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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 bra...
Bonefish's avatar
Bonefish
Explorer
May 20, 2013
I just went to a trailer rental shop (U-Haul in my case had one) and purchased a pre-wired 7-connector socket with adaptor. The adaptor plugged into the existing wiring harness on my truck.

One thing I forgot to mention I have seen a few wiring diagrams on the net that were just plane wrong/colors swithched/plug key drawn in the wrong place/etc.

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