No Brake and Turn Signals On Boat Trailer with 5-Way to 7-Way Adapter

Question:

I bought a new boat with a trailer.It has five flat my truck has four flat but I also have a round 7 blade. Bought a adapter number 47385 Hopkins .Still cannot get the signal lights or brake lights to work.The truck is a 2014 Platinum. The adapter should work am I correct.

asked by: Andy

Expert Reply:

For starters, have you tested the pins inside the 7-way trailer connector on the vehicle to make sure these circuits are active? If not I would do just that but the Adapter 7-Pole to 4-Pole and 5-Pole part # 37385 will only work for you if both the vehicle and trailer are wired the exact same way. I have attached the standard(ish) trailer wiring diagram for you. If I had to guess, I would say that the vehicle side is correct but the trailer side does not match this. Therefore, I recommend you check the way that you trailer side connector is wired.

There could also be an issue inside the adapter and I almost never recommend using them so now might be a good time to remove the 5-way and install a 7-way with part # PK12706. All you need to do for this is cut off the old connector and replace it with the above making sure to put the wires in the correct position. If this does not work then you most likely have an issue with the trailer wiring. If you need redo this you can use the Trailer Wiring 7-Way Upgrade Kit part # HS381-9000.

expert reply by: Conner L