C0315

DTC C0315

Circuit Description
The transfer case motor is a bidirectional, permanent magnet, D.C. motor. When energized through Motor Control A or Motor Control B. the ground is provided by the opposing Motor Control circuit and then grounded through the transfer case shift control module's ground circuit.
This DTC detects only an open in the module ground circuit and not the Motor Control circuits.

Conditions for Setting the DTC
The system test the motor circuits:
^ First, the system checks for unwanted voltage.
^ Then, the system supplies voltage on each of the motor circuits and reads the voltage back on the other circuit.
^ After the system checks for opens and shorts on the motor circuits, its applies voltage through the motor and back to the module to ground.
^ If the system detects a high voltage on the ground circuit the DTC is loosed.

Action Taken When the DTC Sets
^ All shifting will be disabled.
^ The SERVICE 4WD indicator will be latched on for the remainder of the current ignition cycle.

Conditions for Clearing the DTC
^ The transfer case shift control module will clear the DTC if the condition for setting the DTC no longer exists.
^ A history DTC will clear after 100 consecutive ignition cycles without a fault present.
^ History DTCs can be cleared using a scan tool.





Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. Listen for an audible motor noise when the encoder motor operates. Command both the ON and OFF states. Repeat the commands as necessary.
3. Tests the Motor Ground circuit for an open.