Test Description

WARNING: This page is about a different car, the 2004 GMC Yukon XL and 2004 GMC Yukon. However, it is still accessible from the selected car via links, so may be relevant.

The number below refers to the step number on the diagnostic table.

2: This step determines whether the failure is the result of a malfunctioning transfer case shift control module or the IPC.

Service Indicator Always On

Step	Action	Yes	No
Schematic Reference: Transfer Case Control Schematics Connector End View Reference: Transfer Case Control Connector End Views
1	Did you perform the Diagnostic System Check - Transfer Case?	Go to Step 2	Go to Diagnostic System Check - Transfer Case
2	In the IPC Data List, test the Service 4WD input/output. Is the Service 4WD indicator commanded ON?	Go to Step 3	Go to Step 4
3	Replace the transfer case shift control module. Refer to Transfer Case Shift Control Module Replacement . Did you complete the repair?	Go to Step 5	-
4	Replace the instrument panel cluster. Refer to Instrument Panel Cluster (IPC) Replacement in Instrument Panel, Gages, and Console. Did you complete the repair?	Go to Step 5	-
5	Use the scan tool in order to clear the DTCs. Operate the vehicle in order to determine if the symptom has been corrected. Is the symptom still present?	Go to Step 1	System OK