The driver and front passenger power door lock switches are integral components of the driver door switch (DDS) and passenger door switch (PDS). 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 there 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 switches position. This serial data message is received by the opposite door control module as well as the body control module (BCM) and the liftgate module (LGM). The DDS, PDS and LGM respond to the lock/unlock request by activating there 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

1. Ignition ON, command the front doors to LOCK and UNLOCK by using the driver and passenger door lock switches, the doors should perform LOCK and UNLOCK function from each switch.

⇒	If the driver door does not LOCK or UNLOCK, refer to Driver Door Lock Malfunction.

⇒	If the passenger door does not LOCK or UNLOCK, refer to Passenger Door Lock Malfunction.

2. Command the rear doors to LOCK and UNLOCK with a scan tool, the rear doors should perform the LOCK and UNLOCK function.

⇒	If a rear door does not LOCK or UNLOCK, refer to Rear Door Lock Malfunction.

3. Command the liftgate to LOCK and UNLOCK with a scan tool, the liftgate should perform LOCK and UNLOCK function

⇒	If the liftgate does not LOCK or UNLOCK, refer to Liftgate Lock Malfunction.

Driver Door Lock Malfunction

1. Ignition OFF, disconnect the X1 harness connector at the DDS.
2. Test for less than 1 ohm between the ground circuit terminal A and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

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

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

4. Ignition OFF, connect the X1 harness connector and disconnect the X2 harness connector at the DDS.
5. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal B5 and ground.

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

6. Ignition OFF, connect the X2 harness connector at the DDS and disconnect the harness connector at the driver door latch.
7. Test for less than 2 ohms between the control circuit terminal A and ground.

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

8. Test for less than 2 ohms between the control circuit terminal B and ground.

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

9. Ignition ON, connect a test lamp between the control circuit terminal A and control circuit terminal B.
10. Command the door to LOCK and UNLOCK by using the driver 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 DDS.

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

Passenger Door Lock Malfunction

1. Ignition OFF, disconnect the X1 harness connector at the PDS.
2. Test for less than 1 ohm between the ground circuit terminal A and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

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

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

4. Ignition OFF, connect the X1 harness connector and disconnect the X2 harness connector at the PDS.
5. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal B5 and ground.

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

6. Ignition OFF, connect the X2 harness connector at the PDS and disconnect the harness connector at the passenger door latch.
7. Test for less than 2 ohms between the control circuit terminal A and ground.

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

8. Test for less than 2  ohms between the control circuit terminal B and ground.

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

9. Ignition ON, connect a test lamp between the control circuit terminal A and control circuit terminal B.
10. Command the door to LOCK and UNLOCK by using the passenger 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 PDS.

11. If the circuits test normal, test or replace the passenger 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:

•	B+ terminal 86

•	B+ 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 terminal 87A and ground.

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

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

•	B+ terminal 86

•	B+ terminal 87

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

9. Connect a test lamp between the B+ circuit terminal 86 and the control circuit terminal 85.
10. 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, 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.

11. Connect the LOCK relay and disconnect the harness connector at the appropriate rear door latch.
12. Test for less than 20 ohms between the control circuit terminal A and ground.

⇒	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.

13. Test for less than 20 ohms between the control circuit terminal B and ground.

⇒	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.

14. Connect a test lamp between the control circuit terminal A and ground.
15. 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 ground. If the circuit tests normal, test or replace the UNLOCK relay.

16. Connect a test lamp between the control circuit terminal B and ground.
17. 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. If the circuit tests normal, test or replace the LOCK relay.

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

Liftgate Lock Malfunction

1. Ignition OFF, disconnect the X2 harness connector at the liftgate latch assembly.
2. Connect a test lamp between control circuit terminal A and control circuit terminal B.
3. Ignition ON, command the liftgate to LOCK and UNLOCK with a scan tool. The test lamp should illuminate while commanding the LOCK and UNLOCK states.

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

⇒	If the test lamp remains OFF, test either control circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the LGM.

4. If all circuits test normal, test or replace the liftgate latch assembly.

Door Latch Assembly

1. Ignition OFF, disconnect the harness connector at the appropriate door latch.
2. Install a 15A 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

Relay Test

1. Ignition OFF, disconnect the appropriate relay.
2. Test for 60-200 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 less than the specified value, replace the relay.

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

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

5. Install a 3A 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 specified range, replace the relay

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.