Converting 4-Pole Trailer Connector to 7-Way


Converting 4-pole to 7-way

Expert Reply:

If the vehicle has an existing 4-pole trailer connector, and you are wanting to convert it to a 7-way, using an adapter like part # 37185 is your best bet. The adapter would plug directly into the existing 4-pole, with 4 wires remaining.

The blue wire would connect to the brake output wire from a brake controller. The black wire would connect to the vehicle battery via a 40 amp breaker like part # 9510, and would be used to maintain a trailer mounted battery, if needed. The white wire would ground to the trailer frame, and the purple wire would usually be used to power the trailer reverse lights, if needed.

Of all these connections, only the ground wire and the 4-pole is absolutely necessary.

If you would care to give me some more information regarding what you are trying to accomplish, I would be happy to provide some more specific information for you. The year, make and model of the tow vehicle and a brief description of the trailer would also be helpful.

expert reply by:
Michael L

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