C0310

Circuit Description
The transfer case encoder motor is a permanent magnet D.C. motor and gear reduction assembly. The encoder motor is controlled with a Pulse Width Modulated (PWM) circuit within the transfer case shift control module. This circuit consists of a power supply relay (Motor A) circuit that supplies voltage to the motor through CKT 1552. The Motor B circuit (CKT 1553) is a PWM driver that varies the duty cycle to control the amount of current through the motor to ground.
This DTC detects an open on circuits 1552 and 1553, an open motor.

Conditions for Setting the DTC
- The system will test the motor circuits by checking for unwanted voltage.
- The system supplies voltage on the Motor A circuit and reads the voltage back on the Motor B circuit.
- The transfer case shift control module senses no voltage return on circuits 1552 or 1553.
- If the system detects a problem with the circuits, the DTC is logged.

Action Taken When the DTC: Sets
All clutch activation (slip control) will be disabled. The SERVICE indicator (AWD/4WD) lamp will be latched on for the remainder of the current ignition cycle.

Conditions for Clearing the DTC
- Current DTC
The transfer case shift control module will clear the DTC if the condition for setting the DTC no longer exists.
- History DTC
- Once 100 consecutive ignition cycles without a fault present.
- A scan tool CLEAR CODES command.

Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
4. This step determines if circuit 1552 is open.
5. This step determines if circuit 1553 is open.





DTC C0310 Motor A/B Circuit Open