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) powers the reversible door latch assemblies by providing battery positive voltage and ground to the appropriate lock and unlock control circuits of the door latch assemblies. The lock and unlock control circuits of the rear doors and passenger door latch assemblies are all connected together. When the door latch assemblies are not active, all actuator lock and unlock control circuits are at ground potential within the BCM. Transitioning of the lock actuators to the lock or unlocked position depends upon which control circuits receive voltage and which control circuits receive ground.
Reference Information
Schematic Reference
Door Lock/Indicator Schematics (Door Lock/Indicator Schematics)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
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 (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 on the S48C multifunction switch 1-instrument panel.
• If the value does not change between commanded states, refer to Central Door Lock Switch Malfunction.
2. Command the doors to LOCK and UNLOCK with a scan tool, all doors should LOCK and UNLOCK while 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 S48C multifunction switch 1-instrument panel.
2. Test for less than 10 ohm between the ground circuit terminal 7 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 11 for a short to ground. If the circuit tests normal, replace the K9 BCM.
• If the value is Unlock , test the signal circuit terminal 9 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 11 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 9 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 S48C multifunction switch 1-instrument panel.
Door Lock Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate 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 for either the LOCK or UNLOCK command, test the control circuit for an open/high resistance between the connector and the circuit splice.
4. If all circuits test normal, test or replace the A23 door latch assembly.
All Door Locks Inoperative
1. Ignition OFF, disconnect the X2 harness connector at the K9 BCM.
2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 4 and ground.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
3. Ignition OFF, connect the X2 harness connector and disconnect the X6 harness connector at the K9 BCM.
4. Test for infinite resistance between the control circuit listed below and ground:
* Control circuit terminal 1
* Control circuit terminal 2
* Control circuit terminal 4
• 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.
5. 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 S48C multifunction switch 1-instrument panel.
2. Test for infinite resistance between the signal terminal 11 and the ground terminal 7 with the switch in the open position.
• If not the specified value, replace the S48C multifunction switch 1-instrument panel.
3. Test for infinite resistance between the signal terminal 9 and the ground terminal 7 with the switch in the open position.
• If not the specified value, replace the S48C multifunction switch 1-instrument panel.
4. Test for less than 2 ohm between the signal terminal 11 and the ground terminal 7 with the switch in the lock position.
• If greater than the specified range, replace the S48C multifunction switch 1-instrument panel.
5. Test for less than 2 ohm between the signal terminal 9 and the ground terminal 7 with the switch in the unlock position.
• If greater than the specified range, replace the S48C multifunction switch 1-instrument panel.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Hazard Warning Switch Replacement (Service and Repair)
* Front Side Door Lock Replacement (Front Side Door Lock Replacement)
* Rear Side Door Lock Replacement (Rear Side Door Lock Replacement)
* Control Module References (Programming and Relearning) for BCM replacement, setup and programming