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Third Brake light not working

NYMetsFan86

By NYMetsFan86
in Ask A GM Technician

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NYMetsFan86 Enthusiast

NYMetsFan86

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I was outside my truck while it was running last night ans noticed the third brake light was off. I had someone stand behind it while I hit the brakes, no light. I then had someone stand off to the side while I put it in reverse. Still no light. Should I test the harness? Any ideas? I am now uncertain how long it has been out or how to troubleshoot and find out what the issue is. Thanks

 

2017 silverado LT Crew 4x4

newdude Senior Enthusiast

newdude

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Warranty. Getting somewhat common on these K2 trucks. All we've seen are blown bulbs and one or two cracked housings like the GMT-900 CHMSL used to do from being over tightened at the factory.

JimCost2014 Senior Enthusiast

JimCost2014

Posted
Posted

I was outside my truck while it was running last night ans noticed the third brake light was off. I had someone stand behind it while I hit the brakes, no light. I then had someone stand off to the side while I put it in reverse. Still no light. Should I test the harness? Any ideas? I am now uncertain how long it has been out or how to troubleshoot and find out what the issue is. Thanks

 

2017 silverado LT Crew 4x4

Check the fuse in the large fuse box in the engine compartment. Had the fuse for the 3rd brake light fail in my 08, had to replace the whole box because you can not fix just one fuse port.

NYMetsFan86 Enthusiast

NYMetsFan86

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Check the fuse in the large fuse box in the engine compartment. Had the fuse for the 3rd brake light fail in my 08, had to replace the whole box because you can not fix just one fuse port.

 

gonna give this a try and see what happens. Will report back, Im guessing if the fuse box went its a warranty replacement but i never want to assume

JimCost2014 Senior Enthusiast

JimCost2014

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gonna give this a try and see what happens. Will report back, Im guessing if the fuse box went its a warranty replacement but i never want to assume

If that is the problem, could not see why it would not be warranted. When the 08 went bad, it actually blew both bulbs, so I replace the 3rd brake light thinking that was it, but when I plugged it in, no power. The dealer was actually the one who found out it was the fuse box not sending power to the light.

NYMetsFan86 Enthusiast

NYMetsFan86

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fuse does not look blown, need to grab a multi tester after work to check the harness. ..I was hoping it was the fuse.

  • 4 years later...

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