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myredracer's avatar
myredracer
Explorer II
Jun 26, 2019

TT brakes not working right - new truck & new wiring

Just rewired all the brake wiring in our TT to all #12 right up to the junction box in the A-frame. Recently installed the Prodigy P3 brake controller out of our old F250 in our "new" 2012 GMC Sierra...
enblethen's avatar
enblethen
Nomad
Jun 27, 2019
Refresh my old brain cells!
My memory tells me that the brake light lead only supplies control power to the controller. There is a separate power feed to controller that actually supplies power to the trailer brakes.

wiring diagram

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