For 1990-2009 cars only
Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit Description
The service 4WD indicator is located in the instrument panel cluster (IPC) and shares the common power and ground of the IPC. The transfer case shift control module turns ON or OFF the SERVICE 4WD indicator by sending the IPC a class 2 message.
Reference Information
Schematic Reference
Transfer Case Control Schematics
Connector End View Reference
Description and Operation
Transfer Case Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF, disconnect connectors C1 and C2 of the transfer case shift control module.
- Ignition ON, the Service 4WD indicator on the IPC should be OFF.
| ⇒ | If the Service 4WD indicator is ON, repair or replace the IPC. |
| ⇒ | If the Service 4WD indicator is OFF, replace the transfer case shift control module. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for transfer case shift control module replacement, setup, and programming. |
