The driver and front passenger power door lock switches are integral components of the driver door module (DDM) and passenger door module (PDM). The switches consist of 2 positions, lock and unlock, and are in the normally open state. When placed in either the lock or unlock positions, the switches provide a direct input to their respective door control module. When a power door lock switch is operated to the lock or unlock position, the associated door control module responds by sending a serial data message indicating a change in the switch's position. This serial data message is received by the opposite door control module as well as the body control module (BCM). The DDM and PDM respond to the lock/unlock request by activating their associated power door lock motors to the appropriate direction to lock or unlock the front doors. The BCM is responsible for controlling the left and right rear passenger door lock motors. The BCM, upon receipt of a lock or unlock serial data signal, will control either the rear door lock or unlock relay. When the appropriate door lock relay is energized, the rear power door lock motors will lock or unlock the rear doors.

Schematic Reference

Door Lock/Indicator Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Power Door Locks Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Ignition ON, command the doors to LOCK and UNLOCK by using the driver and passenger door lock switches, the doors should perform the LOCK and UNLOCK functions from both switches.

DDM/PDM Malfunction

1. Ignition OFF, disconnect the X1 harness connector at the appropriate door module.
2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 4 and ground.

⇒	If the test lamp does not illuminate, test the B+ circuit for a short to ground or open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, replace the door module.

3. Ignition OFF, connect the X1 harness connector at the door module and disconnect the harness connector at the door latch.
4. Ignition ON, test for less than 5 ohms between the control circuit terminal listed below and ground.

•	Driver door latch terminal 2

•	Driver door latch terminal 3

•	Passenger door latch terminal 5

•	Passenger door latch terminal 6

⇒	If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the door module.

5. Connect a test lamp between control circuit terminals listed below:

•	Driver door latch terminal 2 and 3

•	Passenger door latch terminal 5 and 6

6. Command the door latch to LOCK and UNLOCK by using the door lock switch. The test lamp should briefly illuminate when commanding the LOCK and UNLOCK states.

⇒	If the test lamp is always OFF during either of the commands, test either control circuit for a short to ground. If the circuits test normal, replace the door module.

7. If all circuits test normal, test or replace the door latch.

Rear Door Lock Malfunction

1. Ignition OFF, disconnect the UNLOCK relay.
2. Test for less than 20 ohms between the ground circuit terminal 87A and ground.

⇒	If greater than the specified range, test the ground circuit for a short to voltage or an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal listed below and ground:

•	Terminal 86

•	Terminal 87

⇒	If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance

4. Connect a test lamp between the B+ circuit terminal 86 and the control circuit terminal 85.
5. Command the doors to UNLOCK with a scan tool. The test lamp should briefly illuminate during the UNLOCK command.

⇒	If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

⇒	If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.

6. Ignition OFF, connect the UNLOCK relay and disconnect the LOCK relay.
7. Test for less than 20 ohms between the ground circuit terminals listed below and ground:

•	Terminal 86

•	Terminal 87A

⇒	If greater than the specified range, test the ground circuit for a short to voltage or an open/high resistance.

8. Connect a test lamp between the ground circuit terminal 86 and the control circuit terminal 85.
9. Command the doors to LOCK with a scan tool. The test lamp should briefly illuminate during the LOCK command.

⇒	If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

⇒	If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.

10. Ignition OFF, connect the LOCK relay and disconnect the harness connector at the appropriate rear door latch.
11. Test for less than 20 ohms between the control circuit terminal listed below and ground:

•	LR door latch terminal 2

•	RR door latch terminal 5

⇒	If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the UNLOCK relay.

12. Test for less than 20 ohms between the control circuit terminal listed below and ground:

•	LR door latch terminal 3

•	RR door latch terminal 6

⇒	If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the LOCK relay.

13. Connect a test lamp between the control circuit terminal listed below and ground:

•	LR door latch terminal 2

•	RR door latch terminal 5

14. Command the doors to UNLOCK with a scan tool. The test lamp should briefly illuminate during the UNLOCK command.

⇒	If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the UNLOCK relay.

⇒	If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, test or replace the UNLOCK relay.

15. Connect a test lamp between the control circuit terminal listed below and ground:

•	LR door latch terminal 3

•	RR door latch terminal 6

16. Command the doors to LOCK with a scan tool. The test lamp should briefly illuminate during the LOCK command.

⇒	If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the LOCK relay.

⇒	If the test lamp is always ON, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the LCK relay.

17. If all circuits test normal, test or replace the rear door latch.

Relay Test

1. Ignition OFF, disconnect the appropriate relay.
2. Test for 60-180 ohms between terminals 85 and 86.

⇒	If not within the specified range, replace the relay.

3. Test for infinite resistance between the following terminals:

•

30 and 86

•

30 and 87

•

30 and 85

•

85 and 87

⇒	If not the specified value, replace the relay.

4. Test for less than 2 ohms between terminals 30 and 87A.

⇒	If greater than the specified value, replace the relay.

5. Install a 25A fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87.

⇒	If greater than the specified value, replace the relay.

Door Latch Assembly Test

1. Ignition OFF, disconnect the harness connector at the appropriate door latch.
2. Install a 20A fused jumper wire between one of the control terminals and 12V. Momentarily install a jumper wire between the other control terminal and ground. Reverse the jumper wires at least two times, the door latch should perform the LOCK/ UNLOCK functions.

⇒	If it does not perform as specified, replace the door latch

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.