What Circuit Does Boat Trailer with Surge Brakes Need Active so that it Can Reverse

Question:

I have been having trouble with the 7-Pin Connector on my Four Winns boat trailer, so I decided to plug into my 2008 Ford Explorers already installed 4 pin plug. Everything works, but now I see that the boat trailers has a blue wire that I am pretty sure that I need to attached for the trailer brakes. Can I just plug the 7-pin Connector in with only the blue wire attached leaving the remaining 4 pin plug unplugged? I would use the alternative 4 pin plug on my Explorer and just go ahead and plug in the 7-pin connector. Thanks. P.S. It is a Kodiak brake system for my 18 foot Four Winns speedboat.

asked by: Gary S

Expert Reply:

You actually need the reverse light circuit active on your trailer wiring so that your surge brakes can be temporarily deactived when backing up.

So what you'd need is a 4-way to 7-way adapter # 37185 and you'd need to connect the purple wire to the reverse light circuit on your tow vehicle.

expert reply by: Jameson C