LED Headlight issue. Please Help!!
Thread Starter
3rd Gear
Joined: Jun 2026
Posts: 3
Likes: 0
From: North GA
LED Headlight issue. Please Help!!
Hello all! This is my first post on the forum and i’m excited to get to meet new people. I am currently dealing with a very frustrating issue on my C5. I put LED headlights in, and they refuse to stay on for extended periods of time. Them going up or down seems to be largely unaffected, but the headlights themselves like to shut off on me at random. Thankfully I have bright fog lights, or else i’d be screwed. I can’t seem to find the problem, I’ve replaced the multi function switch, the battery is brand new, the alternator is putting out what it’s supposed to be, i’ve replaced fuses, I put in a new hazard switch, even put in resistors and still these headlights refuse to stay on. I have noticed my Voltage isn’t as high as i think it should be. Sitting in traffic it can get as low as 11.3, then driving the alternator will charge it back up to about 13. The bulbs are from Vette Lights, which is a very good company, as I have all of there other lighting (Taillights, Side Markers, etc) i’m just unsure of the issue and it leads me to not be able to drive at night, which isn’t ideal. Any help would be greatly appreciated, apologies for the long post, but I need help!!
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,633
Likes: 4,078
From: Cape Coral, Florida
If your charging voltage is dropping down to 11 volts you need to perform a voltage drop check of your charging system if you have a DMM and know how to use it...if not take your car to your local automotive electrical repair shop.
Pro
Joined: Jan 2001
Posts: 650
Likes: 349
From: San Jose CA
Agreed - start off with an alternator and battery test. Both can be done for free at most auto parts stores. Find out with the low voltage is the cause or a symptom
Quick question - do your high beams work?
Quick question - do your high beams work?
Thread Starter
3rd Gear
Joined: Jun 2026
Posts: 3
Likes: 0
From: North GA
I appreciate the input sir! Yes I do, I will have to look into that!
Thread Starter
3rd Gear
Joined: Jun 2026
Posts: 3
Likes: 0
From: North GA
High Beams work when the low beams do, however when they have their moment of shutting off the high beams go with them. Sometimes when the low beams go off, I can turn the high beams on as well and they’ll work for maybe all of 5 seconds before they shut off too. The most confusing part is these headlights worked fine for a few months until they started acting up.
