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Service Indicator Inoperative

Service Indicator Inoperative





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 controls the Service indicator lamp by sending the IPC a Class 2 message. This lamp may be controlled with the scan tool using the IPC device controls.

Test Description
The number refers to the step number on the diagnostic table.
2. This step determines whether the failure is the result of a faulty transfer case shift control module or the IPC.