Power Door Locks Malfunction
Power Door Locks Malfunction
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (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 the diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The rear fuse block monitors the voltage in the central door lock switch signal circuit, when the central door lock switch is pressed, the voltage drops to 0 and the rear fuse block will apply voltage to the lock relay and ground to the unlock relay, which will cause the door locks to LOCK.
When the door central door lock switch is pressed again, the central door lock switch signal circuit will be open and the voltage will be at or near 9 volts and the rear fuse block will apply voltage to the unlock relay and ground to the lock relay, which will cause the door locks to UNLOCK.
Diagnostic Aids
Verify the driver door is closed, the central door lock switch is disabled when the driver door is in the open or ajar position. If the driver door is closed and the door ajar light is illuminated, refer to Door Ajar Indicator Malfunction (Door Ajar Indicator Malfunction) .
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
1. Ignition ON, observe the scan tool CDLS Switch Status parameter while using the central door lock switch. The parameter should change between Off and On.
• If the parameter does not change, refer to Door Lock Switch Malfunction.
2. Command the door lock indicator ON and OFF with a scan tool, The door lock indicator should turn ON and OFF when changing between the commanded states.
• If the indicator does not illuminate or continuously illuminates, refer to Door Lock Switch Indicator Malfunction.
3. Command the door locks to LOCK and UNLOCK with the scan tool, the all doors should LOCK and UNLOCK.
• If any or all doors do not LOCK and UNLOCK when changing between commanded states, refer to Door Lock Malfunction.
Circuit/System Testing
Door Lock Switch Malfunction
1. Ignition OFF, disconnect the harness connector at the accessory switch assembly.
2. Ignition ON, test for 4.8-5.2 volts between the signal circuit terminal 5 and ground.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the rear fuse block.
• If less than the specified value test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the rear fuse block.
3. If all circuits test normal, test or replace the accessory switch assembly.
Door Lock Switch Indicator Malfunction
1. Ignition OFF, disconnect the harness connector at the accessory switch assembly.
2. Ignition ON, test for greater than 8.5 volts between the control circuit terminal 15 and ground while commanding the door lock indicator ON with a scan tool.
• If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the rear fuse block.
3. Test for less than 1 volt between the control circuit terminal 15 and ground while commanding the door lock indicator OFF with a scan tool.
• If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the rear fuse block.
4. If all circuits test normal, replace the accessory switch assembly.
Door Lock Malfunction
1. Ignition OFF, disconnect the lock and unlock relays.
2. Test for greater than 15 ohms between the control circuit terminal listed below and ground.
* Unlock relay control circuit terminal 2
* Lock relay control circuit terminal 2
• If less than the specified range, test the control circuit for a short to ground. If the circuit tests normal, replace the underhood fuse block.
3. Connect a test lamp between the control circuit terminal listed below and ground.
* Unlock relay control circuit terminal 4
* Lock relay control circuit terminal 4
4. Command the doors to LOCK and UNLOCK with a scan tool, the test lamp should briefly illuminate when changing between the commanded states.
• If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance, if the circuit tests normal, replace the rear fuse block.
• If the test lamp continuously illuminates, test the control circuit for a short to voltage, if the circuit tests normal, replace the rear fuse block.
5. Ignition OFF, connect the lock and unlock relays and disconnect the appropriate door lock.
6. Test for less than 5 ohms between the control circuit terminal listed below and ground:
* Driver door lock control circuit terminal 8
* Passenger door lock control circuit terminal 8
* Left rear door lock control circuit terminal 6
* Right rear door lock control circuit terminal 6
• If greater than the specified range, replace the lock relay.
7. Test for less than 5 ohms between the control circuit terminal 2 and ground.
• If greater than the specified range, replace the unlock relay
8. Ignition ON, connect a test lamp between the control circuit listed below and ground:
* Driver door lock control circuit terminal 8
* Passenger door lock control circuit terminal 8
* Left rear door lock control circuit terminal 6
* Right rear door lock control circuit terminal 6
9. Command the doors to LOCK and UNLOCK with a scan tool, the test lamp should briefly illuminate when changing between the LOCK and UNLOCK states.
• If the test lamp does not illuminate, test the control circuit for an open/high resistance. If the circuit tests normal, replace the lock relay.
• If the test lamp continuously illuminates, test the control circuit for a short to voltage, if the circuit tests normal, test for replace the lock relay.
10. Connect a test lamp between the control circuit terminal 2 and ground.
11. Command the doors to LOCK and UNLOCK with a scan tool, the test lamp should briefly illuminate when changing between the LOCK and UNLOCK states.
• If the test lamp does not illuminate, test the control circuit for an open/high resistance. If the circuit tests normal, replace the unlock relay.
• If the test lamp continuously illuminates, test the control circuit for a short to voltage, if the circuit tests normal, test for replace the unlock relay.
12. If all circuits test normal, test or replace the door lock.
Component Testing
Door Latch Assembly
1. Disconnect the harness connector at the appropriate door lock.
2. Install a 15 amp fused jumper wire between the control terminal listed below and 12 volts.
* Driver door lock control terminal 8
* Passenger door lock control terminal 8
* Left rear door lock control terminal 6
* Right rear door lock control terminal 6
3. Momentarily install a jumper wire between the control terminal 2 and ground. The door lock should perform the LOCK/ UNLOCK function.
• If the function does not perform as specified, replace the door lock.
4. Reverse the jumper wires; the door lock should perform the UNLOCK/LOCK function.
• If the function does not perform as specified, replace the door lock.
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-amp fused jumper wire between the relay terminal 85 and 12 volts. 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 diagnostic procedure.
* Front Side Door Lock Replacement (Front Side Door Lock Replacement)
* Accessory Switch Replacement (Service and 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))
* Rear Door Lock Replacement (Rear Door Lock Replacement)
* Control Module References (Programming and Relearning) for rear fuse block and underhood fuse block replacement, setup, and programming