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DTC C0402

DTC C0402

Diagnostic Instructions


• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• 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 Short to Ground Open/High Resistance Short to Voltage Signal Performance
Control C0402 02, C0406 0B C0402 04 - -
Low Reference - C0402 04 - -


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 modulated signal (PWM-signal). The solenoid valve controls the hydraulic pressure to the torque converter's clutch pack. 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 clutchsolenoid valve. An error is detected if the current is greater than the current which corresponds to less than 2 Ω 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

Connector End View Reference

Component Connector End Views

Description and Operation

Rear Drive Axle Description and Operation

Electrical Information Reference


• Circuit Testing

• Connector Repairs

• Testing for Intermittent Conditions and Poor Connections

• Wiring Repairs


Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

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.



1. Engine running in stationary.

2. Observe the scan tool Rear Drive Clutch Status parameter. The scan tool must display TEMPORARILY LIMITED when stationary.

3. If the status parameter does not indicate TEMPORARILY LIMITED

3.1. Verify that DTC C0402 is not set.

3.2. If the DTC is set, replace K47 rear differential clutch control module and Q48 for the rear drive clutch solenoid valve.

3.3. If the DTC is not set:

3.4. Everything is OK.

4. If the status parameter indicates TEMPORARILY LIMITED

5. Everything is OK.


Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for rear differential clutch control module replacement, setup, and programming