Test Description
The numbers below refer to the step numbers on the diagnostic table.
- This step inspects for lack of communication that may be due to a partial malfunction of the Class 2 serial data circuit or due to a total malfunction of the Class 2 serial data circuit. The specified procedure determines the particular condition.
- The presence of DTCs indicates that the transfer case shift control module has detected a fault. Go to symptoms for other concerns.
- The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure compiles all the available information before tests are performed.
- Vehicle speed is provided to the transfer case shift control module via Class 2 and can effect the setting of DTC C0300. Perform the diagnostics for powertrain DTC P0502 and DTC P0503 first.
- Perform diagnostics for DTC C0300 and DTC C0305 first before addressing other DTCs. DTC C0300 and DTC C0305 can be responsible for setting other DTCs.
