C0315

DTC C0315

Circuit Description
The transfer case motor is a bi-directional, permanent magnet, DC motor. When energized, the motor through a series of gears, rotates a shaft which moves the mode, and the range forks to shift the transfer case. The transfer case shifts between 4H, AUTO 4WD, 2H, N, and 4L ranges. The motor becomes energized through motor control A, or through motor control B. The ground is provided by the opposing motor control circuit, and then grounded through the transfer case shift control module ground circuit.

This DTC detects an open or a short to voltage in the motor ground circuit.

DTC Descriptor
This diagnostic procedure supports this DTC:
DTC C0315 Motor Ground Circuit Open

Conditions for Running the DTC
^ The ignition is ON.
^ The system voltage is 9 - 16 volts.

Conditions for Setting the DTC
The system tests 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 to voltage 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 logged.

Action Taken When the DTC Sets
^ The SERVICE 4WD indicator remains illuminated for the remainder of the current ignition cycle.
^ All shifting is disabled.

Conditions for Clearing the DTC
^ The transfer case shift control module clears the DTC if the condition for setting the DTC does not exist.
^ A history DTC clears after 100 consecutive ignition cycles without a fault present.
^ History DTCs can be cleared using a scan tool.

Test Description

Steps 1-5:

These numbers correspond to the step numbers on the diagnostic table.
2. This step listens for an audible motor noise when the encoder motor operates. Command both the ON and OFF states. Repeat the commands as necessary.
3. This step tests the motor ground circuit for an open.