How to Wire 4-Way Round Pin Trailer Wiring Connector PK11409


I have a boat trailer with a flat 4 connector. One of the female connectors broke. I want to replace it with a round connector. If I buy a 4 round connector how do I know which wire to put in which hole? thanks.

Expert Reply:

There is not an industry standard layout for wiring the 4-Way round pin connector, but there is a layout that is most accepted.

If you you are looking at the front side of the 4-Way round trailer side plug, the top left prong would be used for right hand turn signal and brake function, the top right pin would be the left side turn signal and brake light function, while the bottom left would be used for the tail light function. The last pin, on the bottom right would be used for the ground wire. See the picture to the right for more clarification.

The standard 4-Way wiring colors are white for the ground wire, yellow for left turn signal and brake light functions, brown for tail light function, and green for right hand turn signal and brake functions. These wires would simply be installed in the back side of a 4-Way round connector like part # PK11409.

To wire your vehicle, you would match the wiring layout you created on the trailer by wiring a vehicle end 4-Way round connector like part # PK11410 as a mirror image of the trailer connector.

If you need some additional wire or would just like to replace your current wiring while you are changing out the connector, we offer bonded 4 wire # 16-4B-1 by the foot.

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