Hello, I m Mike Sculthorpe, welcome to the March 2015 Emerging Issues Program.

Transcription

1 D March 2015 Emerging Issues Hello, I m Mike Sculthorpe, welcome to the March 2015 Emerging Issues Program. The goal of Emerging Issues is to give you and your dealers a Heads-up on what you ll be seeing at your facility in the near future. During the program today we will cover the latest service topics from Brand Quality and Engineering as well as answer questions from techs in the field. Send your questions or comments to EI@raytheon.com We do our best to answer all of our . And of course we are always interested in hearing about topics you d like to see covered in a future program. To get credit for watching this program you must pass the test, I ll give you instructions for how to access the test at the end of the program. Also, the SC symbol in the lower right corner of the screen identifies topics that should interest Service Consultants. Please be sure to let your Service Consultants know when you find content for them in the program. First up Top Stories. TOP STORIES In the mail bag this month we have a question from Billy Santiago at Beck Chevrolet in Palatka Florida. I just finished looking at Emerging Issues Video for Feb / D. My question is for this Annual Preventative Maintenance Check on Police Package Vehicles. In the past when we replaced fan motors we also replaced fan blades. Now being that we are doing Maintenance Check, is it necessary to replace the fan blade also with motor? Or only replace fan blade as needed? Hey Billy, I checked with Brad Thacher, the Brand Quality Manager for the Impala Police vehicle and he said that there is no change in the repair procedure. If either of the fan motors fail the test outlined, the motor should be replaced per instructions in SI. Doc ID covers the repair for 2006 through 2008 vehicles and it states that after removing the fan blade it should be discarded.

2 Doc ID covers the 2009 through 2015 Impala Police vehicles and also directs you to discard the blade after removal. So the answer is replace the blades any time you replace the motor. Next, I wanted to let you know that the MDI 2 is about to be released. There are several new features you should know about. The MDI 2 will use a USB Wi-Fi adapter instead of the compact flash Wi-Fi adapter used in the original MDI. This allows a point to point Wi-Fi connection between the MDI 2 and your computer, no need for a wireless router! This should eliminate some of the connectivity concerns you may have had in the past and provides a more secure connection for programming. MDI 2 uses a type B USB connector which is more durable. It also uses USB 2.0 which will provide faster communication There are no internal batteries in this unit although it can be powered through the DLC connector or the USB connection. It also has the capability to support additional vehicle communication protocols that may be used in future GM vehicles. This includes CAN Flexible Data Rate and Diagnostics over Internet Protocol. We do not know if GM will be using these busses, but it s nice to know that the MDI 2 is flexible for future growth. Here is a quick look at the USB cable. It has a Type A connector on the vehicle end and a type B connector on the MDI 2 end. The DLC cable may look similar but won t connect to the original MDI and the original cable won t connect to the MDI 2. The last components are the self-test and AC / DC adapters used to test the DLC cable and configure network connections. The MDI 2 should be available from the GM Tools web site sometime in March. The original MDI will continue to work on vehicles into the future and will continue to be supported, but new purchases should be the MDI 2 to get the advantages we discussed. Our last Top Story is this month s New World Class Technicians. Neil Foster at Cody Chevrolet Cadillac in Montpelier Vermont Chris Riser at Bill Pierre Chevrolet in Seattle Washington

3 Jonathon Constantine at Cavenaugh Auto World in Walnut Ridge Arizona and Wesley Sander at Westfall GMC Truck in Kansas City Missouri Congratulations to all of you on this hard earned honor. Let s move on to our Featured Topic. FEATURED TOPIC This month s featured topic is Loss of Isolation or LOI in Hybrid vehicles. We are going to take a look at what LOI is and what it means. We will also review how the vehicle tests for LOI and how SI diagnostics safely help determine the cause. But before we get started, remember SAFETY ALWAYS COMES FIRST! Nothing we are presenting here is a substitute for SI, training and an understanding of the systems and tools used. If you have not completed the available high voltage training DO NOT attempt to make any repairs to these systems. Always perform the applicable High Voltage Disable Procedure as published within GM Service Information before servicing high voltage components and or wiring. Always wear the proper Personal Protective Equipment as directed in Service Information until the disable procedure validates that there is no high voltage present. There is always a potential for high voltage within the High Voltage Battery assembly so continue to wear all PPE while the battery case is opened. Isolation can be defined simply as separation. We use that term when referring to the high voltage system, it means that the high voltage system has virtually no contact with the low voltage system or chassis of the vehicle. In vehicles like the Volt, ELR and Spark EV, the high voltage system is isolated from the vehicle. The High Voltage battery and each High voltage device have both positive and negative cables, or in the case of the drive motors, 3 high voltage AC cables. The vehicle chassis is NOT used to supply a return path for high voltage at any time. A Loss of Isolation occurs when the positive or negative high voltage DC circuits or any of the high voltage AC phase circuits lose this isolation to the vehicle chassis. In very basic terms, LOI is a short between the high voltage system and chassis. But, because this is high voltage, a breakdown in the insulation could allow voltage potential to jump to the low voltage system or the chassis without having a direct short between the two. This is similar to an HEI spark jumping from a pinhole in the plug wire.

4 The High Voltage systems use 2 different tests to determine Loss of Isolation. These are referred to as Passive and Active Isolation testing. The drive motor generator power inverter module, often referred to as the power inverter module or PIM, contains three motor control modules. Those modules test for isolation between each high voltage bus and vehicle chassis whenever high voltage is present at the PIM. This is called a passive test because the system is just monitoring a voltage differential. If the motor control modules detect an isolation loss on any high voltage bus, the hybrid/ev powertrain control module 1 reports a fault. A detected loss of isolation may be caused by any cable or component in the high voltage system. Be aware that some high voltage components contain internal switching or inverter circuits that can interrupt a portion of their high voltage circuitry. If one of those components, for example the passenger cabin heater, is OFF, its complete internal circuitry is not being monitored. So, anytime you are diagnosing a loss of isolation, it is possible that the fault will not show up if the faulty device is not activated. Active isolation testing is dedicated to monitoring the internal Hybrid/EV battery pack and the charging system HV circuits. Most active isolation testing occurs just after the vehicle is shut off following a drive trip and after the main high voltage contactor relays open. Active isolation testing of the High Voltage charging circuits will occur if the charge cord is connected to the vehicle when the test is performed. To perform the test, the battery energy control module, or BECM, injects an AC signal on to one side of the high voltage system and monitors the return signal on the other side. The difference between the injected and returned signal is used to calculate a resistance-to-chassis value. So, when you view the Isolation Test Resistance scan tool parameter, you are looking at the resistance-to-chassis calculation made by the BECM during the last active isolation test. It is not a live data parameter. Now let s take a look at how LOI is diagnosed. Significant changes were recently made to those documents to provide an easier to understand diagnosis. We put a video together to show you some of the steps. Let s take a look. VIDEO GDS 2 can provide information concerning a loss of isolation (or LOI) and should be a preliminary step during diagnosis. Once the vehicle is built, select Module Diagnostics,

5 Hybrid Powertrain Control 2, Data Display, and Vehicle Information. In the future, Vehicle Information may be relocated and renamed under System Diagnosis and HV Isolation. Vehicle information is a bundle of many data parameters from multiple modules (relevant to isolation diagnosis) all collected in one screen. Because this is a new feature, be aware that GDS 2 may glitch at times when entering this list AFTER leaving another list. If some parameters don t show, simply back out to the main screen and navigate directly back to vehicle information. You may notice that only Drive Motor Control Module 1 is listed in this screen. Drive Motor Control Module 2 and the Auxiliary Pump parameters would show the exact same values so they were left out for simplicity. The 2 parameters highlighted here are new. The first is Isolation Voltages Delta. This represents the difference between the positive and negative isolation voltages. This information is useful for quickly determining the current amount of isolation in the system. The second parameter is Isolation Voltages Ratio. The ratio of the isolation voltages is useful for determining how close the passive isolation DTCs are to setting. DTCs P1AF0, P1AF2 and P1E22 are calibrated to set at a ratio of 4.53 to 1. A table in the Loss of Isolation on the High Voltage Main Bus document shows how varying resistances between the high voltage system and chassis will affect the Positive and Negative isolation parameters, as well as the Delta parameter. As you can see, a slight difference, or Delta, between the positive and negative isolation parameters is normal. As the resistance to chassis decreases, the delta voltage increases. The greater the delta, the less isolation exists between high voltage and the vehicle chassis. During this diagnosis, we are directed to observe the delta parameter with the vehicle on. If it is greater than 15 volts, the diagnostic directs you to observe and record which components are active.

6 Because some high voltage components contain internal switching or inverter circuits that can interrupt a portion of their high voltage circuitry, it is important to record which components are active when a LOI is observed. If one of these components, for example the passenger cabin heater, is OFF, its complete internal circuitry is not being monitored. If the fault is in those circuits, the LOI may not be observed until the device is activated. The High Voltage Component Test Methods table in doc ID lists the best test method for each component. If the diagnostic directs you to Circuit System Testing, the High Voltage system must be disabled using the procedure listed in Service Information. Always wear High Voltage Insulation gloves until you have determined that a high voltage exposure risk is no longer present. Further testing of components and cables requires an Insulation Meter which will apply a high voltage to the circuit and measure the return voltage in order to determine loss of isolation. A regular DMM WILL NOT WORK! Without this high voltage push, it is very possible that the fault will not be found. Carefully review the Troubleshooting with an Insulation Multimeter document in SI. Whether you are using the GM-recommended EL Insulation Multimeter, or a different insulation meter, it is very important that you read the instructions and understand the proper operation of that meter. Be sure to plug the leads into the correct ports on the meter. If the EL was used during the disable procedure, the leads are not correctly set up for insulation testing. The meter may seem to be working, even showing continuity, but it is not measuring insulation. Install the correct leads into the ports on the left side of the meter face. The ports are labeled Insulation Turn the rotary dial to the insulation setting. Do not use the voltage or resistance settings. Ensure the meter is set to the 500 volt range. If it is not, press and release the range button on the meter face until 500V show in the display. 500 Volts is the closest to the actual battery voltage and therefore will give the most accurate test results. Set the leads down so they are not attached to anything. Press and hold the test button and review the display. This will familiarize you with how the meter displays an infinite measurement. The EL will display 550mega ohms when measuring an open circuit while set to the 500 volt range. This is similar to the Fluke 87 displaying OL for an open circuit.

7 Next, with the probes connected, press and hold the test button. This will familiarize you with how the meter displays continuity. The EL will display zero ohms. When performing insulation testing you need a good reference connection. When possible, use an alligator clamp to attach the negative lead. At certain points in the diagnostic, the reference point will be to vehicle chassis. When testing cables, the diagnostic will direct you to attach to the cable shield termination at the connector, NOT to the chassis. This is because cable testing is done with the cable disconnected at both ends. Cable LOI is typically to the shield wire. Once the cable is disconnected from the circuit, the shield wire is no longer connected to vehicle chassis. So connecting the meter negative lead to chassis won t provide accurate results. Always test your return connection prior to insulation testing. If it is attached to chassis, touch the second lead meter lead to another point on the chassis and press and hold the test button. The meter should display zero ohms. If a cable is being tested, the negative lead should be attached to the shield circuit. In this demonstration we re testing the AC compressor and leads. Touch the second meter lead to another point on the shield and press the test button. The meter should display zero ohms, indicating a good connection. Once the return connection has been verified the insulation test can be performed. SI diagnostics direct us to test for 550 mega ohms between X4 terminal A and chassis ground as well as between X4 terminal B and chassis ground. Chassis ground can be used because the cable is still connected to the AC compressor and the compressor is connected to chassis. With the negative lead attached to chassis ground, the connection is tested by touching the positive meter lead to another chassis location and pressing the test button. Zero ohms shows we have a solid connection. Next, connect the positive meter lead to one of the AC compressor connector terminals. Press and hold the test button to perform the insulation test. When testing components with large capacitance or inductance, such as the AC compressor, it may be necessary to hold the test button for a few seconds until the maximum resistance value is displayed. Wait until the display stabilizes before releasing the test button.

8 This harness has been removed from the vehicle to better illustrate proper testing. Begin testing the connection to the shield by connecting the negative lead to one end of the shield. Touch the positive probe to another point on the shield, in this case the opposite end of the cable. Press the test button and review the results. The display should show zero ohms. Now, move the positive probe to one of the high voltage terminals and press the test button again. The display shows 550 mega ohms or an open circuit. Move the probe to the other high voltage terminal and press the test button again. The results are the same, 550 mega ohms. This cable is passing insulation testing. But a closer look at this harness shows that it has been damaged. The cable insulation has been removed and the shield is exposed and damaged. If we use a water bottle to spray the cable down as directed by SI, the test results may change. Touching the probe to the terminal and pressing the test button will check to see if the added moisture makes a difference in the results. As you can see the cable now fails isolation testing. The Insulation Multimeter just showed a failure in this cable, but if we bring in our trusted fluke 87 and test for resistance between the shield and each cable, the meter displays OL in each case. Using the wrong tool for the job would have led to a diagnostic mistake. As you saw, we were able to get the cable to fail an isolation test using a spray bottle which shows that running the vehicle through a car wash with under-body spray may be enough to get an intermittent to act up, but it also brings up a good point about visual inspection. If a high voltage cable is damaged, it should be replaced even if it does not fail isolation testing. In this case the cable was damaged by rodents. The customer saw the damage and wrapped the area in electrical tape, making the damage harder to see and helping to hold moisture against the damaged area of the cable. In the video we told you that the Vehicle Information screen in GDS 2 actually pulls information from multiple modules. This is the first time that this has been done but I think we will see this same strategy used on other vehicles and systems in the future. Not having to switch between data lists when diagnosing can be a big help. Also, I m sure the glitch we described when showing the vehicle information list is only because this is a new method and they will get that corrected in the near future. I tried to get it to act up but all parameters came up each time. As you saw, there is a test button on the face of the EL to trigger an isolation test. There is also a test button on the positive probe that does the same thing. This button is more

9 convenient to use in many situations, allowing you to hold the probe on a terminal and run the isolation test with one hand. Well that wraps up our featured topic for this month; What s Hot For Cars is next. WHAT S HOT FOR CARS To start cars this month we have a reminder about towing. PI0844 has some recommendations for towing or transportation of 2013 through 2015 ATS and 2014 and 2015 CTS Sedan. When recovering or transporting a Cadillac ATS or CTS, the under vehicle components may be damaged if the recommended towing and securing steps are not followed. These vehicles should only be transported on a flatbed carrier. If it is necessary to use the flat bed mounted winch to recover the vehicle, use the following steps to attach the vehicle to the recovery winch. Remove the recovery tow eye, which should be secured in the rear compartment storage area. Carefully open the cover in the front or rear fascia using the small notch on the lower edge. Thread the tow eye into the socket by turning it clockwise until it stops. Only use the tow eye to attach a winch cable to the vehicle. Once the vehicle is on the flatbed, secure it to the bed using a nylon strap type harness over all four tires. These harnesses must be secured as shown. DO NOT hook, pull or secure the vehicle using any of the under body or suspension components, damage to those components may occur. Ensure this information is provided to your towing personnel or sublet towing company to prevent damage to the vehicle. Next, If you are diagnosing a 2012 through 2015 LaCrosse with the keyless start system, RPO ATH and a customer concern that when the key fob unlock button is used to unlock the door the start button does not respond so the vehicle cannot be started, PIC6060 may help. The DIC may display a Remote Learn Pending Please Wait or Ready for Fob Three message and DTC B , B and or B may be set.

10 To duplicate the concern, exit and lock the vehicle. Wait 5 minutes and then depress the unlock button on the fob 3 to 5 times within 10 seconds. Enter the vehicle and look for either message to be displayed on the DIC. As a quick diagnostic test, use the key to check the rotation of the driver s door lock cylinder. If the key rotates more than the normal 90 degrees when unlocking, the vehicle may have been assembled with an incorrect door lock cylinder to latch rod. In this picture, the yellow rods are for the Malibu and the purple are for the LaCrosse. The rods in the vehicle only had a small paint dot and many times it is not present after assembly. The lock cylinder rod is circled. Other than lock cylinder rotation, the best method for distinguishing the 2 rods is their shape. Number 1 in this picture is the correct rod for the LaCrosse. Rod 2 is for the Malibu. The Malibu rod has a much sharper bend. The 12 volt start stop system on the 2014 & 2015 Malibu and 2015 Impala has some unique features that some customers and technicians are not aware of. On the technical side, this can lead to incorrect diagnosis and replacement of parts for normal conditions. So let s take a look at how the system works. The Stop/Start System is automatically activated each time the ignition switch is turned on. It improves fuel efficiency in stop/start driving because the vehicle automatically shuts off the engine under certain conditions such as when stopped for a traffic light. This saves fuel which would otherwise be used idling the engine. When the driver releases the brake pedal and/or depresses the accelerator pedal, the engine will restart in approximately 400 ms. Because of the increased number of engine starts, a high performance starter motor with a stronger pinion engagement mechanism is used. It also provides reduced noise levels over a conventional starter. This system also uses a primary 12V battery and an auxiliary 12V battery. The auxiliary battery is used to power all vehicle loads, except the starter, during stop/start cranking events. The main battery provides power to the starter. For the engine to shutdown, the vehicle must be below 3 MPH, with the brake pedal depressed. When the engine has been shut down by the Stop/Start System, the tachometer needle will rest at the Autostop indicator. This alerts the driver that the vehicle is in auto stop. So, when will the vehicle go into autostop or what are the enabling criteria?

11 Vehicle speed during drive cycle was greater than 2 MPH Ambient and engine coolant temperature correlation meets specified values Ambient and transmission fluid temperature correlation meets specified values Hood switch status is closed Brake pedal is depressed beyond a specific value. Approx. 27% on 2014 vehicles Approx. 14% on 2015 vehicles Accelerator pedal is in the learned home position Brake booster vacuum is greater than 7 PSI (14.25 inches) Transmission gear selector is in the Drive position Vehicle speed is less than 3 MPH Engine speed is below 1500 RPM Engine coolant temperature is less than 248 F No A/C compressor request from HVAC ECO mode only Battery voltage greater than 12 V Battery state of charge greater than 65% Coolant temp must be greater than 30 degrees F The Stop/Start Description and Operation has this table showing some of the temperature value combinations that must be met for autostop. The ECM will perform an Auto Restart if any of the following conditions are true. Conditions that will enable Autostart: Transmission gear selector is moved from the drive position Driver removes pressure from the brake or depresses the accelerator pedal while the vehicle is in the forward Drive gear

12 HVAC function is selected that requires the A/C compressor Under certain conditions a vehicle that is in autostop will Autostart. These include: Transmission gear selector is moved from the drive position Driver removes pressure from the brake or depresses the accelerator pedal while the vehicle is in Drive HVAC function is selected that requires the A/C compressor Brake booster vacuum is less than 40 kpa HVAC inside air temperature changes greater than 5 F Battery voltage less than 11 V, Battery SOC is less than 73% Hood switch status changes to open So as you can see, the vehicle is going to operate differently under even slightly different conditions. Even if the customer drives the same route to work each day, it is very possible the vehicle will enter autostop differently than the day before. One of the main customer concerns is that the engine stalled. How can you tell if it really stalled or just entered autostop when they didn t expect it? Begin by talking to the customer. Yes, they did hear the engine stall at the stop light, but did the vehicle fail to restart when they took their foot of the brake? Did they have to place the trans in park or neutral and use the key to restart the engine? If the answer is No, the vehicle is probably operating correctly. Go back over system operation with the customer to reassure them that this is normal for their vehicle. For more information on the Stop/Start system, take a look at course number W, 12V Stop/Start System PI1161 and PI1401 cover fuel tanks that won t fill past 7/8 full. We have covered this repair in the past but the PI number has changed. PI1161 covers 2013 LaCrosse, Regal or Malibu LT or LTZ with engine RPO LUK, and 2013 Malibu LS with engine RPO LCV with a customer concern that the fuel tank doesn t read full, it only goes to 7/8. It now includes a fuel tank capacities table. This repair is specific to the 15.8 gallon tanks used in these vehicles. Other engines use a large fuel tank.

13 To repair this condition, replace the fuel send and the fuel shut off valve. If you install the fuel shut off valve called for in this PI in a vehicle with the larger tank, that tank will only fill to about ¾ full. So don t make that mistake! PI1401 covers 2013 through 2015 LaCrosse, XTS and Malibu LT or LTZ with a customer concern that the fuel gauge will not go to full. This repair is specific to vehicles with the larger 18.5 or 18.6 gallon tanks. To repair this concern, replace the fuel level sensor only. The same fuel level sensor part number is called for in both PIs, but again, don t install the fuel shut off valve in the larger tanks. Next up is PIC5910 which covers 2014 or 15 LaCrosse with a B124B symptom 04 stored as current in the HMI module. The important thing to note here is there is an available repair for the 2014 vehicle reprogram the HMI with the latest calibration available in TIS2Web. But if you are working on a 2015 vehicle, engineering is working on a fix and the PI will be updated when the fix is available. PIC6056 covers a long list of vehicles for a radio that shows incorrect song information when using an ipod. If the NEXT button is pressed while the device is playing, the concern will be corrected for the remainder of the drive cycle. Engineering is aware of this concern and is working on a permanent repair and the PI will be updated when that is available. Until then, do NOT make any repairs. Our last story in cars is a heads up on a no start concern on 2015 Impala VIN W. There are a couple of reports showing a tough to detect connector problem. One of the terminals in the fuel pump control module connector may be broken creating an intermittent open circuit. On one vehicle it was terminal 32 which is the B+ supply circuit, on another it was terminal 47 which is the fuel pump feed circuit. This is hard to detect so you may have to remove the terminal from the connector. Even here it is hard to see but the terminal tang that contacts the male terminal is broken off. The replacement terminal is in tray 5 of the J terminal kit. It s part number Or you could order a terminated lead. That s it for Cars. What s Hot for Trucks is next. WHAT S HOT FOR TRUCKS To start Trucks, we have an update of a story we covered last month.

14 PI1374 was just updated to remove an important statement that was not needed. This PI covers 2015 LaCrosse, Regal ATS, CTS Sedan, ELR, Escalade, SRX, XTS, Colorado, Corvette, Impala, Silverado, Suburban, Tahoe, Canyon, Sierra and Yukon with RPO I03, I04, I05 or I06. Here is the statement that was removed: Important: The vehicle modules MUST go to sleep for 5 minutes after programming the HMI module. If not, the vehicle may not have sound, blank screen, no touch response or the wrong splash screen may appear on the screen. If this happens, shut off vehicle and wait the required 5 minutes before starting vehicle again. The problem is this PI does not require HMI reprogramming, only radio programming so this statement was confusing. It would be very easy to assume that the PI was requesting an HMI module update, creating extra, unnecessary work for you. I would like to thank Andrew Kalipetis at Open Road CADILLAC in Florham Park, NJ for bringing this to our attention. He has been a GM world class technician since 2005 and Cadillac technician since Thanks for taking the time to drop us a note! Remember, for the concerns listed in this PI, reprogram the radio only. Next, a customer concern of poor heat from the front or rear HVAC system at idle on Terraza Uplander or Montana SV6 Or Saturn Relay PIC5054 may provide some help. The front heater core on these vehicles is the highest point in the cooling system. If any air has entered the system due to a leak or servicing, it will migrate to the heater core. If the concern is with the rear heater output, remember that the lines run under the vehicle to the rear heater core. Lower ambient temperatures will further decrease coolant temperature prior to reaching the rear HVAC. In either case, increase rpms to 2000 and recheck the outlet temperature. If it does increase to an acceptable range, check for and repair any coolant leaks. Then properly fill the system using the directions in SI for purging air from the cooling system using either the static fill or vac and fill procedures.

15 Also, attempt to compare it to a like vehicle. If the outlet temperatures are similar, no repairs should be made. PIT5373 covers a steering wheel airbag rattle, click or tick noise on 2015 Colorado and Canyon. You may find that resting your hand on the airbag will quiet the noise. Engineering is aware of this concern and is working on a solution. Do not replace any parts at this time. The PI will be updated when a repair is available. Also, the Colorado and Canyon may have a Rear door Ajar message, a rear door may be hard to close, or there may be a rattle noise from the lower portion of a rear door. Any of these concerns may be caused by the rear door lower striker being out of position. After verifying proper front door adjustment, loosen the two bolts on the lower rear striker, adjust the striker and tighten the bolts. Test to verify that the door closes fully. Then recheck to determine if the concern has been eliminated. Refer to PI1415 for further details. Our last item for the Colorado Canyon concerns normal operation of the door latch on this vehicle. In the February 2014 EI we covered a new style door latch on all of these vehicles: 2014 Sierra and Silverado, 2013 and 2014 XTS, ATS, 2014 CTS Sedan and 2014 Impala. Now you can add the Colorado and Canyon to the list: We have a short video to show you what has changed. Let s take a look and listen: This new design latch does not spring open when the release is activated. So, if you are in the habit of flipping the latch closed when working on a vehicle so you don t have to listen to the chime, you will need to open the latch manually when done before the door will close. Do not replace latches for a bolt that does not spring open. In the March 2014 EI, we covered damaged radiators from the 900 HD trucks being sent back to the WPC. After that story, they saw a significant drop in damaged returns. Now it is happening with the K2 HD trucks and we have been asked to get the word out again. Here are a few pictures of the parts they have received. On this one, you can see the crack along the side of the tank. This one has the side of the tank broken away. This one also has a large chunk missing. And this one appears to have been dropped on the mounting tab.

16 It s obvious that none of these parts can be tested to determine what caused the failure requiring replacement. That leaves GM wondering if the part should be warrantied or whether your dealer just warrantied a damaged part. I would be willing to bet that these parts were damaged in the return process, not by technicians but by rough handling after you turned it in. So, I would suggest that the old part be carefully placed into the box that the new part came in with all the proper packaging. Also let whomever handles warranty scrap know that GM is looking closely at radiators and to please use a little more care in the return process. The parts replaced during warranty repairs still belong to GM and engineering asks for those parts to be returned to help determine root cause of a failure. That s how designs get improved. We have a quick update on the 360 degree camera on the 2015 Escalade. New software should be released sometime in March to help improve low light camera performance for this system. Look for a PI concerning this update in the near future. This next story applies to both trucks and cars Bulletin covers General Motors New Vehicle Tire Warranty Program. It provides answers to many questions concerning what is and what is not warrantable. It also shows several examples of tires that were warrantied and returned to the WPC that are obviously damaged. These are a couple of pictures included. The damage in both is the result of extended driving on a tire that has little or no air. The second had damage to the inside of the tire. Remember that shredding of the inside may not always be accompanied by obvious exterior damage. You may have to remove the tire to determine if the tire was driven while low on air. In either of these cases, this type of damage is the result of abuse and is NOT a warrantable condition. Far too many tires that have been warrantied are returned with a description of tire separation. Tire separation is very uncommon. It would be defined as the tread material separating from the belt material. Again, GM is looking at these repairs and wants to determine root cause of failures so they can make corrections to reduce warranty cost and increase customer satisfaction. The cause and correction portion of the repair order are very important and must be supported by the returned part. When a tire is received with a screw puncturing the tread, the claim will probably not be paid. The bulletin even has a statement that reads:

17 Important: These are only a sampling of the conditions exhibited in warranty tire returns. GM is not responsible for, and WILL NOT replace tires sent in for conditions under the What is Not Covered section above. I would strongly suggest that you read the bulletin and make sure your manager is aware of its content before replacing a damaged tire under warranty. And our last story in Trucks is a heads up on a clunk or thump noise the first time any 2010 or newer Enclave, Traverse, Acadia or Outlook is accelerated after the key is cycled The noise could be mistaken as coming from the suspension or possibly engine compartment, but is probably the second phase power-up self-test of the ABS. the test begins when vehicle speed is greater than 9 mph. In most cases this noise should be considered normal but if it seems louder than a comparable vehicle, take a look at the underbody brake lines. Check for contact with another line or with the body. Isolate the lines to minimize noise. Refer to PI1402 for further details. Well, that s it for Trucks. Powertrain is next. POWERTRAIN To start powertrain this month let s look at PIP5262 which covers a Reduced Engine Power message displayed in the DIC. Vehicles covered by the PI include 2012 or 2013 Cruze with a 1.4 liter turbo engine, RPOs LUJ or LUV. The customer may state that they didn t notice any noticeable reduction in engine power because the actual power reduction is only about 25%. Also, you may not find any related DTCs stored. If this is the case, it is likely that the vehicle was run out of fuel, causing the message. Using GDS 2, display the Reduced Engine Power History Parameter by selecting "Module Diagnostics" "Data Display" "TAC Data" and "Reduced Engine Power History". If the parameter displays Engine Powered Hybrid/EV Battery Charging Unavailable the fault was likely caused by the vehicle running out of fuel. To clear the message, disconnect the battery for 5 minutes and then reconnect. Use the GDS 2, clear codes function to reset the reduced engine power history status to NONE. Test drive the vehicle to ensure the message doesn t return. Unless the vehicle is run out of fuel again, the message won t return. An updated calibration may be available in the future to correct this concern.

18 Next we have a heads up concerning oil filter cap seals that leak. On engines that use a cartridge style oil filter, begin diagnostics by checking for a gap between the housing and the cap. If a gap exists, the cap wasn t tightened properly or the seal ring wasn t installed properly. If the seal is damaged, it obviously must be replaced. If a seal is replaced under warranty, be aware that all GM oil filter housing seals are blue, as you can see in the picture on the left. If the seal you are replacing is any other color, it is NOT GM and should not be replaced under warranty. GM is looking closely at oil leak concerns and will request O-rings be returned to the WPC. Claims returning non GM O-rings will be fed back. GM requires that the oil filter cap O-ring is replaced at every oil filter change. If the oil change was done without using GM parts, the repair is not warrantable. PI1247 covers 2014 and 15 Spark equipped with a CVT, RPO M4M and a customer concern that the trans does not shift, it s slipping when cold or the RPMs are too high when cold. Be aware that CVT operating characteristics prohibits the shift to the second gear ratio until fluid temp is greater than -4 degrees F. This is done to provide improved vehicle emission and heater performance, but could give the impression that the trans is slipping or that engine RPMs are too high. Please communicate to the customer that this condition is a normal operating characteristic of their vehicle. It will not impact the designed performance or reliability of the vehicle. Share this PI with the customer if they have any concerns. PI1166 covers a slow to heat up in cold ambient temperature concern on 2013 through 2015 Encore, Spark or Trax 2011 through 2015 Cruze Or 2012 through 2015 Sonic Equipped with the 1.2, 1.4, or 1.8 liter gas engines. These smaller, energy efficient engines may not generate the same amount of heat at idle that the customer may be accustomed to when compared to older, less efficient engines. Also, a short drive under light engine load may not generate enough heat to reach normal engine coolant temperatures which would also lead to insufficient heat from the outlets.

19 The PI recommends that the Diagnostic System Check Vehicle is performed and any stored DTC should be diagnosed. Also verify that the coolant in the surge tank is set to the correct level. Don t replace the thermostat unless there is a stored DTC related to it. If after performing these diagnostic steps, no concern is noted, let the customer know that you have checked the vehicle and this condition is a normal characteristic of their vehicle and refer them to the operational tips listed in the PI. If the vehicle has a manual HVAC system, recommend to the customer that the blower be placed on medium or 3, when outside temperatures are extremely cold. If they set the fan prior to shut off, this setting will help produce more heat in the cabin sooner on a remote start as well. In these low ambient temps, the heater core can pull more heat from the coolant than the engine can produce at idle or low speed if the fan is set to a higher speed. Vehicles equipped with Auto HVAC are already programmed to use a lower blower speed during warm up. A copy of the PI can be provided to the customer to back up your findings. PIP5272 covers low oil pressure after an oil and filter change on 2014 and 15 full size trucks with the 4.3, 5.3 or 6.2 liter engines. The correct filter is a PF63, which is part number A PF 48 will fit but can cause a low oil pressure concern and DTC P0521. If the wrong filter is installed, replace it with a PF63 and recheck for the concern. Remember, PF 63 for Gen 5 V6 and V8, PF 48 for Gen 4 V8. Our last story in Powertrain is a very helpful table in the Techlink magazine. Right on the main page is a link to an engine oil capacities table. It lists all 2012 to 2015 vehicles, their engines, the oil capacity in liters and quarts and the correct oil viscosity. This would be a good one to print out and laminate for the lube rack. It provides a lot of information in one place. I hope that everyone is already reviewing TechLink magazine to help keep up on the latest available information. OK, that is all we have for Powertrain. Back to Basics is next. BACK TO BASICS In back to basics this month, we are going to take a look at the Pico Scope.

20 You may already be using this tool to diagnose vibration concerns, and it is a great tool for that, but it was originally designed as a four channel oscilloscope. GM Tools now has a Basic Lead Kit that provides flexibility to use the PicoScope as a digital scope. It is the CH BAS and includes all of the pieces shown here including 4 test leads. There is also a Starter lead kit. It has 2 test leads and an assortment of probes and clips. Now that we have covered what is in the kit, the next step is to download the software. Go to picoauto.com, click on the software tab and select the free download. PicoScope 6 Automotive software and PicoDiagnostics software will both download onto your computer. You can do this even if you don t have the scope or leads and allows you to explore a bit. The reason we are bring this up is that the PicoScope NVH kit, CH51450, will become an essential tool in the near future. Once you have this tool in your shop, we thought you would like to know what else can be done with it. Next month, we will get a little deeper into how it can supplement your diagnostics. What I would like you to do is send me your input. Do you already have the PicoScope? What have you used it for? If you don t have the scope, have you used other scopes? What questions do you have about this scope or scopes in general? I will attempt to find answers and add them to the April EI Back to Basics. Next, Fix it Right the First Time FIX IT RIGHT THE FIRST TIME Fix it Right the First Time is where we review COMMONLY MIS-DIAGNOSED symptoms one for cars and one for trucks. For cars we have concern on Cruze models. Customers may comment that there is a buzz or vibration noise coming from the dash or floorboard area, especially in the RPM range. This condition could possibly be caused by brake lines contacting each other below the master cylinder.

21 To correct this concern what you SHOULD DO is install 2 clips, part number , to the brake lines to ensure proper spacing between the lines. What you SHOULD NOT DO is replace other components without first eliminating the brake lines as a source of the concern. Next is an issue that covers all Light Duty trucks as well as Passenger Cars equipped with the 6L80 or 6L90 automatic transmission After replacing the pump cover, part number , on a 6L80 or 6L90, the transmission may have low line pressure, which can cause damage to the clutches during operation. This condition may be caused by Rust Inhibitor material in the service pump sticking to valves or plugging small orifices. The rust inhibitor causing this problem is usually a think waxy substance. To correct this condition what you SHOULD DO is remove the rust inhibitor using a solvent, light penetrating oil or carb cleaner. What you SHOULD NOT DO is us abrasive pads or submerge the pump cover in a parts cleaner with used solvent to remove the rust inhibitor. PI1404 has more details. OK, that s it for Fix it Right the First Time. I d like to thank all of you for watching today. And, as always, if you have any questions on what was covered today please send us an at EI@raytheon.com, and we ll be sure to answer them as quickly as possible. You can also use this address to make suggestions. We re always interested in hearing about topics you d like us to cover. Now, I want to give you a heads-up on next month s Emerging Issues. The April Emerging Issues will be available on the training website by April 9th. After logging on, select - Resources - then Video On Demand - Select D April 2015 Emerging Issues

22 - Or you can do a Catalog Search for this course number. To get credit for watching, make sure you take the test on the Center of Learning website. The test can be accessed in one of three ways: First, you can click on Testing then Service Technical then Know-How Seminars Or second, from the Catalog View Course page, you can click on the Test Out link. Or third, when the player reaches the end of this video, a Take Test link will appear. Click on the link to take the test. That brings us to the end of this month s Emerging Issues Seminar. We ll see you again next month. Thanks again for viewing.