Power Door Lock Key Cylinder Switches Inoperative
Power Door Lock Key Cylinder Switches Inoperative
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 each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The key cylinder lock/unlock feature will unlock or lock all of the doors when the body control module (BCM) receives a Door Lock Key Switch Unlock or Lock signal for greater than 1 second and will unlock or lock all of the doors.
Reference Information
Schematic Reference
Door Lock/Indicator Schematics (Door Lock/Indicator Diagrams)
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 function of the door locks while performing the LOCK and UNLOCK command using a scan tool, all doors should the LOCK and UNLOCK.
• If any door fails to LOCK or UNLOCK, refer to Power Door Locks Inoperative (Power Door Locks Inoperative).
2. Observe the scan tool LF Key Cylinder Lock Switch parameters while the turning and holding the key in the driver door lock cylinder to the left and then to the right, reading should change from Idle to Lock and Unlock.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the driver door lock.
2. Ignition OFF, test for less than 1.0 ohm between the ground circuit terminal 8 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool LF Key Cylinder Lock Switch parameter is Idle.
• If not the specified value, test the signal circuit terminal 9 or signal circuit terminal 4 for a short to ground. If the circuits test normal, replace the BCM.
4. Install a 3-amp fused jumper wire between the signal circuit terminal 4 and ground, verify the scan tool LF Key Cylinder Lock Switch 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 BCM.
5. Install a 3-amp fused jumper wire between the signal circuit terminal 9 and ground, verify the scan tool LF Key Cylinder Lock Switch 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 BCM.
6. If all circuits tests normal, test or replace the driver door lock.
Component Testing
1. Ignition OFF, disconnect the harness connector at the driver door lock.
2. Test for infinite resistance between the signal terminal 9 and the ground terminal 8 with the switch in the Idle position.
• If not the specified value, replace the driver door lock.
3. Test for infinite resistance between the signal terminal 4 and the ground terminal 8 with the switch in the Idle position.
• If not the specified value, replace the driver door lock.
4. Test for less than 2.0 ohms between the signal terminal 9 and the ground terminal 8 with the switch in the Unlock position.
• If greater than the specified range, replace the driver door lock.
5. Test for less than 2.0 ohms between the signal terminal 4 and the ground terminal 8 with the switch in the Lock position.
• If greater than the specified range, replace the driver door lock.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Front Side Door Lock Replacement (Front Side Door Lock Replacement)
* Control Module References (Programming and Relearning) for BCM replacement, setup and programming