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Fog Lamp Relay Circuit Shorted Lo/Open

When Monitored: With the ignition switch in the on position.

Set Condition: This DTC sets if no voltage is seen at the fog lamp relay control circuit cavity.

Possible Causes are:

  1. Check Junction Block fuse No. 24. Is fuse No. 24 open? If yes, go to next step. If no, go to step  4 .
  2. Remove the Fog Lamp Relay from the Junction Block. Using an ohmmeter measure the Fog lamp relay coil terminals No. 85 and 86. Is the resistance between 70 and 80 ohms? If yes, go to next step. If no, replace the fog lamp relay. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  3. Remove the Fog Lamp Relay from the Junction Block. Using an ohmmeter measure the Fog Lamp Relay Output circuit to ground. Is the resistance less than 0.5 ohm? If yes, repair the relay output circuit for a short to ground and replace the fuse if necessary. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS. If no, replace the fuse. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  4. Looking at the Junction Block, see if the Fog Lamp Relay is present. Is the relay present? If yes, go to next step. If no, install the missing relay. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  5. For the results of this test to be valid voltage must be present at the Junction Block C5 connector cavity No. 3. Measure the voltage of the B (+) circuit to fuse No. 24. Is the voltage more than 10 volts? If yes, go to next step. If no, replace the junction block. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  6. Remove the Fog Lamp Relay from the Junction Block. Measure Fused B+ cavities for the Fog Lamp Relay in the Junction Block. Is the voltage more than 10 volts at both cavities? If yes, go to next step. If no, replace the junction block. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS.
  7. Install a known-good relay in place of the Fog Lamp Relay. Does the system operate correctly? If yes, replace the fog lamp relay. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS. If no, go to next step.
  8. Remove the Fog Lamp Relay from the Junction Block. Turn ignition off. Remove the Body Control Module from the Junction Block. Measure the resistance of the Fog Lamp Relay Control circuit between the relay and the Body Control Module. 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.
  9. Remove the fog lamp relay from the Junction Block. Turn ignition off. Remove the Body Control Module from the Junction Block. Measure the resistance of the Fog Lamp Relay Control circuit to ground. Is the resistance less than 10 ohms? If yes, replace the junction block. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS. If no, go to next step.
  10. If there are no possible causes remaining, replace the Body Control Module. Perform BODY VERIFICATION TEST VER 1  under VERIFICATION TESTS.
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