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 Unlock Signal | 1 | 1 | 1 | -- |
Driver Door Lock Ground | -- | 1 | 1 | -- |
1. Key Cylinder Switch Malfunction | ||||
Circuit/System Description
The key cylinder unlock feature will unlock all of the doors when the body control module (BCM) receives a Door Lock Key Switch Unlock signal for greater than 1 second and will unlock 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 driver door lock cylinder, turn the key the unlock position and hold for greater than 1 second while observing the scan tool Door Key Cyl Unlock Switch parameter. The parameter should change between Active and Inactive.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the driver door lock.
- Test for less than 1 ohm between the ground circuit terminal 8 and ground.
- Ignition ON, verify the scan tool Door Key Cyl Unlock Switch parameter is Inactive.
- Install a 3-amp fused jumper wire between the signal circuit terminal 9 and ground, verify the scan tool Door Key Cyl Unlock Switch parameter is Active.
- If all circuits test normal, test or replace the driver door lock.
| ⇒ | 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 lock.
- Test for infinite resistance between the signal terminal 9 and the ground terminal 8 with the switch in the open position.
- Test for less than 2 ohms between the signal terminal 9 and the ground terminal 8 with the switch in the Unlock position.
| ⇒ | If not the specified value, replace the driver door lock. |
| ⇒ | If greater than the specified range, replace the driver door lock. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
