Power Door Lock Key Cylinder Switches Inoperative

Power Door Lock Key Cylinder Switches Inoperative

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 key cylinder unlock feature will unlock the driver door only with a single turn to the unlock position and all of the doors when the driver door switch (DDS) receives two consecutive turns to the unlock position and will send a request to the passenger door switch (PDS) and the BCM to unlock all of the doors.

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 (Control Module References) for scan tool information

Circuit/System Verification

Ignition ON, insert the key into the driver's door lock cylinder and observe the scan tool Door Key Cyl. Unlock Switch parameter while turning the key to the UNLOCK position, the parameter should change between Idle and Unlock.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the driver door latch.
2. Test for less than 1 ohm between the low reference circuit terminal 8 and ground.

• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the DDM

3. Ignition ON, verify the scan tool Door Key Cyl Unlock Switch parameter is Idle.

• If not the specified value, test the signal circuit terminal 9 for a short to ground. If the circuits test normal, replace the DDM.

4. Install a 3A fused jumper wire between the signal circuit terminal 9 and ground, verify the scan tool Door Key Cyl Unlock Switch parameter is Unlock.

• If not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the DDM.

5. If all circuits tests normal, test or replace the driver door latch.

Component Testing

1. Ignition OFF, disconnect the harness connector at the driver door latch.
2. Test for infinite resistance between the signal terminal 9 and the low reference terminal 8 with the switch in the open position.

• If not the specified value, replace the driver door latch.

3. Test for less than 2 ohms between the signal terminal 9 and the low reference terminal 8 with the switch in the Unlock position.

• If greater than the specified range, replace the driver door latch.

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 (Control Module References) for DDM replacement, setup, and programming