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Third Brake Light

Toxicgoober

By Toxicgoober
in Troubleshooting & Recalls

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Toxicgoober Enthusiast

Toxicgoober

Posted
Posted

Someone who was following me the other night told me my third brake light wasn't coming on. This is the one on the roof of the cab along with the bed light. My bed light turns on fine, but sure enough the brake light did not illuminate when brake pedal was depressed or when the headlights were activated. Then today I noticed 2 other newer Sierras with the same thing. Is this just how the trucks are? I thought legally you had to have a third brake light.

 

 

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x219c Enthusiast

x219c

Posted
Posted

Someone who was following me the other night told me my third brake light wasn't coming on. This is the one on the roof of the cab along with the bed light. My bed light turns on fine, but sure enough the brake light did not illuminate when brake pedal was depressed or when the headlights were activated. Then today I noticed 2 other newer Sierras with the same thing. Is this just how the trucks are? I thought legally you had to have a third brake light.

 

 

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Sounds like a burnt out bulb. Guessing it's common if you saw a couple others like that.

 

 

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Toxicgoober Enthusiast

Toxicgoober

Posted
  • Author
Posted

Did you check the bulb?

Didn't try replacing it yet. Since I've seen so many people around without that light illuminated I wanted to see if y'all new something I didn't. I'll replace it tomorrow. I wonder why these trucks seem to go through the bulbs so fast?

 

 

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O_J_Simpson Senior Enthusiast

O_J_Simpson

Posted
Posted

Didn't try replacing it yet. Since I've seen so many people around without that light illuminated I wanted to see if y'all new something I didn't. I'll replace it tomorrow. I wonder why these trucks seem to go through the bulbs so fast?

 

 

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They are typical light bulbs and they burn out. Nothing special. Legal depends on your country and state.

JimCost2014 Senior Enthusiast

JimCost2014

Posted
Posted

not sure if this your problem, but on my 2008 the under hood fuse box, the large one, had one fuse slot stop working, the 3rd brake light. even thought every other fuse worked fine, they had to replace the whole box. $550.00 plus for the new unit and installation.

Colossus Senior Enthusiast

Colossus

Posted
Posted

I see a lot of euro and Asian cars that have brake lights burned out or not working on vehicles less than 5 years old. It seems to becoming more common now with Ford GM and Chrysler. Hopefully the bulb is burned out. If not, then you will need to start looking at the brake light switches. FYI 1 switch somewhere around the brake pedal will control 2 out of 3 lights, and the other light is controlled by another switch, for redundancy purposes.

Amuro Enthusiast

Amuro

Posted
Posted

I'm new to the forum/ website and recently just bought my new 2016 Chevy Silverado 1500 AND a prior GMC Tech. Your third brake light should turn on period, check the bulb and or fuse. Texas law, you don't need a third brake light, so in Texas if your third brake light is not working then you are still good. I recently installed Sylvania LED 921 on the cargo lights which is 2 of them and 1 for the third brake light. Mines does turn on when I brake so if your truck is under factory warranty then take it in to get checked. Hope this helps.

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