Fog Lamps Always On
WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Fog Lamps Always On
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Fog Lights Schematics Connector End View Reference: Lighting Systems Connector End Views or Body Control System Connector End Views in Body Control System. |
|||
| 1 | Did you perform the Lighting Systems Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Verify that the front fog lamps are always on. Do the front fog lamps operate normally? |
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
| 3 | Remove the front fog lamp relay. Do the front fog lamps turn OFF? |
Go to Step 4 | Go to Step 7 |
| 4 |
|
Go to Step 5 | Go to Step 9 |
| 5 | Test the front fog lamp relay control circuit for a short to ground. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 10 | Go to Step 6 |
| 6 | Inspect for poor connections at the harness connector of the Body Control Module (BCM). Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 10 | Go to Step 8 |
| 7 | Repair the short to voltage in the front fog lamp supply voltage circuit. Refer to Wiring Repairs
in Wiring Systems. Did you complete the repair? |
Go to Step 10 | - |
| 8 |
IMPORTANT:
Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to Body Control Module Replacement
in Body Control System.Did you complete the replacement? |
Go to Step 10 | - |
| 9 | Replace the front fog lamp relay. Refer to Relay Replacement (Within an Electrical Center)
or Relay Replacement (Attached to Wire Harness)
in Wiring Systems. Did you complete the repair? |
Go to Step 10 | - |
| 10 | Operate the system in order to verify the repair. Did you correct the condition? |
System OK | Go to Step 3 |