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Service Indicator Always On



Service Indicator Always On

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

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

Step 1 - Step 4: