Power Door Locks Malfunction
Power Door Locks Malfunction
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (with HP2) (Initial Inspection and Diagnostic Overview)Diagnostic System Check - Vehicle (without HP2) (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The driver and front passenger power door lock switches are integral components of the driver door lock/window switch and passenger door lock/window switch. The switches consist of 2 positions, lock and unlock, and are in the normally open state. When placed in either the lock or unlock positions, the switches provide a direct input to there respective door control module. When a power door lock switch is operated to the lock or unlock position, the associated door control module responds by sending a serial data message indicating a change in the switch's position. This serial data message is received by the opposite door control module as well as the body control module (BCM). The driver door lock/window switch and passenger door lock/window switch respond to the lock/unlock request by activating their associated power door lock motors to the appropriate direction to lock or unlock the front doors. The BCM is responsible for controlling the left rear door latch, right rear door latch and for the endgate lock actuator. The BCM, upon receipt of a lock or unlock serial data signal, will control either the rear door lock or unlock relay. When the appropriate door lock relay is energized, the rear power door latches and endgate lock actuator will lock or unlock the rear doors and endgate.
Reference Information
Schematic Reference
Door Lock/Indicator Schematics (Door Lock/Indicator Schematics)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Power Door Locks Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
Command the doors to LOCK and UNLOCK by using the driver and passenger door lock switches, each door should perform the LOCK and UNLOCK function from each switch.
If the driver door does not LOCK or UNLOCK, refer to Driver Door Lock Malfunction.
If the passenger door does not LOCK or UNLOCK, refer to Passenger Door Lock Malfunction
If a rear door does not LOCK or UNLOCK, refer to Rear Door Lock Malfunction.
If liftgate does not LOCK or UNLOCK, refer to Liftgate Locks Malfunction.
Circuit/System Testing
Driver Door Lock Malfunction
1. Ignition OFF, disconnect the harness connector at the driver door latch.
2. Test for less than 2 ohms between the control circuit terminal 3 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 driver door lock/window switch.
3. Test for less than 2 ohms between the control circuit terminal 2 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 driver door lock/window switch.
4. Ignition ON, connect a test lamp between the control circuit terminal 3 and control circuit terminal 2.
5. Command the Door Lock/Unlock with a scan tool. The test lamp should briefly illuminate when commanding the LOCK and UNLOCK states.
• If the test lamp is always OFF during either of the commands, test either control circuit for a short to ground. If the circuits test normal, replace the driver door lock/window switch.
6. If the circuits test normal, test or replace the driver door latch.
Passenger Door Lock Malfunction
1. Ignition OFF, disconnect the harness connector at the passenger door latch.
2. Test for less than 2 ohms between the control circuit terminal 5 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 passenger door lock/window switch.
3. Test for less than 2 ohms between the control circuit terminal 6 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 passenger door lock/window switch.
4. Ignition ON, connect a test lamp between the control circuit terminal 5 and control circuit terminal 6.
5. Command the door to LOCK and UNLOCK by using the passenger door lock/window switch. The test lamp should briefly illuminate when commanding the LOCK and UNLOCK states.
• If the test lamp remains OFF during either of the commands, test either control circuit for a short to ground. If the circuits test normal, replace the passenger door lock/window switch.
6. If the circuits test normal, test or replace the passenger door latch.
Rear Door Lock Malfunction
1. Ignition OFF, disconnect the X1 harness connector at the I/P fuse block.
2. Test for less than 1 ohm between the ground circuit terminal E1 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance
3. Connect the X1 harness connector and disconnect the X3 harness connector at the I/P fuse block.
4. Connect a test lamp between control circuit terminal A2 and ground.
5. Ignition ON, command the Lock Rear Doors with a scan tool. The test lamp should briefly illuminate during the LOCK command.
• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
• If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
6. Connect a test lamp between control circuit terminal A3 and B+.
7. Command Unlock Rear Doors with a scan tool. The test lamp should briefly illuminate during the UNLOCK command.
• If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
• If the test lamp is always OFF, test the control circuit for a short to voltage or and open/high resistance. If the circuit tests normal, replace the BCM.
8. Ignition OFF, connect the harness connector at the I/P fuse block. Disconnect the harness connector at the appropriate rear door latch.
9. Ignition ON, connect a test lamp between the appropriate control circuit terminals listed below:
* Left rear door latch terminals 2 and 3
* Right rear door latch terminals 5 and 6
10. Command the Lock Rear Doors and Unlock Rear Doors with a scan tool. The test lamp should briefly illuminate when commanding the LOCK and UNLOCK states.
• If the test lamp is always OFF, test either control circuit for a short to ground or an open/high resistance. If the circuit tests normal and the circuit fuse is good, replace the I/P fuse block.
• If the test lamp is always ON, test either control circuit for a short to voltage. If the circuit tests normal, replace the I/P fuse block.
11. If all circuits test normal, test or replace the rear door latch.
Liftgate Lock Malfunction
1. Ignition OFF, disconnect the harness connector at the endgate lock actuator.
2. Connect a test lamp between the control circuit terminal A and control circuit terminal B.
3. Ignition ON, command the liftgate door lock actuator to LOCK and UNLOCK by using the driver door lock/window switch. The test lamp should illuminate during the LOCK and UNLOCK command.
• If the test lamp is always OFF, test either control circuit for a short to ground or an open/high resistance. If the circuit tests normal and the circuit fuse is good, replace the I/P fuse block.
• If the test lamp is always ON, test either control circuit for a short to voltage. If the circuit tests normal, replace the I/P fuse block.
4. If all circuits test normal, test or replace the endgate lock actuator.
Component Testing
1. Ignition OFF, disconnect the harness connector at the appropriate door latch.
2. Install a 15A fused jumper wire between one of the control terminals and 12V. Momentarily install a jumper wire between the other control terminal and ground. Reverse the jumper wires at least two times, the door latch should perform the LOCK/UNLOCK functions.
• If it does not perform as specified, replace the door latch
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Front Side Door Lock Replacement (Front Side Door Lock Replacement)
* Rear Door Lock Replacement (Rear Door Lock Replacement)
* Endgate Latch Replacement ()
* Instrument Panel Electrical Center or Junction Block Replacement - Left Side ()
* Control Module References (Programming and Relearning) for BCM, driver door lock/window switch or passenger door lock/window switch replacement, setup and programming