GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2007 🢒 Acadia - 2WD 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC C0393

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 Solenoid Control Circuit Short to Ground or Open

DTC C0393 0B:  Rear Axle Coupling Solenoid Control Circuit Current Above Threshold

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

AWD Actuator High Control Circuit

C0393 06

C0393 06

C0393 0B

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AWD Actuator Low Control Circuit

C0393 06

C0393 06

C0393 0B

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Circuit/System Description

The rear differential clutch control module (CCM) provides a power and ground switching circuits to the actuator. The actuator receives current from the CCM 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 actuator circuits.
    • A short to ground is detected on the high or low actuator 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

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector X1 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:
    3. • Actuator high circuit terminal 5
    • Actuator low 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:
    4. • Actuator high circuit terminal 5
    • Actuator low 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 actuator high terminal 5 and the actuator low circuit terminal 3.
    5. ⇒If greater than the specified range, test both control circuits for an open/high resistance. If the circuits test normal, rear differential clutch assembly.
  5. If all circuits test normal, replace the CCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Control Module References for CCM replacement, setup, and programming
    •  Differential Clutch Drum Assembly Replacement for the rear differential assemble replacement.