Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Driver Door Key Switch Signal | 1 | 1 | 1 | -- |
Driver Door Latch Ground | -- | 1 | 1 | -- |
1. Key Cylinder Switch Inoperative | ||||
Circuit/System Description
The key cylinder unlock feature will unlock or lock all of the doors when the body control module (BCM) receives a Key Unlock Switch or an Key Lock Switch signal for greater than 1 second and will unlock or lock all of the doors.
Reference Information
Schematic Reference
Door Lock/Indicator Schematics
Connector End View Reference
Description and Operation
Power Door Locks Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Ignition ON, insert the key into the drivers door lock cylinder, turn the key to the LOCK position and turn the key to the UNLOCK position while observing the scan tool Door Cylinder Switch parameter, the parameter should change from Idle to Lock and Unlock.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the driver door latch.
- Test for less than 5 ohms between the ground circuit terminal 8 and ground.
- Ignition ON, verify the scan tool Door Cylinder Switch parameter is Idle.
- Install a 3A fused jumper wire between the signal circuit terminal 9 and ground. Verify the scan tool Door Cylinder Switch parameter is Lock.
- If all circuits test normal, test or replace the driver door latch.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| ⇒ | If not the specified value, test the signal circuit terminal 9 for a short to ground. If the circuit tests normal, replace the BCM. |
| ⇒ | 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. |
Component Testing
- Ignition OFF, disconnect the harness connector at the driver door latch.
- Test for infinite resistance between the signal terminal 9 and the ground terminal 8 with the switch in the open position.
- Test for 450-550 ohms between the signal terminal 9 and the ground terminal 8 with the switch in the unlock position.
- Test for less than 2 ohms between the signal terminal 9 and the ground terminal 8 with the switch in the lock position.
| ⇒ | If not the specified value, replace the driver door latch. |
| ⇒ | If not the specified range, replace the driver door latch. |
| ⇒ | If greater than the specified range, replace the driver door latch. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup and programming |
