Inspection and Verification

Power Liftgate

Inspection and Verification

1. Verify the customer concern.

2. The battery voltage must be at normal operating levels for the power liftgate to open and close correctly. Make sure the battery and charging systems are operating correctly before proceeding with the power liftgate diagnosis.

3. Visually inspect for obvious signs of mechanical and electrical damage. Refer to the following chart.

Visual Inspection Chart






4. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.

5. NOTE: Make sure to use the latest scan tool software release.
If the cause is not visually evident, connect the scan tool to the Data Link Connector (DLC).


6. NOTE: The Vehicle Communication Module (VCM) LED prove-out confirms power and ground from the DLC (Data Link Connector) are provided to the VCM (Vehicle Communication Module).
If the scan tool does not communicate with the VCM (Vehicle Communication Module) :

- check the VCM (Vehicle Communication Module) connection to the vehicle.

- check the scan tool connection to the VCM (Vehicle Communication Module).

- refer to No Power To The Scan Tool, to diagnose no power to the scan tool.


7. If the scan tool does not communicate with the vehicle:
- verify the ignition key is in the ON position.

- verify the scan tool operation with a known good vehicle.

- refer to The PCM Does Not Respond To The Scan Tool, to diagnose no response from the PCM Pinpoint Test A: The PCM Does Not Respond To The Scan Tool.


8. Carry out the network test.
- If the scan tool responds with no communication for one or more modules, refer to Information Bus.

- If the network test passes, retrieve and record Continuous Memory Diagnostic Trouble Codes (CMDTCs).


9. NOTE: Carrying out the LTM (Liftgate/Trunk Module) initialization procedure will resolve concerns where the power liftgate has lost position or was not initialized correctly. For information, refer to Power Liftgate Initialization . Clear the CMDTCs (Continuous Memory Diagnostic Trouble Codes) and carry out the self-test diagnostics for the LTM (Liftgate/Trunk Module) or BCM (Body Control Module).

10. If the DTCs retrieved are related to the concern, go to the Liftgate/Trunk Module (LTM) DTC Chart or the Body Control Module (BCM) DTC Chart Trunk / Liftgate. For all other DTCs, refer to Body Control Systems.

11. If no DTCs related to the concern are retrieved, GO to Symptom Chart Symptom Related Diagnostic Procedures.