First off, I love the site. Been lurking for awhile, and now I need your help.

The other day I noticed that my cruise control wasn't working. Then the other day, after trying to hook up a trailer, I noticed the brake lights don't work either.

Truck is a 2004 Tahoe and the only thing I did lately, was I added new lights to the footwells by tapping into an interior dome light circuit. Now, I've already checked all the brake fuses and they are all good. With a test light, I found that 'stop lp' underhood is hot all the time, "veh stop" and "vh cmsl" on the side of the dash, neither one lit up while pressing the brake pedal. So I was thinking maybe it was the brake light switch. However I found the break light switch and the orange line does have power and when i hit the brake pedal, the white wire becomes hot.

So maybe a ground came loose when I was fooling with those footwell lights?

Another guy had suggested possibly the flasher module, which i'm wondering about because the flashers both work fine, however with the trailer hooked up, the turn signals on the trailer didn't correspond to the signals on my truck.

Any help would be appreciated so that I can take my truck to myrtle beach in a week.

 

the lack of corodination between the turn signals on the truck and the trailer is a ground issue, this usually resolves itself with a little driving, but what I have done before is use some steel wool on the hitch ball and coupler. Check the ground wire from the harness and make sure it has a good ground. as far as the cruise goes there should be a fuse for it that should be hot with the key on (it was alot simpler in the early days when cruise worked on vacuum) the brake light switch could very well be the problem

 

I don't have a remedy for your cruise control issues, but your trailer issues I might be able to help. I had the same problem with the trailer wiring. Look to see if your fuses for the trailer wiring are not blown under the hood. Two of mine were blown. Check your grounds. That almost always is the culprit for lights not working properly.

 

i believe you guys are right with the trailer issues being a bad ground. the trailer wiring was a little suspect when i checked it out.

just wish i could tell for sure if the brake light switch was bad.

 

with the cruise control unhhok the battery and hook it back up, reset the computer in other words. . i have an 07 silverado and have to do it once a month for my cruise control.

 

but i have a feeling that the cruise control issue is related to the no brake light issue.

 

it is related to the no brake light issue...reason......the brake light switch turns off the cruise when you hit the pedal....change the switch

 

it just gets better.

just took it for a drive and the cruise control worked, but the brake lights still didn't work. so i am guessing that a ground somewhere is possibly loose? i guess i must have jarred something loose when i was trying to hook up those footwell lights.

 

well, after not doing anything really, everything works again. something must not have liked it when i hooked up those footwell lights.