Power Door Locks Malfunction
Power Door Locks Malfunction
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 body control module (BCM) monitors the voltage level of the door lock and door unlock signal circuits. When the central door lock switch is in the open position, the voltage level in the signal circuit will be near 0 V. When the central door lock switch is pressed to the lock or unlock position, a signal will be sent to the BCM requesting a lock or unlock command.
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
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Circuit Testing (Circuit Testing)
* Wiring Repairs (Wiring Repairs)
* Connector Repairs (Connector Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
1. Ignition ON, observe the scan tool BCM Central Door Lock Switch on Console parameter. The reading should be Inactive and change to Lock and Unlock when pushing the appropriate switch.
• If the reading does not change, refer to Central Door Lock Switch Malfunction.
2. Command the doors to LOCK and UNLOCK by using the central door lock switch, the doors should LOCK and UNLOCK when changing between the commanded states.
• If a door does not LOCK or UNLOCK, refer to Door Lock Malfunction.
• If all doors do not LOCK or UNLOCK, refer to All Door Locks inoperative.
Circuit/System Testing
Central Door Lock Switch Malfunction
1. Ignition OFF, disconnect the harness connector at the A20 radio/HVAC control.
2. Test for less than 5 ohm between the ground circuit terminal 17 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Central Door Lock Switch on Center Console parameter is Inactive.
• If the value is Lock , test the signal circuit terminal 12 for a short to ground. If the circuit tests normal, replace the K9 BCM.
• If the value is Unlock , test the signal circuit terminal 13 for a short to ground. If the circuit tests normal, replace the K9 BCM.
4. Install a 3 A fused jumper wire between the signal circuit terminal 12 and ground. Verify the scan tool Central Door Lock Switch on Center Console parameter is Lock.
• If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
5. Install a 3 A fused jumper wire between the signal circuit terminal 13 and ground. Verify the scan tool Central Door Lock Switch on Center Console parameter is Unlock.
• If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
6. If all circuits test normal, replace the A20 radio/HVAC control.
Door Lock Malfunction
1. Ignition OFF, disconnect the harness connector at the A23 door latch assembly.
2. Connect a test lamp between the control circuit terminals listed below:
* A23D door latch assembly-driver terminal 2 and terminal 3
* A23P door latch assembly-passenger terminal 7 and terminal 8
* A23LR door latch assembly-left rear terminal 2 and terminal 3
* A23RR door latch assembly-right rear terminal 7 and terminal 8
3. Ignition ON, command the door to LOCK and UNLOCK by using the central door lock switch. 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 an open/high resistance.
4. If all circuits test normal, test or replace the A23 door latch assembly.
All Door Locks Inoperative
1. Ignition OFF, disconnect the X6 harness connector at the K9 BCM.
2. Disconnect the X2 and X4 harness connectors at the X50D fuse block-underhood.
3. Test for infinite resistance between the control circuit listed below and ground:
* Connector X2, terminal K8 at the X50D fuse block-underhood
* Connector X4, terminal A7 at the X50D fuse block-underhood
* Connector X6 terminal 2 at the K9 BCM
* Connector X6 terminal 1 at the K9 BCM
• If not the specified value, test the appropriate control circuit for a short to ground. If the circuit tests normal, test or replace the appropriate A23 door latch assembly.
4. Connect the X4 harness connector at the X50D fuse block-underhood.
5. Test for infinite resistance between the control circuit terminal 4 at the K9 BCM and ground.
• If not the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the X50D fuse block-underhood.
6. If all circuits test normal, replace the K9 BCM.
Component Testing
Door Latch
1. Ignition OFF, disconnect the harness connector at the appropriate A23 door latch assembly.
2. Install a 25 A fused jumper wire between one of the control terminals and 12 V. 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 and UNLOCK functions.
• If it does not perform as specified, replace the A23 door latch assembly.
Central Door Lock Switch
1. Ignition OFF, disconnect the harness connector at the A20 radio/HVAC control.
2. Test for infinite resistance between the signal terminal 12 and the ground terminal 17 with the switch in the open position.
• If not the specified value, replace the A20 radio/HVAC control.
3. Test for infinite resistance between the signal terminal 13 and the ground terminal 17 with the switch in the open position.
• If not the specified value, replace the A20 radio/HVAC control.
4. Test for less than 2 ohm between the signal terminal 12 and the ground terminal A17 with the switch in the lock position.
• If greater than the specified range, replace the A20 radio/HVAC control.
5. Test for less than 2 ohm between the signal terminal 13 and the ground terminal A with the switch in the unlock position.
• If greater than the specified range, replace the A20 radio/HVAC control
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the repair.
* Front Side Door Latch Replacement (Service and Repair)
* Rear Side Door Latch Replacement (Service and Repair)
* Accessory Wiring Junction Block Replacement (Accessory Wiring Junction Block Replacement)
* Control Module References (Programming and Relearning) BCM and HVAC control replacement, setup and programming