Power Door Locks Inoperative - Rear

Power Door Locks Inoperative - Rear

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information






Circuit/System Description

The rear door lock actuators are controlled by the body control module (BCM) through the LOCK and UNLOCK relays, and the relays are controlled by the BCM through low side drive control circuits.

Circuit/System Verification

Command the rear doors to Lock and Unlock with a scan tool. The rear doors should lock and unlock.

Circuit/System Testing

1. Disconnect the harness connector at the affected door latch.
2. Test for less than 1.0 ohm between the actuator control circuit terminal A and ground.

^ If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal replace the UNLOCK relay.

3. Test for less than 1.0 ohm between the actuator control circuit terminal B and ground.

^ If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal replace the LOCK relay.

4. Connect a test lamp between the control circuit terminal A and the control circuit terminal B.
5. Command the rear doors Locked and Unlocked with a scan tool. The test lamp should flash when changing between the commanded states.

^ If the test lamp does not flash during both commanded states, replace the affected relay.

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

Repair Instructions

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

Rear Side Door Latch Replacement