Circuit Description
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
When the BCM senses that the front fog lamp switch signal circuit is grounded momentarily by pressing the front fog lamp switch, the BCM energizes the front fog lamp relay by grounding the front fog lamp relay control circuit. The front fog lamp indicator is also illuminated utilizing the same fog lamp relay control circuit.