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DTC C0406

DTC C0406

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 Descriptor

DTC C0406 0B

Transfer Case Solenoid Valve Control Circuit High Current

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

The ignition is ON.

Conditions for Setting the DTC


• The rear differential clutch control module detects a short to ground on the control circuit of the rear drive clutch solenoid valve.

• The rear differential clutch control module detects a current more than 11 A on the control circuit of the rear drive clutch solenoid valve.


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

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


1. Engine running and vehicle stationary.

2. Check using a scan tool that the rear clutch status parameter indicates Temporarily limited.

3. If the parameter does not show Temporarily limited

3.1. Check that DTC C0406 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 parameter shows 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