Diagnostic System Check - Transfer Case

Diagnostic System Check - Transfer Case

Important: Read the Transfer Case Description and Operation to familiarize yourself with basic system operation.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. This step checks that the scan tool is communicating with the transfer case shift control module (TCCM).
3. This step checks the presence of DTCs which begin with "U" indicating some other module is not communicating.
4. This step checks to see if other modules are interfering with the TCCM operation.
6. This step checks for TCCM DTCs.
7. This step verifies if the TCCM has power and ground. The TCCM will not communicate without the Battery Positive Voltage circuit functioning.

Step 1 - Step 7:

Step 8 - Step 11:

Diagnostic System Check - Transfer Case