Archive for July 2016

New Electronic Transmission Range Select Shift-by-Wire System

Selecting a gear on the Aisin AF50-8 8-speed automatic transmission (RPO MRC) in the new 2017 XT5 and LaCrosse takes only a flick of the wrist. These two models feature the first application of Electronic Precision Shift, which is a shift-by-wire system. Additional future models also will feature this system, which is controlled by various control modules both internal and external to the transmission.


The Electronic Transmission Range Select (ETRS) lever (Fig. 1) enables the transmission range to be selected by electronic control rather than by mechanical means. There is not a physical link, cable or linkage between the shifter and transmission.


F01 AutoTrans Shift Lever

Fig. 1


ETRS Shift Lever


The automatic transmission shift pattern — Park, Reverse, Neutral, Drive, and Manual positions — is displayed on top of the shift lever. The lever contains sensors that indicate the desired transmission range. The selected gear position illuminates in red on the shift lever. The shift lever always starts in a center position, represented by a dot on the shift pattern. After shifting, it returns to the center position.


A non-contact type gear shift position sensor has been integrated in the Transmission Control Module (TCM). The sensor detects shift position, based on driver input using the shift lever, by using the Hall Effect, which outputs specified voltage according to the shift position. The magnet position in the sensor changes when moving the shift lever, enabling the Hall integrated circuit to convert magnetic field strength into an electrical signal according to the shift position.


The ETRS shift lever assembly includes:

• Shift Interlock Button – Located on the side of the shift lever, it has two sensors that are both inputs to the Chassis Control Module.

• Park Button – Located on top of the shift lever, it has two sensors that are both inputs to the Chassis Control Module.

• Two Dimensional Shift Lever –The shift lever position is determined by two internal sensors that each transmit an X and Y coordinate signal. All four signal circuits are inputs to the Chassis Control Module. The shift lever is designed so any single fault at the shifter can be isolated and error corrected by the Chassis Control Module.

• Transmission Shift Lever Position Indicator – The LED display on the face of the shift lever indicates the transmission’s actual gear position. It displays R (Reverse), N (Neutral), P (Park), D (Drive), and M (Manual).


Gear Selection


Park – To shift into Park, press the Park button on top of the shift lever. To shift out of Park, with the ignition on and the brake pedal applied, press the Shift Interlock button on the side of the shift lever and move the lever to the desired gear.


Reverse – Press the Shift Interlock button on the side of the shift lever and move the lever forward and then left to shift into Reverse.


Neutral – Move and hold the lever forward to shift into Neutral. The transmission will automatically shift into Park after an extended period in Neutral. To exit the vehicle with the transmission in Neutral, such as when at a full-service car wash: press the brake pedal, open the driver’s door, and then shift to Neutral.


Drive – Move the lever rearward to shift into Drive.


Manual – While in Drive, move the lever rearward to activate manual mode. Use the steering wheel paddles to shift. Press rearward on the shift lever again to return to Drive.


The Chassis Control Module (CCM) monitors the position of the shift lever and communicates the information to the Transmission Range Control Module (TRCM), which then turns the gear selector shaft using a motor connected to the range selector shaft. The TRCM communicates on high-speed GMLAN and the Chassis Expansion Bus.


The Park/Neutral Position (PNP) switch is part of the TCM assembly. The TCM provides a ground to the ECM in Park and Neutral. The PNP switch provides a range signal (permission to crank) to the ECM to enable the engine to start.


All Electronic Transmission Range Selector and Transmission Range Control Module DTCs will set in the Chassis Control Module.


When a fault is detected in the Electronic Transmission Range Select system, the Driver Information Center (DIC) on the instrument cluster will display the message “Service Transmission Now, Unable to Shift Soon” along with a 10 second chime. The driver must acknowledge the message to display other information on the DIC. The message and chime will continue to occur until 50 trips are reached with the fault present. At that point, the transmission will not be allowed to shift out of Park.


When the “Service Shifter See Owner’s Manual” message is displayed on the DIC, the shift lever requires service. If the vehicle is automatically shifting into Park, check that the Park button is not stuck by going through the shifter electrical diagnostics in the appropriate Service Information. To operate the vehicle, hold the shift lever in the desired gear, Reverse or Drive, until vehicle speed exceeds 10 mph (15 km/h), and then release the shift lever.


ETRS Components


The ETRS components include:

• S3 Transmission Shift Lever • K38 Chassis Control Module • K173 Transmission Range Control Module • Backup Park Lock, located within the K173 Transmission Range Control Module • P2 Transmission Shift Lever Position Indicator, located within the S3 Transmission Shift Lever • K71 Transmission Control Module


The TCM is mounted directly on top of the transmission. (Fig. 2) The selector lever and transmission range sensor is integrated in the control module. The TCM is mounted so that the selector lever shaft goes through the control module. The shift lever position is calibrated with a scan tool; there is no mechanical adjustment.


F02 8-speed trans R

Fig 2


An external 16-terminal connector connects to the vehicle’s electrical system. Underneath the control module is another connector (33-terminal) that connects directly to the transmission. The TCM makes contact with all the transmission solenoids and sensors here.


TIP: Magnetic fields from magnets and high-current cables, such as starter cables and cables to auxiliary equipment, can interfere with the gear position sensor. A rule of thumb is a maximum 1A per mm in distance from the control module. Therefore, a starter cable carrying a current of 200A must be kept at least 20 cm away from the control module.


The TCM has a microprocessor with clock, RAM memory and a programmable ROM. Adaptive values are saved in the non-volatile memory (ROM). When the transmission is repaired or replaced, these values must be zeroed using a scan tool. When a TCM is replaced, the adaptive values do not transfer from the old TCM to the new TCM.



Default to Park


The Backup Park Lock function, also known as Default to Park, is electrically isolated from the TRCM, and forces the transmission manual shaft to the Park position under specified conditions. Under these conditions, the vehicle is put in Latent Fault Mode. The Backup Park Lock communicates with the Chassis Control Module via a Local Interconnect Network (LIN).


Critical Fault Mode


When a fault is detected in the Electronic Transmission Range Select system and the requested gear position or actual gear position cannot be determined, the vehicle will remain in the current commanded gear position until the vehicle speed is below 1 mph (3 kph).


In order to lower vehicle speed, the EBCM will engage braking. When vehicle speed is below 1 mph (3 kph), the electronic park brake and backup park lock (also known as Default to Park) will engage. The electronic park brake will not disengage until the condition is corrected and all related DTCs are in History.


Learn Procedures after Service


The Gear Selector -N- Position Learn procedure is required when the TCM, ECM, Transmission Shift Lever, or transmission assembly has been repaired, replaced, removed, or serviced. Perform the procedure using the scan tool learn/reset function.


The Learned Values Reset procedure is required when the transmission assembly, torque converter, TCM, control valve body or Transmission Input Shaft Speed Sensor has been repaired, replaced, removed, or serviced.


– Thanks to Salvatore Canale

Check Out the Service Information Technician Forum

A discussion with other technicians about diagnostic and repair information, GM service applications and other topics is a click away on the Service Information (SI) Technician Forum at A one-time registration is required.


The forum also can be accessed through GlobalConnect. Click the App Center link to view all apps, and then click the Technician Forum icon under Service.


Designed to promote communication among the GM technician community, the SI forum (Fig. 3) offers discussions on repair information covering all GM brands. Polls on a variety of GM service initiatives and common questions about service applications are a few of the other things that can be found on the forum. The forums are monitored by various subject matter experts who can assist with concerns and unanswered questions.


F03 forum image

Fig. 3


Forum Categories


The forum is organized in categories that range from specific diagnostic and repair information to general comments on daily life in the service department. The topics cover diagnostic and repair information for individual vehicle lines; general technical information covering training, infotainment systems, OnStar, collision repair and parts; tools; management topics; service applications and computer issues; and more.


Forum categories include:


Diagnostic and Repair Information – Covers repairs on Buick, Cadillac, Chevrolet, Chevy Truck, Chevrolet Volt, Medium Duty Trucks, GMC, Hummer, Oldsmobile, Pontiac, Saturn, and Saab models.


General Technical – Includes topics on all service manual sections, training and testing, digital technical pictures, OnStar, collision repair, and parts.


Tools – Features topics on scan tools, general tools, and the CH-51450 Oscilloscope Diagnostic Kit.


Service Manager – Discussions on management insight, customer satisfaction, and warranty issues.


Computers – Covers the Service Information, Data Bus Diagnostic Tool, Techline Information Systems, GDS 2, TechLink, PC software, PC operating systems, and PC hardware.


General Community – Open forum on non-technical discussions.


Share your experiences with fellow technicians. Visit the SI forum at


– Thanks to Lisa Scott

2016 Technician Satisfaction Survey Coming Soon

The annual automotive industry Technician Satisfaction Survey will soon be taking place and technicians at all dealerships are encouraged to participate. Sponsored by GM and other automotive manufacturers, this year’s survey focuses on technician recruitment and retention in the dealership.


2016 Survey: September 19 – October 14


All GM Service Technicians, Technician Apprentices, and Maintenance Inspection Technicians (MIT) profiled in the Center of Learning will receive emails announcing the survey and a link to the survey. The survey will be available from Monday, September 19, to Friday, October 14.


The short survey shouldn’t take more than 15 minutes. The valuable feedback received from the survey results will be used to help GM support dealerships in their efforts to recruit and retain technicians.


Feedback from previous surveys has helped GM provide support for dealership technicians in a number of ways. Here are a few examples from recent surveys.


Improve communication between technicians and service consultants to explain the operation of infotainment systems – Several technical training courses have been updated that help in understanding the operation of infotainment systems. In addition, content in the monthly Emerging Issues Service Know-How Seminars (TAC Talk in Canada) that is useful to service consultants is identified so they can relay that information to customers. New Model Features (NMF) training content also is now available to service consultants.


Improve service technician recognition – GM has completely revamped the Mark Of Excellence Service Technician Performance Recognition Program in the U.S. for 2016. (Fig. 4) Technicians now benefit from new weighted rankings. Each technician is ranked based on points earned and can win apparel, gift cards, a toolbox medallion, earnPOWER points, tool gift cards, and zone banquet and national travel awards. GM Canada supports technician recognition through the Technicians Guild Program, which focuses on technical education, professional development and customer service satisfaction.



Fig. 4


Introduce new and innovative ways for technicians to learn (U.S. only) – Interactive video, a new training media, has been introduced that leverages the engaging production qualities of traditional video and adds user-involvement technology. The first application of interactive video is the High Voltage Depower Tool Usage course (18420.17W). (Fig. 5) Performance Support Objects also have been launched, which take the form of video or text, and contain key points derived from technical training courses that reinforce training content.


F05 interactive video

Fig. 5


Create job roles for the skill level of Light Maintenance and include these job roles in the survey pool (U.S. only) –Maintenance Inspection Technician (MIT) and Technician Apprentice job roles have been created in the Learning Management System. These job roles are included in this year’s survey.


GM would like to thank all dealership technicians for your dedication and valuable feedback. Look for the survey link in your email soon.


– Thanks to Diana Sancya, Chris Wallace, George Kalso and Bernie Pyra



UPDATE: Blu-ray Discs Not Playing

Certain Universal Studios Blu-ray discs released after October 2015 may not start playing when the Play icon is pressed on some 2013-2016 SRX, XTS; 2014-2015 LaCrosse; and 2015-2016 Escalade, Silverado, Tahoe, Sierra and Yukon models equipped with the Rear Seat Entertainment system (RPO UWG, UWJ or U42). This condition does not affect accessory headrest-mounted DVD players.


When users select “Play” to begin playing an affected Blu-ray disc, the disc menu disappears and the menu background animation continues to loop.


The Blu-ray specification is large and allows for a lot of flexibility in the way users interact with the video content. Some studios have recently changed the way their menus are laid out to take advantage of the previously unused functionality, resulting in the Play menu error.


Software Update CD


A software update is available to correct this condition. Although this module is normally programmed via USB and calibrated via GM LAN, this particular portion of the module’s firmware requires that a CD be inserted into the module for an update.


The CD, part number V-IN2016-CD, began being shipped to dealerships in August 2016. Currently, shipping of the CDs continues, so not all dealerships have received a CD yet.


Check Software Version Number


To determine if the module needs to be updated, check the software version number. Turn on the Rear Seat Entertainment System, press the Menu button on the remote control and select Software Information, and then select Version and Other Micros. If F/E = 03/12/14 and B/E = 06/01/16, no update is necessary.


System Update


If an update is necessary, connect the vehicle to the Midtronics® PSC 550 Battery Maintainer or a similar programming support tool to ensure a proper battery charge.


If the vehicle is equipped with two screen displays both must be on. With a single overhead display, the screen source must be on Source #1. Select remote button “1” or “2” to switch between sources. With dual overhead displays, the 2nd-row screen will be Source #1 and the 3rd-row screen will be Source #2.


In vehicles with seatback displays, the left (driver) display is Source #1 and can be controlled by selecting remote button “1.” The right (passenger) display is Source #2 and can be controlled by selecting remote button “2.”


Select a tuner source (AM, FM, or XM) on both rear displays (if equipped) and the front screen. For the rear displays, press the Radio button on the remote control and select AM, FM, or XM using the left/right buttons on the remote control. Be sure to do this for both rear displays (if equipped). The front center stack screen must be changed a tuner source (AM, FM, or XM) using the infotainment controls.


Remove any media in the player, located in the instrument panel or in the glove box, and insert the update CD. A popup message will appear on the rear display(s). Select OK by highlighting the button with the remote control and pressing Enter. (Fig. 6) After a short time, the update CD will automatically eject. Remove the CD from the player.


F06 CD 1

Fig. 6


Next, a message stating “Please insert Update disc” will appear on the rear display(s). Re-insert the same update CD. Do not select Cancel. (Fig. 7)


F07 CD 2

Fig. 7


Wait for the files to be copied. It should take about 20 minutes. The system will stay on the first update screen for about 5 minutes after the update CD has been re-inserted. The system will then display “updating back-end firmware” with a progress percentage. Once 100% has been reached, the CD will eject and can be removed. During the update process, one of the rear displays may stop displaying content.


TIP: Do not turn the power off or use the remote control after the update process has started. Do not touch the system until the update CD ejects automatically.


Once the CD is ejected, the update process will continue for a few more minutes. The progress display will reset to 0% and “updating front-end firmware” will be displayed.


When the update process has finished, an “Update is complete” message will appear on the rear display(s). Select OK with the remote control and the system will restart automatically. (Fig. 8)


F08 CD 3

Fig. 8


After the player restarts, check the software version in the Other Micros section. Verify that the updated software is F/E = 03/12/14 and B/E = 06/01/16.


Refer to Bulletin 16-NA-205 for additional information and for instructions on ordering a replacement CD if needed.


– Thanks to Dave Gumpert

Engine Wiring Harness Chafing Conditions

A number of conditions regarding engine performance and air conditioning operation on some 2016 Colorado and Canyon models may be due to the engine wiring harness rubbing on other components. These conditions may include the air conditioning blowing hot air, a fluctuating engine oil pressure gauge, an engine no start or misfire, and several illuminated warning lamps or Driver Information Center (DIC) messages.


Complete the diagnostic instructions in the appropriate Service Information for any symptoms or DTCs found. If the diagnosis does not lead to a resolution, check for chafing of the engine wiring harness in the following areas, perform any necessary wiring repairs and reroute the harness.


• Air conditioning (A/C) compressor, A/C compressor suction and discharge line manifold, A/C line and A/C compressor clutch (Fig. 9)


A wiring harness concern in these areas may cause:

• The Check Engine light to illuminate and the engine to run rough or not start. • The 4WD warning lamp or StabiliTrak warning lamp to illuminate. • The oil pressure gauge to read erratically or read no oil pressure. • The A/C to not cool. • An open fuse in the Underhood Bussed Electrical Center (EBEC).


F09 engine harness 1

Fig. 9

• Serpentine belt near the fan clutch wiring harness support bracket (Fig. 10)


The support bracket may be out position and allow the harness to run on the belt, which may cause:

• An engine crank, no start condition or the engine to run rough or misfire. • The Check Engine light or other warning lamps to illuminate, such as the 4WD warning lamp or StabiliTrak warning lamp. • The A/C to not cool


F10 engine harness 2

Fig. 10


• Exhaust heat shield near the right rear of the engine (refer to Bulletin #16-NA-081) (Fig. 11)


A wiring harness concern in this area may cause:

• The 4WD warning lamp or StabiliTrak warning lamp to illuminate. • The Check Engine light to illuminate. • A Reduced Power message on the DIC. • An open fuse in the EBEC.


F11 engine harness 3

Fig. 11


• Transmission bell housing bolt/stud (Fig. 12)


A wiring harness concern in this area may cause:

• The 4WD warning lamp or StabiliTrak warning lamp to illuminate. • The Check Engine light to illuminate.


F12 engine harness 4

Fig. 12


• Coolant pipe and clamp tabs between the engine and cowl (Fig. 13)


A wiring harness concern in this area may cause:

• The 4WD warning lamp or StabiliTrak warning lamp to illuminate. • The Check Engine light to illuminate.


F13 engine harness 5

Fig. 13


• Brake fluid level switch (Fig. 14)


A wiring harness concern in this area may cause:

• The Check Engine light and service brake lamp to illuminate. • A Low Brake Fluid message on the DIC.


F14 engine harness 6 Fig. 14


• Transfer case encoder motor (Fig. 15)


A wiring harness concern in this area may cause:

• The Check Engine light or other warning lamps to illuminate.


F15 engine harness 7

Fig. 15


– Thanks to John Stempnik

Crankshaft Rear Oil Seal Leak

Some 2016-2017 Encore and Cruze models equipped with the 1.4L engine (RPO LE2) and 2016-2017 Malibu and Volt models equipped with the 1.5L engine (RPO LFV, L3A) may have a leak at the crankshaft rear oil seal. Abnormal crankcase pressures caused by a restriction in the induction system may lead to an oil leak at the crankshaft rear oil seal.


In order to determine the root cause of the engine oil leak, it’s necessary to test for excessively negative or positive crankcase pressures using the Evaporative Emissions System Tester (EEST).


The EEST connects at the engine oil dipstick port using the J-41413-300 hose adapter. (Fig. 16) The connection must be made with the engine off. The engine is then started and the pressure reading is recorded. Normal crankcase pressure readings for the 1.4L engine and the 1.5L engine are between -1 and -5 inches of water in Park at hot idle. (Fig. 17)


F16 crankcase 1

Fig. 16


F17 crankcase 2

Fig. 17


If crankcase pressure is in the proper range, follow the appropriate Service Information diagnostics for engine oil leaks.


If the crankcase pressure is excessively positive, above 0 inches of water, there is a positive crankcase pressure condition. Record cylinder leakage readings and check for improper camshaft cover operation.


If the crankcase pressure is excessively negative, below -16 inches of water, there is a negative crankcase pressure condition. Inspect for any air induction restrictions in the front air intake duct to air cleaner housing or in the air cleaner housing, such as water intrusion, a kinked PCV tube or any air induction system modifications.


In addition, inspect the air cleaner outlet duct for a blocked PCV fresh air port. (Fig. 18) If the port is not blocked, replace the camshaft cover assembly and retest for proper crankcase pressure.


F18 crankcase 3

Fig. 18

– Thanks to Raymond Haglund

Engineering Information Bulletins and Part Restrictions

Restrictions 08242016 1Restrictions 08242016 2Restrictions 08242016 3Restrictions 08242016 4Restrictions 08242016 5

Service Know-How

10216.08V – Emerging Issues

August 11, 2016


The latest service topics from Brand Quality and Engineering are reviewed, including information on the integrated trailer brake system on full-size trucks and how to remove the shift knob from a 2016-2017 Cruze with a manual transmission.


F19 EI image

Fig. 19


To view Emerging Issues seminars:

  • Log in to
  • Select Resources > Video on Demand > GM STC > Search Videos; or
  • Select Catalog to search for the course number, and then select View > Take or Continue Course

Engine Concerns Resulting from Improper Service

Following the recommended vehicle maintenance schedule is critical to proper engine operation over the life of a vehicle. Performing the required maintenance procedures on all GM vehicles reduces the possibility of engine oil sludge build-up, contamination and/or any other conditions that may result in poor engine performance and internal engine damage.


Vehicles that have a lack of scheduled maintenance, have improper service performed, or have aftermarket calibrations installed are not covered under the new vehicle warranty.


Scheduled Maintenance


There are a number of conditions that will be evident if a vehicle’s recommended maintenance has not been followed.


Oil Filter – An oil filter may be blocked by debris and oil sludge if regular maintenance is neglected. On vehicles equipped with an oil filter cartridge, inspect the cap for sludge. (Fig. 1, #1) Also check the oil filter pleats (Fig. 1, #2) for heavy debris or sludge as well as any holes, tears or signs of improper installation. Check the cap for a missing seal too. (Fig. 1, #3)


F01 maintenance 1

Fig. 1


Oil Pan – Improper maintenance can lead to sludge build-up in the bottom of the oil pan. Sludge or debris in the bottom of the pan (Fig. 2, #1) may block the pick-up tube screen. Some light debris in the oil pump pick-up tube screen should be considered normal. (Fig. 2, #2) Use your judgement to determine what is or what is not considered normal wear.


F02 maintenance 2

Fig. 2


Valve Cover and Camshaft – The valve covers may be blocked at the engine breather, vacuum or oil supply and return ports if regular maintenance has not been performed. Sludge may be seen on the camshaft caps and camshaft. (Fig. 3, #1 and #2) Low oil pressure or a loss of pressure may lead to damage, such as scratches or gouges on the journals or lobes of the camshaft. (Fig. 3, #3) A lack of oil from lack of maintenance also may create a lifter tappet ticking noise. Check for sludge build-up on the camshaft position actuator solenoids (Fig. 4, #2) and debris on the solenoid screen. (Fig. 4, #1)


F03 maintenance 3

Fig. 3

F04 maintenance 4

Fig. 4


Improper Service


The improper service of a vehicle may result in poor engine performance. Also make sure components are properly installed when performing maintenance procedures.


Air Filter – Improper installation of the air filter in the air filter housing or the use of an aftermarket air filter can allow foreign debris (Fig. 5, #2) to bypass the air filter or the air filter housing outlet ducts and enter the combustion chamber. As result, there may be damage to the piston and cylinder wall. (Fig. 5, #1)


F05 maintenance 5Fig. 5


Bearings – Main and rod bearing damage may be caused by foreign debris. Dust and debris on the crankshaft, crankshaft bearings, rods or rod bearings can cause the chrome finish of the journals to prematurely wear (Fig. 6, #1 and #2), increasing clearance and possibly causing low oil pressure or a knocking noise. Scratches on the journals also can lead to a loss of oil pressure.


F06 maintenance 6

Fig. 6


Aftermarket Calibrations


Engine damage may result from incorrect calibrations or other modifications made to the vehicle. Non-GM engine calibrations can be identified using the Tech 2 or GDS 2.


Pistons – Piston damage may be caused by a pre-detonation lean event. (Fig. 7, #1) Improper engine warm-up, such as from aftermarket cold air filters, can create excessive heat to the pistons and cause them to seize to the cold cylinder walls and crack the piston lands. (Fig. 7, #2)


F07 maintenance 7

Fig. 7


– Thanks to Tracy Lucas

MDI 2 Available through GM Tools and Equipment

The GM MDI 2 (Fig. 8) released earlier this year is the next generation Global Diagnostic Interface tool for both current and future GM vehicles. It’s a compact communication module with increased processing power and security that manages the transfer of data between a vehicle’s onboard network and a service technician’s PC.


F08 EL-52100_MDI_2_a

Fig. 8


Available through GM Tools and Equipment


The new MDI 2 is not an essential tool, so it has not been shipped automatically to all GM dealerships.


The GM MDI 2 kit (EL-52100) is available for purchase at the Special Service Tools website,, or by calling 1-800-GM-TOOLS. The tool comes with a two year supplier warranty.


Designed for the Future


The MDI 2 is the main diagnostic tool for GM models — including Global Architecture, or Global A, vehicles — and was designed to handle future vehicle protocols and architectures as well. It’s expected to be the diagnostic communication tool used in dealerships for many years to come, but it also is backward compatible, so it can be used to perform Pass-Thru programming on all vehicles built since 1996.


Current plans call for the original MDI, introduced in 2007, to continue to be supported. However, the MDI will not work on future Global B models.


The MDI 2 supports diagnostic applications — GDS 2, Data Bus Diagnostic Tool, and Tech2Win — as well as Pass-Thru programming applications — TIS2Web–SPS.


EL-52100 MDI 2 Kit


The MDI 2 connects to the vehicle via the J1962 connector using a DLC cable. Connection between the MDI 2 and the PC running the GDS 2 software can be accomplished via a standalone connection (USB), the dealership network (CAT5), or through a new Point-to-Point wireless Wi-Fi interface feature (a simple plug & play).


The EL-52100 MDI 2 kit (Fig. 9) includes:

• MDI 2 Unit

• SAE J1962 DLC Cable

• 10-ft. USB A to USB B Cable

• Ethernet Cable

• D-Link Wireless USB Adapters (Dongles) (Optional; for wireless connection)


F09 MDI 2 kit

Fig. 9

MDI Manager Software


The MDI Manager must be installed on the PC in order to configure, update and run the diagnostic applications. The MDI Manager software is used to set up the configuration of the MDI 2 and to update the firmware on the MDI 2. Visit the TIS2Web/Global TIS website to determine if an updated version of the MDI Manager software is available.


Dealerships considering new purchases should look into the MDI 2 for its many advantages. For more information, go to


– Thanks to Chris Henley and Kent Woiak

Proper Shipping of Hybrid Transmission Returns

A number of 5ET50 electric variable automatic transmissions (RPO MKE) from 2016-2017 Volt and Malibu Hybrid models recently returned to GM have been damaged during shipping due to improperly securing the transmission in the shipping cocoon.


There is a ratcheting strap in the cocoon that must be used to properly secure the transmission. The strap should be placed completely across the transmission; not on one corner or one side. (Fig. 10)


F10 return connector damage

Fig. 10


All electric variable transmissions are on part restriction and must be returned to GM if diagnosis leads to replacement. Components on restriction are returned in order to gather engineering feedback and perform root cause analysis of the failure. It’s critical to this endeavor that the transmissions are returned as they were on the vehicle. Many transmissions are put on a dynamometer for evaluation as well as installed in a vehicle prior to teardown. This evaluation cannot be accomplished if due care is not used to ensure that all components are properly secured and damage (Fig. 11) does not occur during return shipping.


F11 return strap

Fig. 11


As part of the restriction program, technicians are required to provide detailed customer comments, conditions, Diagnostic Trouble Codes (DTCs) and other useful information when calling the Technical Assistance Center. For example, freeze frame failure records should be captured along with DTCs. Any DTCs should not be cleared.


To ensure the replacement transmission gets to dealerships undamaged, a new “blue stripe” shipping container is now being used that includes an improved strap.


– Thanks to Keith Newbury

Inoperative Sunroof and Sunshade

The sunroof glass (RPO C3U) and sunshade may be inoperative on some 2016 CT6 (Fig. 12), Malibu (VIN Z) and 2017 LaCrosse and XT5 models. DTCs B3664 (Sunroof Position Select Switch High Signal Circuit), B369B (Sunroof Sunshade Position Select Switch Circuit), B369C (Sunroof Tilt Position Select Switch Circuit), U1517 (BCM Lost Communication with Sunroof Sunshade Motor Module) and/or U151B (BCM Lost Communication with Sunroof Control Module) may be set.


F12 sunroof

Fig. 12


Inspect the sunroof wiring harness for a loose connection by wiggling the harness (Fig. 13, B) while operating the sunroof motor. (Fig. 13, A) If the sunroof motor cuts off while wiggling the harness, replace the sunroof wiring jumper harness. If all sunroof motor functions work properly, continue with further diagnostics as outlined in the appropriate Service Information. Do not replace the sunroof motor or sunshade motor (Fig. 13, C) for this condition.


F13 sunroof motor

Fig. 13


If replacing the sunroof wiring jumper harness:

• Disable the SIR system.

• Lower the headliner from the rear up to the B-pillar. Only perform the steps in the headliner replacement procedure that will lower the headliner enough to gain access to the part.

• Disconnect the sunroof wiring jumper harness from the sunroof window motor to the headliner harness.

• Connect the new sunroof wiring jumper harness starting from the sunroof motor while re-clipping it to the headliner down to the headliner harness.


TIP: Do not change the wiring harness routing location. Correct harness routing is critical for proper air bag deployment.


In addition, if the sunroof motor and sunroof mechanism get out of sync, the sunroof may operate erratically. To re-synchronize the motor and sunroof mechanism, perform the Sunroof Motor/Actuator Initialization/Teach Process. If the process is not carried out completely, the sunroof may stop and reverse slightly when it gets to the location where it needs to push down the windscreen. Make sure to complete the process.


– Thanks to Dallas Walton and Blake Streling

Part Identification for Next Generation Infotainment Components

The applications of some next generation infotainment components used on 2013-2016 ATS, SRX, XTS; 2014-2016 Regal, LaCrosse, CTS, ELR, Corvette, Impala Silverado LD, Sierra LD; 2015-2016 Escalade models, Colorado, Silverado, Tahoe, Suburban, Canyon, Sierra, Yukon models; 2016 Envision, CT6, Camaro, Cruze, Malibu; 216-2017 Volt; and 2017 XT5 models may not be clear.


Dealership personnel should check that the correct infotainment components are ordered and replaced when making repairs to Integrated Center Stacks (ICS), OnStar modules, Human Machine Interface (HMI) modules, radios, and Driver Information Displays. For example, do not replace the ICS when it is actually the radio that requires replacement.


Refer to the following photos to help in identifying the correct parts.


Integrated Center Stack (ICS)


The ICS includes the display and radio control assembly, including the control knobs and buttons for all audio and HVAC functions and the information display. (Figs. 14, 15, 16)


F14 ICS 1

Fig. 14


F15 ICS 2

Fig. 15


F16 ICS 3

Fig. 16


OnStar (Telematics Communication Interface Control Module/Vehicle Communication Interface Module)


The VCIM (Fig. 17) is used to communicate data and voice signals over the national cellular network. The module may also have the ability to act as a Wireless Local Area Network (WLAN) Wi-Fi hotspot. It also two antenna inputs, a primary cellular signal and a combined GPS/secondary cellular signal.


Do not mistake the VCIM for the HMI.



Fig. 17


Human Machine Interface (HMI)


The HMI module (Fig. 18) is responsible for video for the infotainment display, Bluetooth, USB, memory card reader, and speech recognition functions.



Fig. 18




The radio (Fig. 19) is the Media Oriented Systems Transport (MOST) BUS master that is responsible for normal wake up and initialization of communication on the network. It communicates with other components and systems within the vehicle via GMLAN and is responsible for receiving all broadcast audio bands.


F19 Radio

Fig. 19


Driver Information Display


The Driver Information Display, used on the Corvette only, includes the touchscreen. (Fig. 20)


F20 display

Fig. 20


For additional information about the various infotainment components used on GM models, refer to #PIC6095B.


– Thanks to Ryan Dorland

Adding an RKE Transmitter without SPS

Adding a new Remote Keyless Entry transmitter, or key fob, to a vehicle can be done without using the Service Programming System (SPS). In the past, this quick learn procedure required that one previously learned transmitter must be present.


On 2017 XT5, Acadia and Volt models, two previously learned transmitters (Fig. 21) are required in order to perform the quick learn procedure. The transmitters should be placed in the cup holder.


F21 key fobs

Fig. 21


If two transmitters are not present, the procedure will not be completed and a Remote Learning Pending message will be displayed on the Driver Information Center. The quick learn procedure on these models cannot be performed without the correct number of transmitters. If only one learned transmitter is available, SPS must be used to add a new transmitter.


When using the quick learn procedure to add a transmitter without SPS, verify all mechanical keys operate correctly before beginning any programming procedures.


A total of eight transmitters can be learned to a single vehicle. The quick learn procedure only adds transmitters. It does not erase previously learned transmitters.


– Thanks to Christopher Crumb

Engineering Information Bulletins and Part Restrictions

Restrictions 07272016 1

Restrictions 07272016 2

Restrictions 07272016 3Restrictions 07272016 4

Restrictions 07272016 5

Service Know-How

A review of the latest service topics from Brand Quality and Engineering, including radio software updates and tips on adhesive parts installation and replacement, including moldings and emblems.


F22 EI image

Fig. 22


To view Emerging Issues seminars:

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