Circuit Description
The SERVICE indicator (AWD/4WD) lamp is located in the instrument cluster. It receives ignition voltage from a 10 amp gauge fuse through CKT 39. This circuit also supplies all of the gauges with ignition voltage. The transfer case shift control module controls the SERVICE indicator (AWD/4WD) lamp by sending the instrument cluster a Class 2 message. This lamp maybe controlled with the scan tool using the instrument cluster device controls.
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
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This step determines if the transfer case shift control module has electronic control of the Service Indicator.
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This step determines if there is an internal fault with the transfer case shift control module.
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This step check CKT 1567 for open.
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This step check CKT 39 for open.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the Transfer Case Diagnostic System Check performed? | -- | Go to Step 2 | |
Does the service indicator (4WD/AWD) lamp light? | -- | Go to Step 3 | Go to Diagnostic System Check - Instrument Cluster in Instrument Cluster | |
Replace the transfer case shift control module. Refer to Transfer Case Shift Control Module Replacement . Is the action complete? | -- | Go to Step 4 | -- | |
Have all the ATC components been reconnected and properly mounted? | -- | Go to Step 5 | -- | |
Clear all the ATC DTCs. Have all the ATC DTCs been cleared? | -- | -- |
