B324A

DTC B324A

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 Descriptor
DTC B324A 02
- Rear Cargo Door Unlock Motor Circuit Short to Ground

Diagnostic Fault Information





Circuit/System Description

When the body control module (BCM) receives a liftgate release command, it will provide voltage to one side of the relay and ground to the other side of the relay. This will energize the relay causing the switch side of the relay to close and will then provide B+ voltage to the liftgate latch.

Conditions for Running the DTC

* The system voltage is 9-16 volts.
* When the relay is actively commanded by the BCM

Conditions for Setting the DTC

The BCM detects a short to ground in the liftgate release relay control circuit.

Actions Taken When DTC Sets

The liftgate latch will be inoperative.

Conditions for Clearing the DTC

* The DTC will be current for as long as the fault is present.
* When the fault is no longer present, the DTC will be a history DTC.
* A history DTC will clear after 50 ignition cycles.

Reference Information
Schematic Reference

Release Systems Schematics (Release Systems Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Rear Hatch/Gate Description and Operation (Rear Hatch/Gate 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

Doors UNLOCKED, command the M31 liftgate latch assembly to release by pressing the S58A rear compartment lid release switch - exterior. The M31 liftgate latch assembly should release the liftgate.

Circuit/System Testing

1. Ignition OFF, disconnect the X4 harness connector at the K9 BCM.
2. Momentarily install a 3A fused jumper wire between the control circuit terminal 8 and B+.
3. Listen for the Liftgate Release PCB relay clicks.

• If the Liftgate Release PCB relay does not perform as specified, test the control circuit for an open/high resistance. If the circuit tests normal, replace the X50D fuse block - underhood.

• If the fuse within the jumper wire opens, test the control circuit for a short to ground. If the circuit tests normal, replace the X50D fuse block - underhood.

4. If all circuits test normal, replace the K9 BCM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Accessory Wiring Junction Block Replacement (Accessory Wiring Junction Block Replacement)

Control Module References (Programming and Relearning) For BCM replacement, setup and programming