Tailgate Lock Inoperative

Possible Causes:

• DTC's Present
• Tailgate Lock Driver Open
• Tailgate Lock Motor Open
• Tailgate Lock Driver Short To Ground
• Tailgate Unlock Driver Open
• Tailgate Unlock Driver Short To Ground
• Junction Block Open
• Body Control Module-Tailgate Driver Open

Testing

1. With the DRBIII(R), read DTC's. Are there any Tailgate related codes present? If yes, see POWER DOOR LOCKS/RKE  for related problems. Perform BODY VERIFICATION TEST  . If no, go to next step.
2. Disconnect the Tailgate Lock Motor connector. Connect a test light between the Tailgate Lock Driver circuit and the Tailgate Unlock Driver circuit in the Lock Motor connector. With the DRBIII(R), actuate the UNLOCK TAILGATE. With the DRBIII(R), actuate the LOCK TAILGATE. Did the test light illuminate when the motor was actuated in both directions? If yes, replace the Tailgate Lock Motor. Perform BODY VERIFICATION TEST  . If no, go to next step.
3. Connect a jumper wire between Tailgate Lock Driver circuit and ground in the Lock Motor connector. Disconnect the Junction Block C2 connector. Measure the resistance between ground and the Tailgate Lock Driver circuit in the Junction Block C2 connector. Is the resistance below 5.0 ohms? If yes, go to next step. If no, repair the Tailgate Lock Driver circuit for an open. Perform BODY VERIFICATION TEST  .
4. Measure the resistance between ground and the Tailgate Lock Driver circuit in the Junction Block C2 connector. Is the resistance below 1000.0 ohms? If yes, repair the Tailgate Lock Driver circuit for a short to ground. Perform BODY VERIFICATION TEST  . If no, go to next step.
5. Connect a jumper wire between Tailgate Unlock Driver circuit and ground in the Lock Motor connector. Measure the resistance between ground and the Tailgate Unlock Driver circuit in the Junction Block C2 connector. Is the resistance below 5.0 ohms? If yes, go to next step. If no, repair the Tailgate Unlock Driver circuit for an open. Perform BODY VERIFICATION TEST  .
6. Measure the resistance between ground and the Tailgate Unlock Driver circuit in the Junction Block C2 connector. Is the resistance below 1000.0 ohms? If yes, repair the Tailgate Unlock Driver circuit for a short to ground. Perform BODY VERIFICATION TEST  . If no, go to next step.
7. Remove the Junction Block. Remove the Body Control Module from the Junction Block. Measure the resistance of the Tailgate Lock Driver circuit between Junction Block C2 connector and the Junction Block - BCM connector. Measure the resistance of the Tailgate Unlock Driver circuit between Junction Block C2 connector and the Junction Block - BCM connector. Is the resistance below 1.0 ohm on both circuits? If yes, go to next step. If no, replace the Junction Block. Perform BODY VERIFICATION TEST  .
8. If there are no possible causes remaining, replace the Body Control Module. Perform BODY VERIFICATION TEST  .