Inoperative 4WD Lamp And System (Reprogram Transfer Case Control Module) (SBO4-05-S002)

WARNING: This page is about the Ascender LS, 4.2 S, 4WD, which is a different variant/trim than selected.

Publication date: 2006-08-01
Reference number: SBO4-05-S002
Supersedes refnos: SB06-05-S002

INOPERATIVE 4WD LAMP AND SYSTEM (REPROGRAM TRANSFER CASE CONTROL MODULE)

TECHNICAL SERVICE BULLETIN

Reference Number(s): SB06-05-S002, Date of Issue: AUGUST 01, 2006

ISUZU:	2003-2004 Isuzu Ascender
AFFECTED VEHICLES:	2003-2004 Isuzu Ascender (US/UT) with 4WD

Superceded Bulletin(s): SB04-05-S002

NOTE: This Bulletin Supersedes SB04-05-S002

Affected Vehicles

2003-2004 Isuzu Ascender (US/UT) with 4WD

Service Information

This bulletin is being revised to add a model year and to update and add additional service information.

Condition

Some customers may comment that the 4WD indicator lights on the selector switch do not work, or the 4WD system may be inoperative and/or the service 4WD light is illuminated. Upon investigation, the technician may find DTC C0550 set.

Possible 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 on the Class 2 bus or the Tech 2.

Correction:

Reprogram the transfer case module.

Service Procedure

Try to communicate with the TCCM. If no communication, go to step 2. If communication is possible, go to step 5.
Remove the underhood ATC Fuse 8.
Wait 30 seconds.
Reinstall the fuse, the module should "wake up" and communicate with the Tech 2.
Check for codes in the TCCM, if a C0550 is found, replace the module and go to the next step. If other codes are found, they may be related to this concern, go to the next step and recheck for codes.
Reprogram the TCCM using normal SPS procedures and IDS Version 9 or newer.
Verify operation and that no codes are present.

Warranty Claim Information

Use the following labor operation:

WARRANTY CLAIM INFORMATION

Operation	Operation No.	Task	Time	Trouble
Control Module	05K4121D	Reprogram	Use Applicable Published Labor Time	Code 71

NOTE:

Labor Time includes administrative time allowance.
Information released on paper and electronic format prior to bulletin release cannot be updated. For the most current and up to date information refer to IsuzuONE.com
Always refer to the Isuzu Service Policy Procedure Manual for specific details on warranty coverage and policies.