Brake Lights & Cruise Control Not Working

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MeanGreen03

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So as I took a trip down to Fort Worth to get the Tahoe tuned by Justin the cruise control worked fine. When Justin tuned it and told me to turn on cruise control it wouldn't work. We were both dumbfounded and didn't know what was going on. Well last night I asked a friend if my brake lights were working and as I found that they weren't (not even the 3rd brake light). I checked the fuses and they were good. What might be the culprit??
 

vatahoelt

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possibly the brake control module(meant to say brake light switch). little white plastic box located up on the brake pedal assembly.

also, it could be another fuse not related to the brake light circuits.
 
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05Yukon

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Look under your truck above the factory tail pipe location there is a box there with 6 plugs in it I believe. All of the brake light wiring runs into that check those connections make sure they are tight and there is no mud in them.
 

05Yukon

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I had the same problem when i installed my led tails check the fuse panel inside the door

LEDs cause this problem because they dont pull much power so the computer thinks there is a bulb out so it wont let the cruise engage. But your brake lights still work. With LEDs its just a resistance problem. I would check that box with all the connectors above your tail pipe to make sure I have seen it cause some weird issues including the brake lights and cruise. Do your turn signals work normal?
 

Krunchy

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I put one of the connections in upside down and it blew a few fuses and my brake lights and cruise didnt work but the center brake light above the hatch did work i found the offending fuse and the problem was fixed
 
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MeanGreen03

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I have stock tails. Like I said it all of a sudden did this without anything being changed. Oddly enough everything started working again (for now). I'm still going to check the connections as mentioned. The turn signals and reverse lights worked normal. I absolutely hate electrical problems!
 

vatahoelt

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I have stock tails. Like I said it all of a sudden did this without anything being changed. Oddly enough everything started working again (for now). I'm still going to check the connections as mentioned. The turn signals and reverse lights worked normal. I absolutely hate electrical problems!

had you done any work underneath the dash lately? i had been working underneath mine and then I noticed my cruise didn't work and then my brake lights stopped working.

i had tried everything, that junction in the back under the rear bumper, a new brake light control module, all the fuses, everything.

i eventually just checked all plugs and made sure they were all connected and then everything worked again.

i did learn a lot though about the whole brake light circuit though.
 

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