Service 4WD System

The service 4WD indicator is a LED display located in the instrument cluster. The Automatic Transfer Case (ATC) module sends a class 2 serial data message to the instrument cluster to instruct the instrument cluster when to turn ON the service 4WD indicator.

The service 4WD indicator will also turn ON when one of the following actions occurs:
^ The instrument cluster receives a class 2 serial data message from the ATC module requesting the service 4WD indicator be turned ON.
^ The instrument cluster can not communicate with the ATC module using class 2 serial data communications.
^ A Diagnostic Trouble Code (DTC) is stored related to the system malfunction.