Diagnostic Instructions
Circuit/System Description
Except RPO AXC/AXA
The key cylinder unlock feature will unlock all of the doors when the body control module (BCM) receives a Key Unlock Switch signal for greater than 1 second and will unlock all of the doors.
RPO AXC/AXA
The key cylinder unlock feature will unlock all of the doors when the driver door module (DDM) receives a Key Unlock Switch signal for greater than 1 second and will send a request to the passenger door module (PDM) and the BCM to unlock all of
the doors.
Reference Information
Schematic Reference
Door Lock/Indicator Schematics
Connector End View Reference
Vehicle Access Connector End Views
Description and Operation
Power Door Locks Description and Operation
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
Ignition OFF, insert the key into the driver’s door lock cylinder, turn the key clockwise and hold for greater than 1 second and turn the key counterclockwise and hold for greater than 1 second while observing the scan tool Door Key Cyl Unlock
Switch parameters, the reading should change between Active and Inactive.
Circuit/System Testing
Except RPO AXC/AXE
- Ignition OFF, disconnect the harness connector at the driver door latch assembly.
- 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. |
- Ignition ON, verify the scan tool Door Key Cyl Unlock Switch parameter is Inactive.
⇒ | If not the specified value, test the signal circuit terminal 9 for a short to ground. If the circuits test normal, replace the BCM. |
- 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 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. |
- If all circuits tests normal, test or replace the driver door latch assembly.
With RPO AXC/AXE
- Ignition OFF, disconnect the harness connector at the driver door latch assembly.
- Ignition ON, verify the scan tool Door Key Cyl Unlock Switch parameter is Inactive.
⇒ | If not the specified value, test the signal circuit terminal 9 for a short to ground. If the circuits test normal, replace the DDM. |
- 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 not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the DDM. |
- Install a 3-amp fused jumper wire between the signal circuit terminal 9 and the low reference circuit terminal 8, verify the scan tool Door Key Cyl Unlock Switch parameter is Active.
⇒ | If not the specified value, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the DDM. |
- If all circuits tests normal, test or replace the driver door latch assembly.
Component Testing
- Ignition OFF, disconnect the harness connector at the driver door latch assembly.
- Test for infinite resistance between the signal terminal 9 and the ground terminal 8 with the switch in the open position.
⇒ | If not the specified value, replace the driver door latch assembly. |
- 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 latch assembly. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.