The Service 4WD indicator is located in the instrument cluster. It receives ignition voltage
The number below refers to the step number on the diagnostic table.
Step  | Action  | Yes  | No  | 
|---|---|---|---|
Schematic Reference: Transfer Case Control Schematics  | |||
1  | Was the Transfer Case Diagnostic System Check performed?  | Go to Step 2  | |
 Does the SERVICE 4WD message turn ON?  | Go to Step 3  | Go to Instrument Cluster Replacement in Instrument Panel, Gages, and Console  | |
3  | Replace the transfer case shift control module. Refer to Transfer Case Shift Control Module Replacement . Is the repair complete?  | Go to Step 4  | --  | 
4  | 
 Does the symptom re-occur?  | Go to Step 2  | System OK  |