A Preliminary Information

IMPORTANT: The following steps must be completed before using the symptom tables.

1. Perform the A Diagnostic System Check - Lighting Systems before using the Symptom Tables in order to verify that ail of the following are true:
^ There are no DTCs set.
^ The control module(s) can communicate via the serial data link.
2. Review the system operation in order to familiarize yourself with the system functions. Refer to:
^ Headlights/Daytime Running Lights (DRL) Circuit Description
- Fog Lights Circuit Description
- Headlight Doors Circuit Description
- Exterior Lights Circuit Description
- Interior Lights Circuit Description
- Interior Lights Dimming Circuit Description

Visual/physical Inspection
^ Inspect for aftermarket devices which could affect the operation of the Lighting System. Refer to Checking Aftermarket Accessories in Diagrams.
^ Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

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

Symptom List
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:
- Backup Lamps Always On
- Backup Lamps Inoperative
- Component Illumination Lamps Inoperative (Door Switch)
- Component Illumination Lamps Inoperative (HVAC Control Assembly)
- Component Illumination Lamps Inoperative (PRNDL)
- Component Illumination Lamps Inoperative (TCS Switch)
- Courtesy Lamps Inoperative
- Daytime Running Lamps (DRL) Headlamps Inoperative (Day Light Conditions)
- Daytime Running Lamps (DRL) Headlamps Inoperative (Low Light Conditions)
- Fog Lamp Indicator Inoperative - Front (or Rear)
- Fog Lamps Always On
- Fog Lamps Always On - Rear
- Fog Lamps Inoperative - All
- Fog Lamps Inoperative - Rear
- Fog Lamp Switch Illumination Lamp Inoperative
- Hazard Lamps Inoperative
- Headlamps Inoperative - Low Beams
- Headlamps Inoperative - High Beams
- Headlamps Inoperative - One Lamp
- Headlamps Inoperative - Low and High Beams
- Headlamp Doors Inoperative - One Door
- Headlamp Doors Do Not Open
- Headlamp Doors Do Not Close
- IP Lamps Erratic with Dimmer Switch
- Park Lamps Inoperative - Rear
- Park, Tail and Side Marker Lamps Inoperative
- Stop Lamps Inoperative - All (Export)
- Stop Lamps Inoperative - CHMSL Operates (US and Canada)
- Stop Lamps Inoperative - Center High Mounted (US and Canada)
- Turn Signal Lamps Inoperative (All)
- Turn Signal Lamps Inoperative (Left Front)
- Turn Signal Lamps Inoperative (Right Front)
- Turn Signal Lamps Inoperative (Left Rear)
- Turn Signal Lamps Inoperative (Right Rear)