Power Door Locks Inoperative - Endgate/Liftgate

Power Door Locks Inoperative - Endgate/Liftgate

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.

Diagnostic Fault Information





Circuit/System Description

The liftgate module (LGM) is directly connected to the liftgate lock actuator through the lock actuator lock and unlock control circuits. Once a door lock or unlock request has been received, the module will supply battery voltage to one side of the actuator and ground the other causing the liftgate to lock or unlock.

Reference Information
Schematic Reference

Door Lock/Indicator Schematics (Door Lock/Indicator Schematics)
Connector End View Reference

Component Connector End Views (Component Connector End Views)
Description and Operation

Power Door Locks Description and Operation (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 (Control Module References) for scan tool information

Circuit/System Verification

Command the liftgate to LOCK and UNLOCK with a scan tool. The liftgate should LOCK and UNLOCK.

Circuit/System Testing

Liftgate Lock Actuator Circuit Test
1. Ignition OFF, disconnect the X2 harness connector at the liftgate latch.
2. Ignition OFF, test for less than 5.0 ohms between the control circuit terminal A and ground.

• If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the LGM.

3. Ignition OFF, test for less than 5.0 ohms between the control circuit terminal B and ground.

• If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the LGM.

4. Connect a test lamp between control circuit terminal A and control circuit terminal B.
5. Command the liftgate to LOCK and UNLOCK with a scan tool. The test lamp should turn ON when commanding the LOCK and UNLOCK states.

• If the test lamp remains OFF during either of the commands, test for a short to ground on either control circuit. If the circuits test normal, replace the LGM.

6. If all circuits test normal, test or replace the liftgate latch.

Repair Instructions

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

Control Module References (Control Module References) for LGM replacement, programming, and setup