Connecting 5 Wires From a Trailer to a 7-Way Trailer Connector

Updated 02/23/2012 | Published 02/22/2012

Products Featured in This Question

7-Way Round RV Style Trailer Connector - Trailer Side

(392)

$13.89

Hook Probe Circuit Tester

(66)

$14.36

Question:

My company has a trailer that has five wires coming out of it. Someone cut the plug off, and Ive been assigned to wire on a new one. The wire colors are: brown, black, white, green and yellow. The vehicle that pulled the trailer has a round, 7-pole plug. How can I wire 5 wires to a 7-wire plug? Help, please!

asked by: Seth W

Expert Reply:

The best solution for your situation would be to use a circuit tester, like part # PTW2993, to wire your trailer wires to a seven-way trailer connector, like part # A7WCB. Wiring by function is the best way to make sure you have the trailer connector wired correctly. Be sure you know what the black wire function is on the trailer. It will probably be for a twelve-volt battery or for reverse lights, but it could be used for something else. The location for the black wire in the connector is dependent upon the function of that wire.

I have attached a wiring article, see link, for you to reference when connecting the wires to the seven-way trailer connector.

expert reply by: John H