Headlamps Inoperative - Low and High Beams
WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Headlamps Inoperative - Low and High Beams
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics Connector End View Reference: Lighting Systems Connector End Views or Body Control System Connector End Views in Body Control System. |
|||
| 1 | Did you perform the Lighting System Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 |
|
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
| 3 | Are both high and low beam headlamps inoperative? | Go to Step 4 | Refer to Headlamps Inoperative - Low Beams or Headlamps Inoperative - High Beams |
| 4 | With a scan tool, observe the headlamp switch parameter. Does the scan tool indicate ACTIVE? |
Go to Step 7 | Go to Step 5 |
| 5 | Connect a test lamp between the ground circuit of the headlamp switch connector and battery positive voltage. Does the test lamp illuminate? |
Go to Step 6 | Go to Step 9 |
| 6 | Test the headlamps switch headlamps on signal circuit of the headlamp switch for a high resistance, an open, or a short to voltage. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 12 | Go to Step 8 |
| 7 | Inspect for poor connections to the BCM. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 12 | Go to Step 10 |
| 8 | Inspect for poor connections to the headlamp switch. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 12 | Go to Step 11 |
| 9 | Repair the ground circuit of the headlamp switch. Did you complete the repair? |
Go to Step 12 | - |
| 10 |
IMPORTANT:
Perform the setup procedure for the body control module. Replace the body control module. Refer to Body Control Module ReplacementDid you complete the replacement? |
Go to Step 12 | - |
| 11 | Replace the headlamp switch. Refer to Headlamp Switch Replacement Did you complete the replacement? |
Go to Step 12 | - |
| 12 | Operate the system in order to verify the repair. Did you correct the condition? |
System OK | Go to Step 3 |