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Rear Fog Lamp Relay Circuit Open

When Monitored: Ignition switch in the On position and the IOD fuse installed.

Set Condition: This DTC sets if the BCM does not detect any voltage on the control circuit.

Possible Causes are:

  1. Remove the Rear Fog Lamp Relay from the Junction Block. Using a 12-volt test light connected to ground, probe cavity No. 85 of the Rear Fog Lamp Relay connector. Is the test light illuminated? If yes, go to next step. If no, go to step  6 .
  2. Remove the Rear Fog Lamp Relay from the Junction Block. Turn ignition on. Using a 12-volt test light connected to 12 volts, probe cavity No. 86 of the Rear Fog Lamp Relay connector. Using the DRBIII(R), enter Body, Body Computer, then Actuator Tests. While monitoring the test light, actuate the Rear Fog Lamp Relay. Does the test light flash on and off as the relay is actuated? If yes, replace the rear fog lamp relay. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS. If no, go to next step.
  3. Turn ignition off. Remove the Rear Fog Lamp Relay from the Junction Block. Remove the BCM from the Junction Block. Measure the resistance between ground and cavity No. 86 of the Rear Fog Lamp Relay connector. Is the resistance less than 5 ohms? If yes, replace the junction block. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS. If no, go to next step.
  4. Turn ignition off. Remove the Rear Fog Lamp Relay from the Junction Block. Remove the BCM from the Junction Block. Measure the resistance of the Rear Fog Lamp Relay Control circuit between the Rear Fog Lamp Relay connector cavity No. 86 and the Junction Block BCM connector cavity No. 13. Is the resistance less than 5 ohms? If yes, go to next step. If no, replace the junction block. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  5. If there are no possible causes remaining, replace the Body Control Module. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  6. Inspect fuse No. 27 in the Junction Block. Is the fuse open? If yes, go to next step. If no, Check the B+ feed circuit from the PDC fuse for an open or short. If okay, replace the Junction Block. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  7. Remove the Rear Fog Lamp Relay from the Junction Block. Turn ignition off. Measure the resistance between ground and cavity No. 30 of the Rear Fog Lamp Relay connector. Is the resistance less than 5 ohms? If yes, replace the Junction Block. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS. If no, go to next step.
  8. Turn ignition off. Remove the Rear Fog Lamp Relay from the Junction Block. Remove the BCM from the Junction Block. Measure the resistance between ground and cavity No. 86 of the Rear Fog Lamp Relay connector. Is the resistance less than 5 ohms? If yes, replace the Junction Block. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS. If no, go to next step.
  9. Turn ignition off. Remove the Rear Fog Lamp Relay from the Junction Block. Replace Fuse No. 27 in the Junction Block with a good fuse. Connect a jumper wire between cavity No. 30 and cavity No. 87 of the Rear Fog Lamp Relay connector. Inspect fuse No. 27 in the Junction Block. Is the fuse open? If yes, check the Rear Fog Lamp Relay Output circuit for a short to ground. If okay, replace the Junction Block. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS. If no, replace the rear fog lamp relay. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS.
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