C0403
DTC C0403
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC C0403 62
- AWD Oil Filter Reverse Valve Stuck Open
Circuit/System Description
The differential clutch pump delivers hydraulic oil pressure to the rear drive clutch solenoid valve and the rear differential clutch solenoid valve. The pump is mounted to the torque transfer device housing. The pressure of the system is calculated by the rear differential clutch control module which monitors the differential clutch pump current levels. When the pressure reaches approximately 3200 kPa (464 psi), the rear differential clutch control module determines that the system pressure has been obtained and deactivates the differential clutch pump. If a voltage is detected after a predetermined time limit when the pump has been deactivated an error is detected. This condition indicates the pump is spinning backwards.
Conditions for Running the DTC
* The ignition is ON.
* Operating temperature range 0-80°C (0-176°F).
Conditions for Setting the DTC
The rear differential clutch control module detects voltage on the differential clutch pump control circuit 20 seconds after the pump has been deactivated indicating the pump is spinning in reverse direction.
Action Taken When the DTC Sets
One or more of the following actions may occur:
* All-wheel drive (AWD) is disabled
* Service Rear Axle is displayed on the driver information center.
Conditions for Clearing the DTC
* The condition for setting the DTC is no longer present.
* The DTC is not detected in 40 consecutive ignition cycles.
Reference Information
Schematic Reference
Rear Axle Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
Description and Operation
Rear Drive Axle Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
Engine running, observe the scan tool Rear Drive Clutch Status parameter. The scan tool should display TEMPORARILY LIMITED when stationary.
Circuit/System Testing
Important: The rear drive clutch solenoid valve is calibrated with and is part of the rear differential clutch control module. Both components must be replaced as a matched set.
1. Ignition OFF, replace the oil filter in the torque transfer device housing.
2. Drive the vehicle under normal operating conditions.
3. Verify DTC C0403 62 is not set.
• If the DTC is set, replace the K47 rear differential clutch control module/Q48 rear drive clutch solenoid valve assembly.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Differential Clutch Oil Filter Replacement (Differential Clutch Oil Filter Replacement)
* Control Module References (Programming and Relearning) for rear differential clutch control module replacement, setup, and programming