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) provides battery positive voltage and ground to the appropriate lock and unlock control circuits of the door lock and unlock relays. The lock control circuits of the driver and passenger door latch assemblies share a common relay; however, the unlock control circuits have separate relays. The system is designed this way so that the keyless entry transmitter may be used to unlock only the driver door.
The BCM supplies and monitors a reference voltage to the door lock/window switch through the door lock switch lock and unlock signal circuits. The door lock/window switch also receives a constant ground source. If a door lock switch is placed in the lock position or unlock position, the reference voltage is taken directly to ground and the BCM detects the voltage drop on the signal circuit.
The BCM, upon receipt of a lock switch lock signal, will switch the all lock relay control circuit to battery positive voltage. This will energize the relay. The relay will supply voltage to the door lock actuator lock control circuits to one side of the lock actuator. Since the opposing side of the lock actuators are connected to ground through the other lock actuator control circuit and the normally closed contacts of the lock or unlock relay, the doors will then lock appropriately. The remaining unlock relays receive voltage from the I/P fuse block, the BCM upon receipt of a unlock signal or driver door unlock signal will switch the appropriate unlock relay to ground. This will energize the appropriate unlock relay. The relay will supply voltage to the appropriate door unlock control circuits to one side of the lock actuator. Since the opposing side of the lock actuators are connected to ground through the other lock actuator control circuits and the normally closed contact of the lock relay, the doors will then unlock appropriately.
Reference Information
Schematic Reference
Door Lock/Indicator Schematics Door Lock/Indicator Schematics
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
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
1. Ignition ON, observe the scan tool Driver Door Lock Sw and Driver Door Unlock Sw parameters while using the door lock/window switch. The parameter should change between Inactive and Active.
• If the value does not change, refer to Door Lock Switch Malfunction
2. Command the driver and passenger doors to LOCK and UNLOCK by using the door lock/window switch. All doors should LOCK and UNLOCK while changing between the commanded states.
• If the driver door or passenger does not LOCK or UNLOCK, refer to Driver Or Passenger Door Lock Malfunction.
• If the left rear or right rear doors do not LOCK or UNLOCK refer to Rear Door Lock Malfunction
• If all doors do not LOCK and UNLOCK, refer to All Door Locks Inoperative
Circuit/System Testing
Door Lock Switch Malfunction
1. Ignition OFF, disconnect the X2 harness connector at the S101 door lock/window switch.
2. Test for less than 10 ohms between the ground circuit terminal 4 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Driver Door Lock Sw parameter is Inactive.
• If not the specified value, test the signal circuit terminal 15 for a short to ground. If the circuit tests normal, replace the K9 body control module.
4. Install a 3 A fused jumper wire between the signal circuit terminal 15 and ground. Verify the scan tool Driver Door Lock Sw parameter is Active.
• 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 body control module.
5. Verify the scan tool Driver Door Unlock Sw parameter is Inactive.
• If not the specified value, test the signal circuit terminal 5 for a short to ground. If the circuit tests normal, replace the K9 body control module.
6. Install a 3A fused jumper wire between the signal circuit terminal 5 and ground. Verify the scan tool Driver Door Unlock Sw parameter is Active.
• 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 body control module.
7. If all circuits test normal, test or replace the S101 door lock/window switch.
Driver Or Passenger Door Lock Malfunction
1. Ignition OFF, disconnect the KR92D driver door unlatch relay.
2. Test for less than 10 ohms between the ground circuit terminal 87A and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Verify that a test lamp illuminates between the B+ circuit terminal 86 and ground.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, refer to All Door Locks Inoperative.
4. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 30 and ground.
• If the test lamp illuminates, test the control circuit for a short to voltage.
5. Connect a test lamp between the control circuit terminal 85 and the B+ circuit terminal 86.
6. Command the driver and passenger door to UNLOCK by using the S101 door lock/window switch. The test lamp should illuminate during the UNLOCK command.
• If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 body control module.
• If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K9 BCM.
7. Ignition OFF, connect the KR92D driver door unlatch relay.
8. Disconnect the harness connector at the appropriate driver or passenger A23 door latch assembly.
9. Connect a test lamp between the control circuit terminal listed below and ground.
* A23D door latch assembly-driver control circuit terminal 2
* A23P door latch assembly-passenger control circuit terminal 7
10. Ignition ON, command the door to UNLOCK by using the S101 door lock/window switch. The test lamp should briefly illuminate when commanding the UNLOCK states.
• 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, test or replace the KR92D driver door unlatch relay.
11. Connect a test lamp between the control circuit terminal listed below and ground.
* A23D door latch assembly-driver control circuit terminal 3
* A23P door latch assembly-passenger control circuit terminal 8
12. Command the door to LOCK by using the S101 door lock/window switch. The test lamp should briefly illuminate when commanding the LOCK states.
• If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance.
13. If all circuits test normal, test or replace the driver or passenger A23 door latch assembly.
Rear Door Lock Malfunction
1. Ignition OFF, disconnect the KR92P passenger door unlatch relay.
2. Test for less than 10 ohms between the ground circuit terminal 87A and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Verify that a test lamp illuminates between the B+ circuit terminal 86 and ground.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, refer to All Door Locks Inoperative
4. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 30 and ground.
• If the test lamp illuminates, test the control circuit for a short to voltage.
5. Connect a test lamp between the control circuit terminal 85 and the B+ circuit terminal 86.
6. Command the rear doors to UNLOCK by using the S101 door lock/window switch. The test lamp should illuminate during the UNLOCK command.
• If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 body control module.
• If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K9 BCM.
7. Ignition OFF, connect the KR92P passenger door unlatch relay and disconnect the harness connector at the appropriate rear A23 door latch assembly.
8. Connect a test lamp between the control circuit terminal listed below and ground.
* A23LR door latch assembly-left rear control circuit terminal 2
* A23RR door latch assembly-right rear control circuit terminal 5
9. Ignition ON, command the rear door to UNLOCK by using the S101 door lock/window switch. The test lamp should briefly illuminate when commanding the UNLOCK states.
• 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, test or replace the KR92P passenger door unlatch relay.
10. Connect a test lamp between the control circuit terminal listed below and ground.
* A23LR door latch assembly-left rear control circuit terminal 3
* A23RR door latch assembly-right rear control circuit terminal 6
11. Command the rear doors to LOCK by using the S101 door lock/window switch. The test lamp should briefly illuminate when commanding the LOCK states.
• If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance.
12. If all circuits test normal, test or replace the rear A23 door latch assembly.
All Door Locks Inoperative
1. Ignition OFF, disconnect the KR97 door lock relay.
2. Test for less than 10 ohms between the ground circuit terminal 87A and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Test for less than 10 ohms between the ground circuit terminal 85 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
4. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 87 and ground.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
5. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 30 and ground.
• If the test lamp illuminates, test the control circuit for a short to voltage.
6. Connect a test lamp between the control circuit terminal 86 and the ground circuit terminal 85.
7. Command the doors to LOCK by using the S101 door lock/window switch. The test lamp should briefly illuminate during the LOCK command.
• 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 K9 body control module.
• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 body control module.
8. Ignition OFF, disconnect the KR92D driver door unlatch relay and the KR92P passenger door unlatch relay.
9. Test infinite resistance between the control circuit terminal listed below and ground:
* KR92D driver door unlatch relay control circuit terminal 30
* KR92P passenger door unlatch relay control circuit terminal 30
* KR97 door lock relay control circuit terminal 30
• If not the specified value, test the control circuit for a short to ground. If the circuits test normal, test or replace the appropriate KR92D driver door unlatch relay, KR92P passenger door unlatch relay or KR97 door lock relay.
10. If all circuits test normal, test or replace the K9 body control module.
Component Testing
Door Lock Window/Switch Test
1. Ignition OFF, disconnect the X2 harness connector at the door lock/window switch.
2. Test for infinite resistance between the signal terminals 5 and 15 and the ground terminal 4 with the switch in the open position.
• If less than the specified value, replace the door lock/window switch.
3. Test for less than 2 ohms between the signal terminal 15 and the ground terminal 4 with the switch in the lock position.
• If greater than the specified range, replace the door lock/window switch.
4. Test for less than 2 ohms between the signal terminal 5 and the ground terminal 4 with the switch in the unlock position.
• If greater than the specified range, replace the door lock/window switch.
Door Latch Test
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 A23 door latch assembly should perform the LOCK or UNLOCK functions
• If it does not perform as specified, replace the A23 door latch assembly.
Relay Test
1. Ignition OFF, disconnect the appropriate relay.
2. Test for 60 - 200 ohms between terminals 85 and 86.
• If not within the specified range, replace the relay.
3. Test for infinite resistance between the following terminals:
* 30 and 86
* 30 and 87
* 30 and 85
* 85 and 87
• If less than the specified value, replace the relay.
4. Test for less than 2 ohms between terminals 30 and 87A.
• If greater than the specified range, replace the relay.
5. Install a 3 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87.
• If greater than specified range, replace the relay.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Relay Replacement (Within an Electrical Center) Relay Replacement (Within an Electrical Center)Relay Replacement (Attached to Wire Harness) Relay Replacement (Attached to Wire Harness)
* Front Side Door Latch Replacement Service and Repair
* Rear Side Door Latch Replacement Service and Repair
* Door Lock and Side Window and Outside Rearview Mirror Remote Control Switch Replacement (9C1) Door Lock and Side Window and Outside Rearview Mirror Remote Control Switch Replacement (9C1)
* Door Lock and Side Window Switch Replacement - Passenger Side (9C1) Door Lock and Side Window Switch Replacement - Passenger Side (9C1)
* Front Side Door Window, Rear Side Door Window, and Multifunction Switch Replacement (9C3) Front Side Door Window, Rear Side Door Window, and Multifunction Switch Replacement (9C3)
* Control Module References Control Module References for BCM replacement, programming and setup