2003 TrailBlazer 4WD problems - how to get TSBs

Last week my TrailBlazer's 'Service 4WD' light came on, the transfer case indicator lights were all out, and the transfer case switch didn't work at all. I turned the car off for a minute and back on and still the same. So I went inside where I was parked and just decided to take it to the dealer on Monday. When I left to go home a couple hours later, everthing worked fine and has since. I noticed about 6 or 7 TSBs for the 2003 TB's listed with the NHTSA, 4 of the descriptions sound just like my problem. Unfortunately I wasn't able to throw an OBD-II reader on it before the code went away. Can anyone get me these TSBs or tell me how I can?

The dealer says I need to come in and have my system flashed with updated firmware.

Here is a list of some I think I may be experiencing:

02-04-21-006/A/B/C/D keep showing up when I look around.

From NHTSA:

01410 - POOR PERFORMANCE FROM A STOP IN 2WD, AUTO OR 4WD HI. 2003, 2003 CADILLAC EXT ALSO INCLUDED. *TT 030421005 - SERVICE 4WD LIGHT ON, 4WD INOPERATIVE, DIAGNOSTIC TROUBLE CODES C0300 AND/OR C0305 SET. *TT

From AllData:

02-04-21-006D - AWD/4WD System - Lamps/System Inoperative 03-04-21-005 - Transfer Case Control Module - 4WD Lamp ON/DTC'S Set 02-04-21-002A - Indicator ON/DTC B2725 Set

From Edmunds:

01459 - SERVICE 4WD LIGHT ON NO CODES BESIDES U1000 CODES. *TT

Regards,

-- Mike

Reply to
Mike Brancato
Loading thread data ...

Your dealer is correct. There have already been about 2-3 software updates on these vehicles for 4WD type problems. The first thing you should do is take it in, get the software updates, get any codes (usually history) removed, and then just drive the thing.

I see so many of these type of complaints. In most cases, the software update fixes the problem. This is the way things are going in the automotive world.

Ian

Reply to
shiden_kai

From what the dealer and Ian said, I think the firmware will fix it. $80 software upgrade cuz I'm out of warranty period.

can someone get me detail on this TSB?

01410 - POOR PERFORMANCE FROM A STOP IN 2WD, AUTO OR 4WD HI. 2003, 2003 CADILLAC EXT ALSO INCLUDED. *TT

Regards,

-- Mike

shiden_kai wrote:

Reply to
Mike Brancato

I would go in and talk to the service manager about this. Yes, you are out of warranty.....but really, why should you pay for a software upgrade? Obviously, the software code is/was faulty from the factory. Software doesn't "break"....it's either right or it's wrong. In the case of the Trailblazers, it has been wrong a number of times. Obviously, you want to be nice, but firm. Perhaps you can use the example of computer motherboard manufacturers providing free bios updates regardless of whether the board is under warranty or not.

That number doesn't compute. I did just look at the bulletins for "driveline/axle" on your vehicle. Out of 7 bulletins, 4 of them include software updates for various transfer case related complaints.

I'll include them below....just the relevent info so that you can see if it matches your complaint.

Delayed Engagement of Front Wheels During a Slip Condition (Reprogram Transfer Case Control Module (TCCM)) #04-04-21-001 - (May 14, 2004) Delayed Engagement of Front Wheels During a Slip Condition (Reprogram Transfer Case Control Module (TCCM))

2004 Buick Rainier

2002-2004 Chevrolet TrailBlazer, TrailBlazer EXT

2002-2004 GMC Envoy, Envoy XL

2004 GMC Envoy XUV

2002-2004 Oldsmobile Bravada

with New Venture Gear (NVG) 126 (RPO NP4) or NVG 226 (RPO NP8) Transfer Case

Condition Some customers may comment on a hesitation or delayed engagement of the front wheels during a slip condition.

This condition may manifest itself in the normal AWD mode for the Bravada and Rainier models, and in the Auto 4WD mode for the TrailBlazer and Envoy models.

Correction Reprogram the Transfer Case Control Module (TCCM) using normal SPS procedures using TIS software version 11.5 released November 10th, 2003 or newer. Refer to Transfer Case Control Module Reprogramming for additional information.

2002 vehicles will require the replacement of the transfer case control module prior to reprogramming.

Inoperative 4WD/AWD Lamps, Inoperative 4WD/AWD System (Reprogram Transfer Case Control Module Using Labor Operation Code N8521) #02-04-21-006D - (Mar

24, 2004) Inoperative 4WD/AWD Lamps, Inoperative 4WD/AWD System (Reprogram Transfer Case Control Module Using Labor Operation Code N8521)

2004 Buick Rainier

2002-2004 Chevrolet TrailBlazer, TrailBlazer EXT

2003-2004 Chevrolet Avalanche, Silverado, Suburban, Tahoe

2002-2004 GMC Envoy, Envoy XL

2003-2004 GMC Sierra, Yukon, Yukon XL

2004 GMC Envoy XUV

2002-2004 Oldsmobile Bravada

with Electronic Shift or Active Transfer Case (RPOs NP1, NP4 or NP8)

This bulletin is being revised to add information to Step 5 of the procedure. Please discard Corporate Bulletin Number 02-04-21-006C (Section

04 -- Driveline/Axle).

Condition Some customers may comment that the 4WD/AWD indicator lights on the selector switch do not work, or the 4WD/AWD system may be inoperative and/or the service 4WD light is illuminated. The condition is typically intermittent and always occurs at key-up.

Cause The Transfer Case Control Module (TCCM) has not received the wake-up call during key-up and has remained in the "sleep mode".

When the TCCM is in the "sleep mode", it will not communicate with the class II bus or the Tech 2®.

Correction 1.. Try to communicate with the TCCM. If no communication, go to step 2. If communication is possible, go to step 5. 2.. Remove the underhood (ATCM or TREC) TCCM fuse. 3.. Wait 30 seconds. 4.. Reinstall the fuse. The module should "wake up" and communicate with the Tech 2®. 5.. Check for codes in the TCCM. If a C0550 is found current or in history with or without other codes, replace the module and go to step 6. 6.. Reprogram the TCCM using normal SPS procedures, using TIS software version 3 released March 8th, 2004 or newer. 7.. Verify operation and that no codes are present. Service 4WD Light On, 4WD Inoperative, Diagnostic Trouble Codes (DTC) C0300 and/or C0305 Set (Reprogram Transfer Case Control Module (TCCM)) #03-04-21-005 - (Jun 5, 2003) Service 4WD Light On, 4WD Inoperative, Diagnostic Trouble Codes (DTC) C0300 and/or C0305 Set (Reprogram Transfer Case Control Module (TCCM))

2003 Chevrolet Avalanche, Silverado, Suburban, Tahoe, TrailBlazer

2003 GMC Envoy, Sierra, Yukon, Yukon XL

2003 Oldsmobile Bravada

with 4WD (RPOs NP4, NP8)

Condition Some customers may comment that the Service 4WD light is on and/or the 4WD is inoperative.

Cause Condition may be caused by a TCCM calibration issue.

Correction Follow the service procedure below for diagnosis and repair of this condition.

1.. With a scan tool, select the TCCM DTCs. a.. If TCCM DTCs C0300 or C0305 are present in the TCCM, continue with TCCM reprogramming in Step 2. b.. If TCCM DTC C0374 is present with any of the above codes, disregard and clear the DTC and continue with TCCM reprogramming in step 2. c.. If TCCM DTC C0374 is present alone with none of the above listed codes, additional diagnosis is required. Refer to Service Information (SI) for proper diagnosis of the applicable vehicle. d.. If TCCM DTC C0550 is present, refer to DTC C0550 in SI for proper diagnosis of the applicable vehicle. 2.. Clear all DTCs and reprogram the TCCM with TIS version 3.5 or newer released to the dealers on 3-22-03. Refer to Transfer Case Control Module Reprogramming (SI Document ID #727487). Shudder, Rocking Motion, Binding, Feels Like Vehicle is Stuck in 4WD (Crow Hop) When Turning at Low Speeds (Replace Transfer Case Encoder Sensor and Reprogram TCCM) #02-04-21-008A - (Feb 13, 2003) Shudder, Rocking Motion, Binding, Feels Like Vehicle is Stuck in 4WD (Crow Hop) When Turning at Low Speeds (Replace Transfer Case Encoder Sensor and Reprogram TCCM) 2002-2003 Chevrolet TrailBlazer

2002-2003 GMC Envoy

2002-2003 Oldsmobile Bravada

This bulletin is being revised to update the service procedure and incorporate the fluid exchange. Please discard Corporate Bulletin Number

02-04-21-008 (Section 04 -- Driveline Axle).

Condition Some customers may comment that when turning, the vehicle feels like it is binding, or the vehicle feels like it is stuck in 4WD (crow hop), or that the 4WD system is not working correctly. A shudder type sensation is felt.

Technician Diagnosis This intermittent condition may be difficult to duplicate. The potential is there at all times for the Bravada. The potential is only present in the Auto Mode of the transfer case with the TrailBlazer or Envoy.

Correction

Important It is extremely important to check all of the tires before repairs are attempted for these types of customer concerns. Mismatched tires may cause these type of customer concerns. Inspect the tires in the following areas:

a.. Ensure that the tires are inflated to the recommended tire pressure as listed on the tire placard on the driver's door. b.. Use a tire tread depth gauge to determine the tread depth. The tire tread depth must be nearly equal on all four corners of the vehicle. c.. Ensure that the tires are all the same brand, size, and tread design.

Important Pay particular attention so that the proper parts are replaced. The parts terminology is somewhat confusing. You will be replacing the encoder (sensor) and gasket not the complete motor assembly.

Currently, the General Motors Parts Catalog lists the following names:

a.. Motor Asm, Trfer Case Encoder (This is the Encoder (Sensor). It looks like a donut with three (3) contacts on one side). b.. Gasket. c.. Actuator Asm, Trfer Case Four Whl Drv (This is the complete motor assembly consisting of the Motor and housing, the Motor Asm, the Trfer Case Encoder (Sensor), and the gasket).

Use the following procedure to replace the Motor Asm, Trfer Case Encoder (Sensor) and Gasket.

Nice, eh?

Ian

Reply to
shiden_kai

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.