Forum Discussion

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 bra...
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

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