Service 4WD

Automatic Transfer Case (ATC) module sends a class 2 serial data message to Instrument Panel Cluster (IPC) to instruct IPC when to turn on SERVICE 4WD indicator. SERVICE 4WD indicator illuminates when one or more of the following conditions exists:

• System related DTC is set.
• Instrument cluster cannot communicate with ATC module on Class 2 serial data line.
• Instrument cluster receives a Class 2 serial data message from ATC module requesting SERVICE 4WD indicator on.