LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2006 >> Sierra 1500 HD, RWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1293 (Lighting Systems) >> Diagnostic Information and Procedures >> Front Fog Lamps Malfunction >> Circuit/System Testing >> Fog Lamp Switch Malfunction

Fog Lamp Switch Malfunction

WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the harness connector at the headlamp switch.
  2. Verify that a test lamp illuminates between B+ and the ground circuit terminal 8.
    • If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool Front Fog Lamp Switch parameter is Inactive.
    • If not the specified value, test the signal circuit terminal 10 for a short to ground. If the circuit tests normal, replace the BCM.
  4. Install a 3A fused jumper wire between the signal circuit terminal 10 and the ground circuit terminal 8. Verify the scan tool Front Fog Lamp Switch parameter is Active.
    • If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
  5. If all circuits test normal, test or replace the headlamp switch.