Headlights not working correctly?

2004 CHEVROLET SILVERADO

193,000 MILES • 5.3L • V8 • 2WD • AUTOMATIC

JOSUE RODRIGUEZ2

MEMBER
23 POSTS
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Hello, my headlights seem to not be working correctly, and I think it might be the switch. I just purchased this car a week ago and need to fix it ASAP. I think the switch might not be making a good connection. A wiring diagram of the front headlight system would be greatly appreciated! Thank you.

Apr 28, 2025 at 6:23 PM

STRAILER

✓ASE Certified Mechanic
54,503 POSTS

There are 6 fuses, four relays and the BCM that controls the headlamps, I would check these first, here is a guide to help you test the fuses and I have included the headlight wiring diagrams to show you which fuses and relays to check.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Check out the images (below). Let us know how it goes, please get back to us!

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Professional Diagram for 2CarPros Members
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Apr 29, 2025 at 12:01 PM

JOSUE RODRIGUEZ2

MEMBER
23 POSTS

Thanks. Just so i can get a better visual, is there one on the parking lamps/side markers as well?

Apr 29, 2025 at 12:52 PM

STRAILER

✓ASE Certified Mechanic
54,503 POSTS

Sure, here is the running light wiring diagrams as well. Let me know how it goes.

Images (Click to enlarge)

Professional Diagram for 2CarPros Members
Click here to log in and view diagram.

Apr 30, 2025 at 10:19 AM