Inspection and Verification
INSPECTION AND VERIFICATION1. Verify the customer concern.
2. The battery voltage must be at normal operating levels in order for the PLG to open and close correctly. Make sure the battery and charging systems are operating correctly before proceeding with the PLG 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 are provided to the VCM.
If the scan tool does not communicate with the VCM:
- check the VCM connection to the vehicle.
- check the scan tool connection to the VCM.
- refer to Information Bus (Module Communications Network), No Power To The Scan Tool, to diagnose no communication with 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 Information Bus (Module Communications Network) to diagnose no response from the power liftgate module (PLG) or smart junction box (SJB).
8. Carry out the network test.
- If the scan tool responds with no communication for one or more modules, refer to Information Bus (Module Communications Network).
- If the network test passes, retrieve and record continuous memory DTCs.
9. Clear the continuous DTCs and carry out the self-test diagnostics for the PLG or SJB.
10. If the DTCs retrieved are related to the concern, go to the Power Liftgate (PLG) Module DTC Chart or the Smart Junction Box (SJB) DTC Chart. For all other DTCs, refer to Body Control Systems (Multifunction Electronic Control Module). Power Liftgate (PLG) Module DTC Chart Smart Junction Box (SJB) DTC Chart
11. If no DTCs related to the concern are retrieved, GO to Symptom Chart. Symptom Related Diagnostic Procedures