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Posted

Has anyone figured out how to fix this issue with headlights not working at all on a 2015 Sierra? My fuse is fine. Both bulbs are fairly new, and are fine. Is there not a relay somewhere? The switch on the instrument panel works fine, the indicators on the dash tell me my lights are on, but they aren't .  Tail lights and parking lights all fine and fog lights fine. Hopefully someone can tell me this isn't going to be a $500 fix. 

Posted
On 6/29/2019 at 7:30 AM, Brockgibby said:

I have had the exact same problem as Nate. Did this get resolved? 

 
2014 GMC Sierra 1500, Last night I got into my truck and neither my high beams or low beams would turn on in my truck. The fog lights, turn signal/marker lights, and tail lights all work. I tried auto and on on the switch. I tested for power at the headlight fuse and did not have any with the headlights turned on. The light on the dash turns on indicating that the headlights are turned on.

I am having the same trouble no power to the head light fuse all other lights work what is the problem 

  • 1 month later...
Posted

there is no fuse on the low beams, the power comes straight from the bcm. both headlights come from x4 connector of the bcm. take a test light and check to see if there is power on pins 1 or 2. you cannot use a voltmeter because it will not offer enough resistance to trigger the output. here is the wiring diagram

gmc headlight.pdf

  • 4 months later...
Posted

I have a 2015 sierra 1500 and my Hi and low headlamps just stopped working. I got off work at 5am started my vehicle and realized that my lights won't come on no matter what I try. I live 45 minutes away from my job and now I can't drive without using my fog lamps and this is still dangerous as hell. Any suggestions on what's wrong? 

Posted
On 2/17/2020 at 7:04 AM, chuckworkb said:

Has anyone figured out how to fix this issue with headlights not working at all on a 2015 Sierra? My fuse is fine. Both bulbs are fairly new, and are fine. Is there not a relay somewhere? The switch on the instrument panel works fine, the indicators on the dash tell me my lights are on, but they aren't .  Tail lights and parking lights all fine and fog lights fine. Hopefully someone can tell me this isn't going to be a $500 fix. 

I just had the same thing happen to me this morning. Have you found out anything on the cause and how to fix it?

  • 1 month later...
Posted
On 10/9/2020 at 9:58 AM, gmckenzie said:

Add me to the list with this issue, and not finding an answer....

Well, I've got mine working. Not sure how helpful my solution is, but it did give me an idea of what is wrong.

My low beams had nothing but my high beams worked.

A couple years ago, I swapped out my headlights for some that were marginally better. Thinking my next step would be going back to the dealership, I went through the PITA of putting the originals back in so that the dealership wouldn't blame the headlights.

Well, the originals work fine (or as good as they can).

 

What I'm thinking is one of my low beam bulbs died, and it confused the BCM so neither worked. I tried resetting the computers by pulling the negative off the battery and taking a half hour before putting it back on, but that didn't do anything.

 

Anyway, sticking with the OEM and griping about the headlights again. But if I were to start over, I'd try a bulb or two first.

  • 2 months later...
Posted

I have the same problem. Suddenly last night both my headlights stopped working. Just the fog and the LEDs. Searched many forums and haven't found an answer, just a bunch of people with the same issue and zero response from GM. 

  • 2 weeks later...
Posted

I been working on the same issue that everyone report here and all has come to a BCM internal issue, if the issue continues happening  it should be report to the FCC as headlights are among the "security concern" on any vehicle, so GMC can recall and upgrade or replace the BC< at no cost. I already submitted the report 

  • 3 months later...
Posted

It’s a BCM ISSUE. I had to have mine replaced after both Hi and Low Beam went out in 2020. It happened after I had the TSB performed back in 2015. The dealer said the BCM circuit over heated. I’m guessing from the TSB to up the voltage for the TSB. 

  • 2 months later...
Posted

I'm a little tired of the posts that ask for a private email and vin #. Both headlamps going out at once is an emergency situation. Perhaps this should be a recall issue with so many complaints about the same problem with no resolutions.

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