GM Service Manual Online
For 1990-2009 cars only

Important: The following steps must be completed before using the symptoms tables.

Review the system operation in order to familiarize yourself with the system functions. Refer to the following procedures:

    •  Exterior Lighting Systems Description and Operation
    •  Interior Lighting Systems Description and Operation

Visual/Physical Inspection

Several of the symptom procedures ask for a careful visual/physical inspection. This step is extremely important. It could lead to correcting a problem without further checks and can save valuable time.

These checks include the following:

    • Inspect for aftermarket devices which could affect the operation of the lighting system. Refer to Checking Aftermarket Accessories in Wiring Systems.
    • Inspect the easily accessible or visible system components and harness connectors for obvious damage or conditions which could cause the symptom.
    • If only one lamp is inoperative, inspect and repair a poor connection or an open in the power feed or ground circuit before replacing the light bulb. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

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 Transaxle Gear Position Illumination Lamp Inoperative, All Other Instrument Lamps OK
    •  Headlamps-On Reminder Chime Inoperative
    •  Low Beams Inoperative
    •  High Beams Inoperative
    •  Low and High Beams Inoperative
    •  Parking Lamps and Taillamps Inoperative
    •  High Mount Stop Lamp Inoperative
    •  Rear Cargo Area Lamp Inoperative
    •  Front Fog Lamps Inoperative
    •  Backup Lamps Inoperative
    •  Daytime Running Lamps (DRL) Inoperative
    •  Dome Lamps Inoperative
    •  Hazard Lamps Inoperative
    •  Instrument Panel Illumination Lamps Inoperative
    •  Instrument Cluster Indicator Lamps
    •  Stop Lamps Always On
    •  Stop Lamps Inoperative
    •  Turn Signal Lamps and/or Indicators Inoperative