Hi I have a 02 ford 350 class C RV. The RV comes with a 6way harness, and has no brake controller. The 26 trailer Im pulling has a 7way harness. Im going to but a brake controller on. How do I find the brake control wire in the truck that goes to the trailer harness on the back of the RV. If I there is a wire going from the dashboard to the trailer harness, that would controll the trailer brakes. Will part #47435 work. Is there anything else I need. Thank you
asked by: Brandon G
You will be able to use the 6 To 7-Way Adapter, part # 47435, to match the RV and trailer plugs, and you will also need to run a Blue brake controller output wire from the brake controller to the rear trailer connector. However there is another way to connect your trailer wiring that would eliminate the need for the # 47435 adapter.
What you can do, is check to see if there is a 4-way connector connected to your 6-way. If there is not a 4-way connected to the 6-Way, you can just cut the 6-way connector off and connect the wires to the Pollak 7-Way Connector and then run Blue Primary Wire, part # 10-1-1 to the brake controller. If there is a 4-Way plug into the back of the 6-way, you would need Adapter 4 Pole to 7 Pole, part # 30717. In each case, you will need to run Blue Primary Wire, part # 10-1-1, from the 7-way to the Blue wire on the brake controller. You will also need to run Primary Wire, part # 12-1-1, from the 7-way to the positive battery terminal via a 40 amp circuit breaker, part # 9510, if this wire is not already ran.
Part # 10-1-1, and part # 12-1-1 are sold by the foot, I would recommend ordering more than enough wire so that you are not short.
For a brake controller, I would recommend the Tekonsha Prodigy P2 Proportional Brake Controller, part # 90885. You will need to hard-wire the brake controller. The Black wire is 12 Volt power and will connect to the positive battery terminal via a 40 amp circuit breaker, part # 3808. The White wire is the ground and will connect to the negative battery terminal. The Blue wire is the brake control output and will connect to the Blue wire on the 7-way connector. The Red wire will connect to the stop light switch wire located near the brake pedal. You will need to use a circuit tester, part # 3808 to test and connect to the wire that only has signal when the brake pedal is pressed.
After installing the brake controller and wiring, you will need to test to make sure the trailer 7-Way matches the vehicle 7-way for function (see picture).
I have linked an FAQ on brake controller wiring and an FAQ on installing a brake controller from scratch that you may find as a good reference. I have also linked a picture showing the each pin function for vehicle and trailer 7-way connector.