A Symptoms - Lighting Systems

IMPORTANT: Complete the following steps before using the symptom tables.

1. Perform Diagnostic System Check - Lighting and Horns before using the Symptom Tables in order to verify that all of the following are true:
^ No DTCs are set. Diagnostic System Check - Lighting Systems
^ The control module can communicate via the serial data link.
2. Review the system operation in order to familiarize yourself with the system functions. Refer to Exterior Lighting Systems Description and Operation and Interior Lighting Systems Description and Operation.

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
^ Courtesy Lamps Inoperative
^ Courtesy Lamps Always On
^ Fog Lamps Always On
^ Fog Lamps Inoperative (Front)
^ Hazard Lamps Inoperative
^ Hazard Lamps Always On
^ Headlamps Always On - Low or High Beam
^ Headlamps Inoperative - Low Beams
^ Headlamps Inoperative - High Beams
^ Headlamps Inoperative - Low and High Beams
^ High Beam Indicator Inoperative
^ Interior Backlighting Inoperative
^ Illuminated Entry Lamps Inoperative
^ Park Lamp Out Indicator Inoperative
^ Park Lamps Always On
^ Park Lamps Inoperative
^ Park Lamps Inoperative - Output at Trailer/Upfitter Connector
^ Reading Lamp(s) Inoperative
^ Stop Lamps Always On
^ Stop Lamps Inoperative
^ Turn Signal Lamps and/or Indicators Inoperative
^ Turn Signal Lamps Inoperative - Output at Trailer/Upfitter Connector
^ Interior Lamps Off Switch Inoperative