GM Service Manual Online
For 1990-2009 cars only

Important: Review the Exterior Lighting Systems Description and Operation and the Interior Lighting Systems Description and Operation in order to familiarize yourself with the system functions.

Visual/Physical Inspection

    • Inspect for aftermarket devices which could affect the operation of the system. Refer to Checking Aftermarket Accessories in Wiring Systems.
    • Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
    • Inspect all related ground points for being clean and tight.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

    •  Automatic Lamp Control Inoperative
    •  Low Beams Inoperative
    •  High Beams Inoperative
    •  Backup Lamps Always On
    •  Backup Lamps Inoperative
    •  Console Lamp Always On
    •  Console Lamp Inoperative
    •  Daytime Running Lamps (DRL) Always On
    •  Daytime Running Lamps (DRL) Inoperative
    •  Dome Lamps Always On
    •  Dome Lamps Inoperative
    •  Fog Lamps Always On
    •  Fog Lamps Inoperative
    •  Hazard Lamps Always On
    •  Hazard Lamps Inoperative
    •  High Beam Indicator Always On
    •  High Beam Indicator Inoperative
    •  Park Lamps Always On
    •  Park Lamps Inoperative
    •  Stop Lamps Always On
    •  Stop Lamps Inoperative