Technician Polls on SI Forum. Techline News. CHANGES FROM PRIOR OVERHEAD SYSTEMS IR Transmitters are only on the Left (Driver-side) RSE Display

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1 March 2010 Volume 12, No.3 The seatback Rear Seat Entertainment (RSE) system available in the 2010 Equinox, Terrain, SRX and LaCrosse features OEM DVD screens that display video from the DVD player located in the vehicle s radio. The screens may also display video provided to the auxiliary video input jacks located at the rear of the center console. The RSE displays may be prematurely replaced due to mis diagnosis of the system. Keep in mind the following operating characteristics before replacing a display. Techline News Rear Seat Entertainment Display TIP: There is also an SPO headrest DVD system available as a dealer-installed accessory. This system is independent of the factory-installed overhead system. Refer to SI documents for diagnosis and repair of the SPO headrest system. CHANGES FROM PRIOR OVERHEAD SYSTEMS IR Transmitters are only on the Left (Driver-side) RSE Display Eight infrared LED transmitters are used to send audio signals to the wireless headphones that are included with the system. These LEDs are located on the driver-side screen, and are aimed to provide a signal to any rear seating position. Technician Polls on SI Forum continued on page 2 As part of GM s efforts to improve the support they provide GM dealerships, there is a renewed emphasis on gathering information from the field when making decisions that impact technician productivity and customer service. One way of acquiring feedback from technicians is through the new technician polls that are now being posted on the Service Information forums website at TIP: Click the Forum tab at the top of the page to log in and vote on the latest poll. If you re not a member of the Forum, you need to register for access. The Service Information Development group is posting polls on the Service Information forum under the Administration Forums to allow you the opportunity to vote on SI changes being considered. continued on page 2 Contents Rear Seat Entertainment Display Technician Polls on SI Forum Allison Transmission Fluid Leak Allison Transmission Shift Conditions..3 Full-size Truck Two-Mode Hybrid Auxiliary Pump Diagnosis Remote Start Seat Heating and Ventilation Battery Cable Connections Full-size Truck PPS Re-zero Procedure.5 Service Replacement Headlamp Skipping Audio Playback from HDD....6 Universal Garage Door Opener Connection Intermittent Electrical Conditions Fuel Line Bracket Rattle Engine or Crankshaft Installation Repeat Poor A/C Performance Slosh Noise from Rear of Vehicle Fix It Right the First Time Service Know How Service and Parts Operations March

2 Rear Seat Entertainment Display continued from page 1 During operation, the LEDs may be visible through the lens on the driverside display, but not visible from the passenger-side seating position. This is NORMAL OPERATION the illuminated LEDs are located on the driver-side only. LED transmitters are on the left display only. Cannot Receive AM/FM/XM Audio on Wireless Headphones The seatback RSE system is different from prior overhead RSE systems in that the RSA (Rear Seat Audio) system is no longer required with RSE. If the RSA system is not included with the vehicle, the audio that can be heard on wireless headphone channel 2 will ONLY be from a device (IPod, MP3 player, game system, etc.) that is connected to the rear seat auxiliary audio jacks. Wireless headphone channel 1 will provide audio from any disc in the DVD player, including DVD audio, CD audio and MP3 or WMA audio discs. Cannot Receive Audio from Device Connected Directly to the Display Video Input The yellow RCA jack on each screen is dedicated to video only. Any composite video signal (from a video game, camera, stand-alone DVD player, etc.) attached to this input will override video from the vehicle DVD or rear auxiliary jack. Any user of this input will have to access audio from the external device directly from the device. EARLY PRODUCTION ISSUES Channel 2 Audio Drops Out on Wireless Headphones The wireless headphones used on the first three months of production have been found to have weak reception for channel 2 audio. The symptom is that channel 2 audio will drop out if there is anything blocking the path between the transmitters and the headphones. Channel 1 audio is unaffected. If service is requested for this condition on vehicles built before 09/11/2009, replace both headphones with service headphones (part number ). These im - proved service or production headphones can be distinguished as having earpieces that fold flat. Improved headphones have fold-flat earpieces. Screen Squeak/Rattle Video screens used on the first two months of Equinox and SRX production may have an internal hinge attachment that may become loose enough for a squeak or rattle to be heard while driving when the screen is in the upright viewing position. All service parts in stock now have an improved attachment. Video screens in the Lacrosse are not affected. DIAGNOSING OTHER ISSUES RSE Display Blank or Inoperative A blank or inoperative RSE display is the most common customer concern. If the RSE display does not have all the necessary signals from the radio, it may not turn on. When diagnosing a blank or inoperative RSE display, refer to the RSE display Service Information as well as any applicable RSE display bulletins and PIs (Preliminary Information). Service Information includes: Document ID Video entertainment system inoperative Document ID Video display is poor or blank Diagnosis of blank or inoperative displays should begin with checking the radio for video display-related DTCs. Setting of these DTCs would typically identify a vehicle wiring (open or short) issue. continued on page 3 Techline News from page 1 A new poll with a couple of questions will be posted each month along with examples. Participants will see a tally of their voting results immediately after voting. An example from the latest poll asks about the use and location of the diagnostic fault information in SI. Each poll question is followed by an example in the SI format so you can Provide your input to SI changes by see what the proposed change will voting on the SI Forum technician poll look like. In addition, the pros and cons are provided to give you an idea why a change is being considered. Your input is important, even on what may appear to be an obvious answer from a technician perspective. By making your voice heard, the SI Development group will be able to make changes based on what is best for all users. Thanks to Dave Nowak, Jeff Flood, Rick Hill and Lisa Scott Each poll question provides an example of how the proposed SI change will be implemented. 2 March 2010

3 DVD Player Does Not Work The DVD player is integrated into the radio and separate from the DVD screen. It should be diagnosed sep arately. Diagnosis of this condition should begin at the radio. The RSE display simply shows what is sent by the radio. Other Issues If there is a mark or scratch in the LCD screen, or physical damage to the plastic housing, be sure the cause is not customer abuse. Do not attempt to repair a RSE display with a broken latch. Replace the display. Improper Use of Labor Codes for the GM SPO Headrest DVD System There are separate labor codes for dealer-installed GM accessories. The Service Information has updated labor codes for dealerinstalled GM accessories. Refer to bulletin # F. The labor code for the SPO Headrest DVD system is R9392. GM does not release an OEM Headrest DVD system, so all headrest systems should use this labor operation code. The labor code to use for the seatback RSE display is R5554. Be sure the correct labor operation code is used for the system being repaired. Thanks to Mark Friedrich, Charleen Goike and Katul Patel Allison Transmission Fluid Leak During cold weather, a small, red fluid leak may be noticed on some Silverado and Sierra 2500HD-3500HD series models equipped with the Allison LCT1000 transmission (RPO M74, MW7). The fluid leak may be at the back of the transmission by the vent. This condition may be caused by fluid being discharged out of the transmission vent during extreme cold weather (approximately -15 F or -25 C or colder), at which point DEXRON VI and other conventional transmission fluids become extremely viscous. When the viscous fluid is circulated into the vent area, it becomes trapped and is not able to drain back to the pan. As the transmission warms up, the expansion of the air inside the transmission can force the trapped fluid out of the vent, leading to small drops of fluid being discharged. To correct this condition, remove the stock vent assembly and run an external tube and vent up to the front of the transmission to a mounting bracket. The extra length of the tube will allow the expelled fluid to be trapped and later drain back into the transmission. In addition, on models, replace the transmission fluid in dicator (dipstick) with a new vented indicator. Refer to bulletin # A for additional information and installation procedures. Thanks to Al Ferry New vent assembly. Remove the top of the vent assembly. A. Top vent and tube B. Bracket Allison Transmission Shift Conditions The Silverado, Sierra; Silverado Classic, Sierra Classic; and Kodiak and Topkick equipped with the Allison LCT1000 transmission (RPO M74, MW7) may have a delayed engagement or no engagement into Drive, a delayed engagement or no engagement into Reverse, or a range inhibit with several possible DTCs. TIP: These conditions may be more pronounced in cold climates during a cold start. When DTC P0701, P0751, P0756, P0761, P0843, P0848, P0873, P0877 or P0894 set, it could indicate no or excessively low pump pressure as a result of a no prime or loss of prime condition within the transmission pump. Follow the diagnostic steps outlined in the Service Information. All of these DTCs, excluding P0894 could be set due to a fluid service/filter change, transmission service involving removing the pan, low fluid level caused by a leak, or long periods of storage. Also check the transmission fluid level using the Hot Check Procedure. Low fluid level may cause any of the listed DTCs to set, particularly during a cold ambient and cold vehicle start. In cold climates, ensure the fluid level is at the top of the HOT band. After checking the fluid level using the Hot Check Procedure, if any of the DTCs reset during a cold start, inspect the internal suction filter for possible cracks. TIP: Replacing the TCM will not likely correct any of the listed DTCs or low main line pressure. Thanks to Al Ferry March

4 Full-size Truck Two-Mode Hybrid Auxiliary Pump Diagnosis Owners of a Escalade, Silverado, Sierra, or Tahoe or Yukon, with the Two-Mode Hybrid option (RPO HP2) and 2ML70 transmission (RPO M99) may notice a driveability condition where the vehicle jerks or surges when the engine is in Auto Stop mode, as observed on the tachometer. The condition may include: A lull (clutch slipping) followed by a jerk (clutch grabbing) during acceleration from a stop with light throttle that occurs just before an engine restart, or A surge during deceleration below 15 mph with light to moderate braking that occurs after the tachometer drops to Auto Stop. Either of these conditions may be caused by an auxiliary transmission fluid pump or a slipping clutch within the transmission. Auxiliary pump part numbers ( ) and (2010) have been placed on restriction. If diagnostics lead to auxiliary transmission fluid pump replacement, contact TAC. PIP4751A in SI includes additional information for auxiliary pump diagnosis. Diagnosis The main hydraulic system of the Hybrid Two-Mode 2ML70 transmission primarily consists of a vane-type pump, two control valve body assemblies, converter housing and case. The pump maintains the working pressures needed to stroke the clutch pistons that apply or release the friction components. The hydraulic system also uses a secondary system consisting of an auxiliary pump attached to the bottom of the transmission. This is a gerotor-type pump that maintains working pressures when the engine is off in Auto Stop mode. TIP: A low State of Charge (SOC) of the 300V battery may cause a similar jerk Auto Stop on the tachometer or surge condition. An updated minimum SOC of 60% has been established since a recent Emerging Issues seminar discussing the auxiliary transmission pump was released. Let the vehicle sit for one hour and make sure the SOC is above 60% before beginning diagnosis of the auxiliary transmission fluid pump. During diagnosis, check for DTC P2797, Auxiliary Transmission Fluid Pump Performance, in the Hybrid Powertrain Control Module. If DTC P2797 is present, it is necessary to follow SI diagnostics for this code before proceeding with the repairs outlined in PIP4751A. Auxiliary transmission fluid pump Snap shot plot of stalled auxiliary pump TIP: If any DTC other than P2797 is present, follow the normal flow charts for the DTC in SI to identify the issue. After completing repairs for any set DTCs, take a snap shot while in Auto Stop mode with the vehicle in Drive and both the parking brake and service brakes applied to maintain zero vehicle speed. Next, slowly increase the throttle position to 25% until the ICE restarts (the Motor 2 torque command will exceed 100 Nm). Review the snap shot and graph Calc. Throttle Position, Motor 2 Torque Actual, Motor 2 Speed Actual, Aux. Trans. Fluid Pump Actual, and Engine RPM. In the accompanying snap shot plot, the auxiliary pump percentage is above zero, which means it s working electrically. Also, since the clutch has sufficient hydraulic force to keep Motor 2 from rotating, the auxiliary pump is operating mechanically. However, during operation of the pump, its percentage drops to near zero and the Motor 2 Speed increases. If the Motor 2 Speed exceeds 20 RPM and, at the same time, auxiliary pump percentage drops to near zero prior to the engine restart, the auxiliary pump has stalled. As a result of the drop in pressure to the clutch, Motor 2 is allowed to rotate. TIP: There may be audible indications of electric motor speed increases and clicking noises associated with the auxiliary pump stall. If the Motor 2 Speed stays below 20 RPM and the auxiliary pump percentage stays relatively steady until the engine restart, the pump is operating within normal parameters. When diagnosis reveals a stalling auxiliary pump, contact TAC for information on part replacement. Thanks to Steve Bunce and Keith Newbury 4 March 2010

5 Remote Start Seat Heating and Ventilation Some Global A architecture vehicles (2010 Camaro, LaCrosse, SRX, Equinox, Terrain) allow the driver to configure the heated and ventilated seats (if equipped) to turn on once a remote start is commanded. TIP: Refer to the Vehicle Person - alization Climate and Air Quality menu settings using the audio system controls to turn the remote start heated and vented seats feature on/off. The heated seats will only operate if the outside air temperature is below 50 F (10 C) as measured by the outside air temperature sensor. Seat ventilation will only operate if the outside air temperature is above 80 F (27 C). When seat heating is commanded, the heating level will be set to the High setting. On some vehicles, the LED display for the heating or ventilation level will not be illuminated during remote start operation. When the key is inserted in the ignition and turned to the On position, the heated seats will automatically turn off. If heated seat operation is desired after the remote start, the heated seat will need to be activated manually by the occupant. Be aware that during remote start heated seat operation, since there is no occupant in the seat, the occupant may feel little or no difference in the temperature of the seat. This condition is due to little heat transfer to the seat cover since there is no weight on the cushion. With remote start still active, once the seat is occupied and the seat cover is pressed against the heater element, heat will begin to transfer more rapidly to the seat cover. Thanks to Paul Gallo Service Consultant Information Battery Cable Connections The 2010 Camaro may have an intermittent no crank or dead battery condition. Inspect the battery cable connections in the Underhood Battery Cable Junction Block located near the left front strut tower and also at the UBEC for a poor connection. There may be signs of arcing on the terminal ends. Clean the terminals as required and reinstall the fastener. Underhood Battery Cable Junction Block location Underhood Battery Cable Junction Block connection Full-size Truck PPS Re-zero Procedure On the Escalade, Escalade EXT, Escalade ESV, Avalanche, Suburban, Silverado, Tahoe, Sierra, Yukon, Yukon Denali, Yukon XL, and Yukon Denali XL, the Passenger Presence System (PPS) re-zero procedure is not required. TIP: Tahoe Hybrid and Yukon Hybrid only (NOT Denali or XL Models) are the only full-size truck models that require the re-zero procedure. Starting in 2009 on the full-size pickup and utility models, the PPS features a new design that does not require it to be re-zeroed using the Tech 2. The re-zero procedure updated the empty seat reference values stored in the ECU. The re-zero procedure has been removed from the Tech 2 menu for these models that do not require a re-zero. Service Information is being updated. The Tech 2 looks at the GM part number in the PPS Module and determines if a re-zero process is needed. If a re-zero is needed, then the option will be available on the Tech 2 menu. If no re-zero function is listed, it s not necessary to perform the re-zero procedure. Thanks to James Will Service Replacement Headlamp If a service replacement headlamp for the 2010 SRX is received with a fractured plastic tab at the location shown, it is not necessary to return the part to Service Parts Operations. Damage to the headlamp retaining tab may have occurred during shipping. Do not return the part, this tab is used for production purposes only and is not required for service. The lamp housing can be modified before installation. If the tab is broken, use a hack saw and remove the remaining plastic retaining tab by cutting across both legs of the tab as illustrated by the dashed line. Remove the remaining plastic retaining tab March

6 Skipping Audio Playback from HDD Owners of a 2010 LaCrosse, SRX, Equinox or Terrain equipped with the navigation audio system may experience skipping audio (i.e. approximately 1-2 seconds of intermittent muting) or the song may not fully record (i.e. only plays a few seconds of a song that is several minutes long) when listening to songs from the HDD (Hard Disk Drive). This condition only occurs after saving the song to the HDD from a CD and playing it back from the HDD. The song may appear to play fine from the CD These conditions may be caused by an unclean CD. Fingerprints or small scratches on the disc may cause poor quality playback when a song is recorded to the HDD from a CD because different error correction/buffering is used during playback than during recording. Skipping audio playback of this type is not a fault of the radio silverbox and parts should not be replaced. Follow the directions in the Navigation Owner Manual or vehicle Owner Manual to properly clean the disc. If the disc is not able to be cleaned due to excessive scratches, an alternative method of loading the songs would be for the owner to make MP3 files of the songs on the disc, copy the files to a USB flash drive, and then record to the HDD from the USB port. Universal Garage Door Opener Connection The Universal Home Remote System or Universal Garage Door Opener (UGDO) on some 2010 Camaro models may not function properly due to a connection that is not fully seated at the UGDO transmitter module. Verify power to the module Ensure the tie strap is positioned away from the OHC Locator (A). by pressing any UGDO button and check that the LED illuminates. If the LED does not illuminate, remove the overhead console and check for battery voltage at the UGDO connector. If there is power at the UGDO connector, disconnect and The tie strap should be positioned behind the screw (B). reconnect the UGDO connector and secure with a tie strap. TIP: For proper clearance, be sure the tie strap is positioned away from the overhead console locator (A) and behind the screw (B) as shown. Verify LED operation by pressing any UGDO button and reassemble the overhead console. Intermittent Electrical Conditions In rare instances, various intermittent or hard-toduplicate electrical conditions may be found on some 2010 SRX models. The conditions may include any of the following systems: ABS/ traction control, adjustable pedals, brake fluid level, DVD/entertainment, engine coolant level, headlamp leveling actuators, heated mirrors, horn, IPC, rear defroster, steering wheel controls, turn signals, and windshield wipers/washers. There may be DTCs U0121, U0125 and/or U0126 stored. Various DIC messages also may be displayed. A loss of communication with one or more control modules may be found. These conditions may be very intermittent. If the published diagnostic procedures do not lead to the cause of the specific condition, inspect for proper electrical connection on all grounds related to the system being diagnosed. Poor electrical contact may be found at G131 and G201. The fastener may be tight, but the ground may still have poor electrical contact. Clean the related ground contacts and properly torque the fastener. Fuel Line Bracket Rattle On some Escalade, Escalade EXT, Escalade ESV, Avalanche, Silverado, Suburban, Tahoe, Sierra, Sierra Denali, Yukon, Yukon Denali, Yukon XL, and Yukon Denali XL models, a buzz or rattle type noise during light acceleration around RPM may be heard. The noise may sound like it is coming from behind the instrument panel. The buzz or rattle type noise may be caused by the fuel line bracket, above the transmission, contacting the floor pan. Reposition the fuel line bracket down away from the floor pan. Thanks to James Will 6 March 2010

7 Engine or Crankshaft Installation GM TechLink is a monthly magazine for all GM retail technicians and service consultants providing timely information to help increase know - ledge about GM products and improve the performance of the service department. Publisher: Thomas J. Arnold GM Service and Parts Operations / Thomas.Arnold@GM.com Editor: Lisa G. Scott GM Service and Parts Operations / Lisa.G.Scott@GM.com Technical Editor: Mark Spencer / mspencer@gpworldwide.com Production Manager: Marie Meredith Desktop Publishing: 5by5 Design LLC / dkelly@5by5dzign.com FAX number: Write to: * TechLink PO Box 500 Troy, MI GM TechLink on the Web: : GM GlobalConnect General Motors service tips are intended for use by professional technicians, not a do-it-yourselfer. T hey are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information. Inclusion in this publication is not necessarily an endorsement of the individual or the company. Copyright 2010 General Motors Company All rights reserved. When installing an engine or replacing a crankshaft on a LaCrosse, Allure (Canada Only), CTS, SRX, STS, G6; Enclave, Acadia, AURA, OUTLOOK; G8, Torrent; Equinox, Malibu, Camaro, VUE; Traverse; 2010 LaCrosse, CTS, CTS Wagon with 2.8L or 3.6L High Feature V6 Engine (VINs D, T, V, 7; RPOs LP1, LLT, LY7), the keyway on the replacement may be different from the original. Also, other engine components may be different and need to be used from the original engine. Original component with a keyway slot Repeat Poor A/C Performance Slosh Noise from Rear of Vehicle A sloshing noise while stopping may be heard on some 2010 Camaro models. The source of the noise may be from the fuel tank or the exhaust muffler at the rear of the car. To confirm if the noise is coming from the fuel tank, add or remove three gallons of fuel in the fuel tank and retest. If the noise is gone after changing the Replacement component with a round hole If the original has a keyway slot and the replacement has a round hole, use round pin part number in the crankshaft and then install the harmonic balancer. Install a new bolt and torque it properly. The harmonic balancer will not need to be changed. Be sure to follow all instructions included with the engine pertaining to the oil pan, front cover, flexplate, and other components. Thanks to Ronald Mitchell The owner of a 2010 Camaro may comment of repeat poor performance of the air conditioning system. Previously, the compressor may have been replaced for a broken compressor shaft. In addition, there may be signs of overheating, such as labels on the compressor being bubbled. If diagnosis leads to replacement of the A/C compressor for an overheating condition or broken shaft, check the Repair History. If the compressor has been replaced in the past for similar reasons, perform these additional steps in order to properly complete the repair. 1. Replace the compressor and the receiver/dehydrator 2. Flush the condenser and evaporator 3. Verify through Repair History that the HVAC (ECC) module has had the latest calibrations installed fuel level, then this is a normal operating condition. No repairs are needed. The noise is considered normal for that level of fuel in the tank. If the noise is present at all fuel levels, inspect for a blocked drain hole in the mufflers. Use an awl or small pick to clear the drain hole. March

8 Car Issues Fix It Right the First Time Model Year(s) Vehicle Line(s) / Condition Do This Don t Do This Reference Information / Bulletin Acadia, AURA, Avalanche, Cobalt, DTS, Enclave, Escalades, G5, G6, G8, H2, Impala, Malibu, OUTLOOK, Sierra, Silverado, SKY, Solstice, Tahoe, Torrent, Traverse, VUE, Yukons GM Accessory 2- way remote start transmitter battery Ensure that the transmitter is not in second vehicle mode and the battery is not dead Do not replace the battery if it is less than five months old or replace a transmitter because it is set for the wrong vehicle A Astra Chirp noise from accessory drive belt with A/C compressor on Replace the generator pulley Do not replace the generator or drive belt CTS, CTS-V, SRX, STS Shifter binds, ignition key sticks, shift to Park message, dead battery Adjust the shift linkage Do not replace the shifter without verifying the shift linkage is correctly adjusted C Aveo Poor acceleration, throttle body frozen shut in extremely low temperatures Install the PCV valve kit and reprogram the ECM Do not perform on inventory vehicles or replace the throttle body B Aveo, G3 HVAC blower motor inoperative, blower motor operates on high speed only Replace both the blower motor and the resistor Do not replace only a blower motor or only a resistor Allure, Camaro, Equinox, G8, LaCrosse, Terrain Key cutting procedure for obtaining replacement key Obtain the correct key code Do not use a four-digit key code C G8 Vibration in steering wheel, moan noise at highway speeds Replace the engine mounts, propshaft, balance wheel/tire assemblies or correct the brake rotor runout Do not replace the tires before completing the root cause All Vehicles Refinishing aluminum wheels Only cosmetic refinishing of the wheel s coatings, using recommended procedures is allowed Do not attempt any repairs that involve welding, bending, straightening or re-machining of the wheel D Cobalt, HHR, SKY, Solstice Ticking noise heard during cold start Compare to other vehicles to ensure the noise is not excessive Do not replace the high pressure fuel pump F 2010 Camaro Accessory drive moan noise when A/C compressor cycles Replace the accessory drive belt Do not replace the pulley A Truck Issues Fix It Right the First Time Model Year(s) Vehicle Line(s) / Condition Do This Don t Do This Reference Information / Bulletin Acadia, AURA, Enclave, Equinox, G6, Malibu, OUTLOOK, Torrent, Traverse, VUE No Reverse, 3rd or 5th gear Disassemble the transmission to clean debris generated by the broken wave plate. Replace the pump fluid filter and the control solenoid filter plate Do not make repairs without cleaning the transmission and replacing the pump fluid filter and the control solenoid filter plate A 2010 All Vehicles Exterior paint codes Include the correct paint WA# when ordering paint Do not order paint without including the WA# Canyon, Cobalt, Colorado, Sierra, Silverado Intermittent Check Engine light on, DTC P0442, P0446, P0451, P0452, P0453, P0454 or P0455 Install a fuel tank pressure sensor cover Do not replace the fuel tank pressure sensor Sierra, Silverado Fluid leak from transmission vent during cold weather Install new vent assembly with extension hose Do not drill a hole in the transmission filler tube or replace the transmission Equinox, Torrent Liftgate hard to open in cold weather In extreme cold weather (below 0 C/32 F), replace both liftgate struts with new parts Do not use the old strut part number A Sierra, Silverado Snow ingestion into air cleaner element, Engine Power Reduced message, DTC P0101 Install the winter grille opening cover Do not modify the air filter box A Avalanche, Escalades, Sierra, Silverado, Tahoe, Yukons Correct front axle vent hose routing Correctly route the axle vent line Do not leave the axle vent line routed incorrectly A Service Know-How D Emerging Issues March 11, 2010 To view Emerging Issues seminars: Log in to select Service Know-How/TECHAssist from the menu, select Emerging Issues, and then Searchable Streaming Video to choose the current Emerging Issues seminar or past programs. 8 March 2010