Operation CHARM: Car repair manuals for everyone.

Symptom Related Diagnostic Procedures






POWER LIFTGATE PEM LOCK SWITCH INOPERATIVE





For a complete wiring diagram, refer to the Wiring Information.

NOTE: This test is used when there is a malfunction with the PEM Lock/Unlock Switch on the License Plate Lamp Bar.






1. PEM LIFTGATE LOCK/UNLOCK CIRCUITS SHORTED TOGETHER




1. Turn the ignition off.
2. Disconnect the Passive Entry Module C1 harness connector.
3. Measure the resistance between the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit and the (P39) PEM Liftgate Lock/Unlock Switch Return circuit in the PEM C1 harness connector.

Is the resistance below 20K Ohms?

Yes

- Go To 2

No

- Go To 3

2. (P39) PEM LIFTGATE LOCK/UNLOCK SWITCH RETURN CIRCUIT SHORTED TO THE (P30) PEM LIFTGATE LOCK/UNLOCK SWITCH SENSE CIRCUIT




1. Disconnect the License Plate Lamp Bar harness connector.
2. Measure the resistance between the (P39) PEM Liftgate Lock/Unlock Switch Return circuit and the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit in the License Plate Lamp Bar harness connector.

Is the resistance below 20K Ohms?

Yes

- Repair the short between the (P39) PEM Liftgate Lock/Unlock Switch Return circuit and the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the License Plate Lamp Bar Assembly. Exterior Handle Lamp Bar - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. PEM LIFTGATE LOCK/UNLOCK CIRCUIT SHORTED TO GROUND




1. Measure the resistance between ground and the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit in the PEM C1 harness connector.
2. Measure the resistance between ground and the (P39) PEM Liftgate Lock/Unlock Switch Return circuit in the PEM C1 harness connector.

Is the resistance below 20K Ohms in either or both circuits?

Yes

- Go To 4

No

- Go To 6

4. (P30) PEM LIFTGATE LOCK/UNLOCK SWITCH SENSE CIRCUIT SHORTED TO GROUND




1. Disconnect the License Plate Lamp Bar harness connector.
2. Measure the resistance between ground and the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit in the License Plate Lamp Bar harness connector.

Is the resistance below 20K Ohms?

Yes

- Repair the short to ground in the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 5

5. (P39) PEM LIFTGATE LOCK/UNLOCK SWITCH RETURN CIRCUIT SHORTED TO GROUND




1. Measure the resistance between ground and the (P39) PEM Liftgate Lock/Unlock Switch Return circuit in the License Plate Lamp Bar harness connector.

Is the resistance below 20K Ohms?

Yes

- Repair the short to ground in the (P39) PEM Liftgate Lock/Unlock Switch Return circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the License Plate Lamp Bar Assembly. Exterior Handle Lamp Bar - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

6. PEM LIFTGATE LOCK/UNLOCK CIRCUIT OPEN




1. Measure the resistance between the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit and the (P39) PEM Liftgate Lock/Unlock Switch Return circuit in the PEM C1 harness connector.
2. While measuring the resistance have a helper press and hold the PEM Liftgate Lock/Unlock switch button.

Is the resistance between 350 and 430 Ohms when the switch is pressed?

Yes

- Go To 9

No

- Go To 7

7. (P30) PEM LIFTGATE LOCK/UNLOCK SWITCH SENSE CIRCUIT OPEN




1. Disconnect the License Plate Lamp Bar harness connector.
2. Measure the resistance of the (P30) PEM Liftgate Lock/Unlock Switch Sense wire between the PEM C1 harness connector and the License Plate Lamp Bar harness connector.

Is the resistance below 2.0 Ohms?

Yes

- Go To 8

No

- Repair the open in the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

8. (P39) PEM LIFTGATE LOCK/UNLOCK SWITCH RETURN CIRCUIT OPEN




1. Measure the resistance of the (P39) PEM Liftgate Lock/Unlock Switch Return circuit between the PEM C1 harness connector and the License Plate Lamp Bar harness connector.

Is the resistance below 2.0 Ohms?

Yes

- Replace the License Plate Lamp Bar Assembly. Exterior Handle Lamp Bar - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Repair the open in the (P39) PEM Liftgate Lock/Unlock Switch Return circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

9. PEM LIFTGATE LOCK/UNLOCK CIRCUIT SHORTED TO VOLTAGE




1. Turn the ignition on.
2. Measure the voltage between ground and the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit in the PEM C1 harness connector.
3. Measure the voltage between ground and the (P39) PEM Liftgate Lock/Unlock Switch Return circuit in the PEM C1 harness connector.

Is there any voltage present in either or both circuits?

Yes

- Go To 10

No

- Go To 12

10. (P39) PEM LIFTGATE LOCK/UNLOCK SWITCH RETURN CIRCUIT SHORTED TO VOLTAGE




1. Disconnect the License Plate Lamp Bar harness connector.
2. Measure the voltage between ground and the (P39) PEM Liftgate Lock/Unlock Switch Return circuit in the License Plate Lamp Bar harness connector.

Is there any voltage present?

Yes

- Repair the short to voltage in the (P39) PEM Liftgate Lock/Unlock Switch Return circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 11

11. (P30) PEM LIFTGATE LOCK/UNLOCK SWITCH SENSE CIRCUIT SHORTED TO VOLTAGE




1. Measure the voltage between ground and the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit in the License Plate Lamp Bar harness connector.

Is there any voltage present?

Yes

- Repair the short to voltage in the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the License Plate Lamp Bar Assembly. Exterior Handle Lamp Bar - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

12. PEM LIFTGATE LOCK/UNLOCK SWITCH SHORTED TO VOLTAGE




1. Turn the ignition off.
2. Re-connect the License Plate Lamp Bar harness connector.
3. Turn the ignition on.
4. While measuring the voltage in the following step, have a helper press and hold the PEM Liftgate Lock/Unlock Switch button.
5. Measure the voltage between ground and the (P30) PEM Liftgate Lock/Unlock Switch Sense circuit in the PEM C1 harness connector.
6. Measure the voltage between ground and the (P39) PEM Liftgate Lock/Unlock Switch Return circuit in the PEM C1 harness connector.

Is there any voltage present in either or both circuits while the switch is being pressed?

Yes

- Replace the License Plate Lamp Bar Assembly. Exterior Handle Lamp Bar - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the Passive Entry Module. Passive Entry Module - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.