Driveline Indicators

4WD 

The IPC illuminates the 4WD indicator when the PCM detects that the 4WD is requested. The IPC receives a class 2 message from the PCM requesting illumination. The IPC also performs the displays test at the start of each ignition cycle. The indicator illuminates for approximately 3 seconds.

SERVICE 4WD 

The IPC illuminates the SERVICE 4WD indicator in the message center when the automatic transfer case module (ATC) detects a malfunction in the four wheel drive system. The IPC receives a class 2 message from the ATC requesting illumination.