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Power Door Locks Inoperative



POWER DOOR LOCKS INOPERATIVE

DIAGNOSTIC INSTRUCTIONS
- Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
- 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/SYSTEM DESCRIPTION

DRIVER DOOR LOCK AND UNLOCK OPERATION
The driver door lock switch lock and unlock signal circuits provide input to the driver door switch assembly (DDSA) when the driver door lock switch is activated to the Lock or Unlock position. These inputs allow the DDSA to detect a door lock or unlock request. The DDSA provides power to the driver door lock switch. When the driver door lock switch is activated, ground is supplied by G201. When the DDSA detects low voltage on a signal circuit, the DDSA will send a message on the serial data line to the remote control door lock receiver (RCDLR) to place the driver and passenger doors in lock or unlock status, disabling or enabling the power door latch.

PASSENGER DOOR LOCK AND UNLOCK OPERATION
The passenger door lock switch lock and unlock signal circuits provide input to the passenger door module (PDM) when the passenger door lock switch is activated to the Lock or Unlock position. These inputs allow the PDM to detect a door lock or unlock request. The PDM provides power to the passenger door lock switch. When the passenger door lock switch is activated, ground is supplied by G202. When the PDM detects low voltage on a signal circuit, the PDM will send a message on the serial data line to the remote control door lock receiver (RCDLR) to place the driver and passenger doors in lock or unlock status, disabling or enabling the power door latch.

CIRCUIT/SYSTEM VERIFICATION
1. Ignition ON, observe the scan tool LF Door Open Switch parameter located in Theft Data while opening and closing the driver door. The reading should toggle between DOOR OPEN and KEY OFF.
- If the reading does not change between the commanded states, refer to Automatic Door Locks Malfunction.
2. Observe the scan tool RF door open switch parameter located in Theft Data while opening and closing the passenger door. The reading should toggle between DOOR OPEN and KEY OFF.
- If the reading does not change between the commanded states, refer to Automatic Door Locks Malfunction.

CIRCUIT/SYSTEM TESTING

Door Locks Inoperative from Driver Switch
1. Ignition OFF, disconnect the harness connector at the driver door lock switch.
2. Test for less than 1 ohm of resistance between the ground circuit terminal C and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Door Lock Switch parameter is IDLE.
- If the scan tool displays LOCK, test the signal circuit terminal D for a short to ground. If the circuit tests normal, replace the DDSA.
- If the scan tool displays UNLOCK, test the signal circuit terminal E for a short to ground. If the circuit tests normal, replace the DDSA.
4. Install a 3A fused jumper wire between the signal circuit terminal D and ground. Verify the scan tool Door Lock Switch parameter is LOCK.
- If not the specified value, test the signal circuit terminal D for a short to voltage or an open/high resistance. If the circuit tests normal, replace the DDSA.
5. Install a 3A fused jumper wire between the signal circuit terminal E and ground. Verify the scan tool Door Lock Switch parameter is UNLOCK.
- If not the specified value, test the signal circuit terminal E for a short to voltage or an open/high resistance. If the circuit tests normal, replace the DDSA.
6. If all circuits test normal, test or replace the driver door lock switch.

DOOR LOCK INOPERATIVE FROM PASSENGER SWITCH
1. Ignition OFF, disconnect the harness connector at the passenger door lock switch.
2. Test for less than 1 ohm of resistance between the ground circuit terminal C and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Door Lock Switch parameter is IDLE.
- If the scan tool displays LOCK, test the signal circuit terminal D for a short to ground. If the circuit tests normal, replace the PDM.
- If the scan tool displays UNLOCK, test the signal circuit terminal E for a short to ground. If the circuit tests normal, replace the PDM.
4. Install a 3A fused jumper wire between the signal circuit terminal D and ground. Verify the scan tool Door Lock Switch parameter is LOCK.
- If not the specified value, test the signal circuit terminal D for a short to voltage or an open/high resistance. If the circuit tests normal, replace the PDM.
5. Install a 3A fused jumper wire between the signal circuit terminal E and ground. Verify the scan tool Door Lock Switch parameter is UNLOCK.
- If not the specified value, test the signal circuit terminal E for a short to voltage or an open/high resistance. If the circuit tests normal, replace the PDM.
6. If all circuits test normal, test or replace the passenger door lock switch.

AUTOMATIC DOOR LOCKS INOPERATIVE
1. Ignition OFF, disconnect the harness connector at the inoperative door latch assembly.
2. Test for less than 1 ohm of resistance between the ground circuit and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool door open switch parameter is KEY OFF.
- If the scan tool displays DOOR OPEN, test the signal circuit for a short to ground. If the circuit tests normal, replace the BCM.
4. Install a 3A fused jumper wire between the signal circuit and ground. Verify the scan tool door open switch parameter is DOOR OPEN.
- 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. If all circuits test normal, test or replace the inoperative door latch assembly.

REPAIR INSTRUCTIONS
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

- Door Lock Replacement
- Door Latch Release Switch Replacement - Driver Side
- Door Latch Release Switch Replacement - Passenger Side
- Door Lock Switch Replacement - Driver Door
- Door Lock Switch Replacement - Passenger Front
- Control Module References for BCM, DDSA or PDM replacement, setup, and programming. Programming and Relearning
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