C0402
DTC C0402
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 Descriptors
DTC C0402 02
- Transfer Case Solenoid Valve Short to Ground
DTC C0402 04
- Transfer Case Solenoid Valve Open
DTC C0402 42
- Transfer Case Solenoid Valve Calibration Not Programmed
DTC C0402 43
- Transfer Case Solenoid Valve EEPROM Incorrect Programming
DTC C0402 4B
- Transfer Case Solenoid Valve Calibration Not Learned
DTC C0402 61
- Transfer Case Solenoid Valve Stuck
Diagnostic Fault Information
Circuit/System Description
The rear drive clutch solenoid valve is internal to the torque transfer device housing. The rear differential clutch control module supplies battery voltage to the control circuit and ground to the low reference circuit of the solenoid valve. The solenoid valve is controlled by a pulse width modulation (PWM) signal. The solenoid valve controls the hydraulic pressure to the clutch package of the torque transfer device. The locking level of the torque transfer device depends on the engagement of the clutch package.
Conditions for Running the DTC
C0402 02, C0402 42, C0402 43 and C0402 4B
* The ignition is ON.
* The circuits are tested during start up of the rear differential clutch control module.
C0402 04
The ignition is ON.
C0402 61
* Engine running.
* When requested torque is less than 25 Nm (18 lb ft) and the calculated temperature is in the range of 0-90°C (32-194°F).
Conditions for Setting the DTC
C0402 02
Voltage is applied to the rear drive clutch solenoid valve. An error is detected if the current is greater than the current which corresponds to less than 2 ohm resistance in the solenoid valve.
C0402 04
The measured current deviates from the nominal value with more than 200 mA for more than 100 ms.
C0402 42 and C0402 43
The solenoid valve calibration values stored in the rear differential clutch control module EEPROM are invalid or out of range.
C0402 4B
There are no solenoid valve calibration values stored in the differential clutch control module EEPROM.
C0402 61
An error is detected if the solenoid valve is not engaging adequately over a predetermined test sequence.
Action Taken When the DTC Sets
C0402 02, C0402 04 and C0402 61
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.
C0402 42, C0402 43 and C0402 4B
An error record is stored in the rear differential clutch control module. No action will be performed.
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
Note: 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.
Verify DTC C0402 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.
Control Module References (Programming and Relearning) for rear differential clutch control module replacement, setup, and programming