretty straightforward. The R&I actually is pretty easy, especially in the context of the rest of the job on this particular car. But take a close look at the detailed instructions and the fun comes during the reassembly. The last step states, “For programming and set up, refer to Control Module References.” And there are the steps to perform the recalibration when needed. You get lucky with this one — no special targets or fixtures are needed. The calibration is “dynamic,” meaning it will self-learn if the calibration procedure is carried out correctly. It is kicked off using a scan tool, but then reality hits. Per the manufacturer instructions:
“Drive the vehicle within the following conditions for 10-30 minutes or until calibration is complete. The ‘Service Driver Assist’ message will turn off when calibration is complete.
Drive at speeds greater than 56 kph (35 mph)
Minimize tight curves
Avoid extreme acceleration or deceleration
Follow one or multiple vehicles (Typical vehicle traffic is sufficient, but vehicles 30m – 50m (100 – 165 feet) away are most effective at decreasing the calibration time)
Drive in an environment that has stationary objects on the side of the road (street signs, guard rails, mail boxes, fences, etc.)
Verify proper calibration by observing that the “Service Driver Assist” message turns off within 10-30 minutes of normal driving.”
While the conditions outlined likely work well in much of the country, I can think of many places where it’s going to be very difficult meeting those requirements. Have you ever tried to stay above 35 mph in Los Angeles or DC — or a number of other high-density areas in the U.S.? And, what shop has someone they can dedicate to 10-30 minutes per car to carry out the required “calibration drive?”
And this is just one example of many different scenarios possible. However, ignoring the calibration step is not an option. Consequences could be disastrous — to the occupants of the vehicle, vehicles around it and ultimately to the shop that performed the last service which could have compromised the system.
So what to do? One of the major issues in all of this is to understand what you’re up against before you take on the job. Because these features and components are not standardized, they can be called any number of things — and the calibration requirements can require a bit of research to uncover.
At Mitchell 1, we’ve done at least part of this work for you. There is a new “Driver Assist ADAS” button in the ProDemand repair information software. Selecting it will present a table listing the different components and features that may be installed on the vehicle in your bay. It also indicates if and when those components might need calibration, and links to information about how to perform the calibration if one is needed. In addition, diagnostic, R&I procedures, wiring diagrams etc. are all available. While it doesn’t solve all the challenges, it educates technicians before they get into the job, which is important.
As for the business of calibration, it will be up to every shop to decide if they can and want to take this work on themselves, or seek out a shop that can do it for them. Either way, ADAS appears to be here to stay!
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