On my Gulfstream, the blue brake wire was missing when I added the 7 pin connector to the existing 4 pin. I decided to use a #12 grounded orange extension cord and cut off the ends to run 3 wires front to back. I used one wire for the blue brake wire, and another for the 12 volt feed to the trailer or extra lights for the Toad. Used the third wire for a heavy ground which is really extra since the 4 pin connector already had a lighter-duty white ground wire.
Purchased the appropriate chassis to controller wiring adapter for under the dash, but never did find a mating connector. I concluded Gulfstream deleted that connector or used it for something else, so I cut and spliced as necessary.
My new 2019 Ram truck came with factory tow package, and the 7 pin connector is a flat blade connector rather than the round 7 holes. Another adapter purchase was required to be able to tow trailer with flat blade or round hole connector. Is this common? I thought the RV world used flat blade and semi trucks used round pin?
Originally Posted by Sudsy
On my 2005 Sun Voyager I want to add an electric brake system. I have the controller and understand the wiring. My coach is in storage right now but I was wondering if anyone here has done this job. Right now I have basic trailer wiring. A four pin rubber connector. I want to install the seven pin round receptacle on the coach. Will I find a connector in the rear of the coach underneath that provides for the seven pin install. Next part... Is there a connector under the dash that is for the brake controller. (or am I going to need a new wire ran from front to back)