Diesel Place banner

1 - 9 of 9 Posts

·
Registered
Joined
·
24 Posts
Discussion Starter #1
help please i have no brakes light, changed the bulbs, both left and right tail light fuses were blown, checked stop light fuse its good. third brake light work and rear running lamps work, just no brake lights...PLEASE HELP i dont know what else to do???

thanks in advance,
kevin
 

·
Registered
Joined
·
358 Posts
Blown fuses, definitely a short to ground. Tail lights work after fuse replacement? If you've had any work done with the hitch wiring, check that area first - usually the prime culprit.
 

·
Registered
Joined
·
24 Posts
Discussion Starter #3
no never done anything with the trailer harness or wiring..barely use the hitch....i replaced the fuses for the running tail lamps, then they worked no problem....however the brake lights wont come on, the third brake light will come on so i know the switch is good....pulled the fuse for the stop lamps then no third brake light...put it back in and still no tail brake lights.

when i probed the wires at the tail lights they were getting power for the running tail lamps, but i couldnt probe a wire and find power to the socket when the brake pedal is pressed

what could be wrong with the trailer wiring that could cause this?

thanks
kevin
 

·
Registered
Joined
·
358 Posts
what could be wrong with the trailer wiring that could cause this?
Trailer wiring probably isn't the issue then. There may be a pig tail for a 5th wheel hook up at the front of the bed on the driver side that would have all lighting connections (if your truck came with that option). If you have 12v on the stop lamp wire when the brake pedal is applied, the problem will be towards the back of the truck. Either a connection has corroded on the connector block (left rear bumper area) or come loose. I'm still wondering what may have caused the fuse failure, there's a good chance that may be related.
 

·
Registered
Joined
·
65 Posts
There is three differant fuses for the stop lights one is labled stop lp and it's 25 amps and that kills all power to brake light circuits and there is a VEH STOP 15A fuse for just your taillights and a VEH CHMSL 10A fuse just for your center light
 

·
Registered
Joined
·
358 Posts
SpeedII, I'm glad you had time to research this for Denalidmax. Didn't have time myself. Hope this helps. . . sounds totally logical!
 

·
Registered
Joined
·
27 Posts
Could be the switch at the pedal?

Maybe GM is still using the same old multi-contact switch at the brake pedal. My previous Blazer was on its fourth in 9 years when I sold it. Seems like there was just too much current for the contacts (I never towed or had any accessories connected to that circuit) and they carboned-up. I got to be really good at changing them and they are cheap (literally and figuratively)!
 

·
Registered
Joined
·
65 Posts
Has one feed for brake lights if any brake light works it's not the switch
 

·
Registered
Joined
·
275 Posts
Trailer wiring is on a seperate system and has its own fuses but can backfeed some when the 7 way connector gets corroded. Had a truck in our shop one day doing the same thing and it was the body computer causing all the problems. GM swapped it out and fixed the thing in 45 minutes.
 
1 - 9 of 9 Posts
Top