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Dillmation's avatar
Dillmation
Explorer
May 19, 2013

Can't make any Adjustments on my trailer brakes

I have a 99 gmc sierra, new style, and recently replaced the 6-pin trailer connector to the 7-blade connector, my mechanic hooked this all up and now i dont have any adjustment for the brakes, the brakes are just on full power, they lock up, when the brakes are applied and will not turn down the adjustment to lessen the tension on the brakes, we hooked up another controller and the same thing happened, i hooked my camper up to another truck and the brakes on the camper work fine, so it must be something in the wiring or fuse.....any thoughts? thanks all!!

19 Replies

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  • donn0128's avatar
    donn0128
    Explorer II
    May 19, 2013
    Download the bargman wiring schematic from the internet and compare it to what your highly skilled mechanic did. If it does not match then yes he is an idiot. Guarantee he wired the brake light switch to the brake terminal on the receptacle.
  • Dillmation's avatar
    Dillmation
    Explorer
    May 19, 2013
    the other controller was a digital one and the numbers didnt show....the light were on but the adjustment numbers didnt show...
  • therink's avatar
    therink
    Explorer
    May 19, 2013
    Sounds like brake light hot wire is connected to the trlr brake pin on the connector. Do you have brake lights?
    An easy way to test it is used a voltage meters and check each pin as the brakes are applied. Should be brake light hot when brakes applied, aux hot(all the time) and trlr brake hot when brakes applied (voltage will vary depending on gain set at controller. 3 hot total. If running lights are on then 4 hot total.
    Steve
  • Dillmation's avatar
    Dillmation
    Explorer
    May 19, 2013
    also he isnt an idiot...everyone doesnt know everything....how do we fix this?
  • donn0128's avatar
    donn0128
    Explorer II
    May 19, 2013
    The idiot who did the wiring probably wired from the brake lights to the brake pin on the receptacle.
  • Dillmation's avatar
    Dillmation
    Explorer
    May 19, 2013
    yeap i do, then a harness that connects to underneath the dash...the brakes just lock up when applied...will not turn down, we even tried another box to make sure so its something in the wiring....
  • donn0128's avatar
    donn0128
    Explorer II
    May 19, 2013
    Sounds like your mchanic screwed up. I'll bet he has something wired wrong. Download the bargman brake wiring schemtic from the internet and check it out.
  • Vulcaneer's avatar
    Vulcaneer
    Explorer
    May 19, 2013
    Do you have a brake controller installed? Sounds like it is direct connect to the brake switch.

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