For 1990-2009 cars

### 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 C0393 06: Rear Axle Coupling coil Control Circuit Short to Ground or Open/High Resistance
DTC C0393 0B: Rear Differential coil Control Circuit Current Above Threshold

### Diagnostic Fault Information

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

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
High Clutch coil Control Circuit | C0393 06 | C0393 06 | C0393 0B | --
Low Clutch coil Control Circuit | C0393 06 | C0393 06 | C0393 0B | --

### Circuit/System Description

The rear differential clutch control module (RDCCM) provides a power and ground switching circuits to the (AWD) coil. The coil receives current from the RDCCM through PWM low side driver, and converts that signal into torque through the clutch to the rear tires when all wheel drive (AWD) is requested.

### Conditions for Running the DTC

• | The ignition is ON.

• | Ignition voltage is greater than 9 volts.

### Conditions for Setting the DTC

• | An open is detected on the high or low clutch coil circuits.

• | A short to ground is detected on the high clutch coil circuit.

### Action Taken When the DTC Sets

One or more of the following actions may occur:

• | All Wheel Drive Off (AWD Disabled) DIC message.

• | Service All Wheel Drive (Service AWD) DIC message.

### Conditions for Clearing the DTC

• | The condition for the DTC is no longer present.

• | The DTC is not detected in 40 consecutive drive cycles.

### Reference Information

#### Schematic Reference

All-Wheel Drive Schematics

#### Connector End View Reference

Transfer Case Control Connector End Views

#### Description and Operation

All-Wheel Drive Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Scan Tool Data List for Scan Tool Information

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector C1 at the rear differential clutch control module .
2. Ignition ON, verify a test lamp does not illuminate between the following control circuit terminals and ground:

• | Coil supply circuit terminal 5

• | Low reference circuit terminal 3

⇒ | If the test lamp illuminates, test the appropriate control circuit for a short to voltage.

3. Ignition OFF, test for infinite resistance between the following control circuit terminals and ground:

• | Coil supply circuit terminal 5

• | Low reference circuit terminal 3

⇒ | If less than the specified value, test the appropriate control circuit for a short to ground.

4. Test for less than 5.0 ohms of resistance between the coil supply terminal 5 and the low reference circuit terminal 3.

⇒ | If greater than the specified range, test both control circuits for an open/high resistance. If the circuits test normal, replace the rear differential.

5. If all circuits test normal, replace the RDCCM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for RDCCM replacement, setup, and programming

The temperature sensor and coil internal in the differential, and is replace as an assembly. Refer to Differential Replacement