Replacing 5-Way Trailer Harness That Has 7 Wires

Updated 03/10/2020 | Published 03/09/2020

Question:

Replacing a 5 pin wire harness and noticed the old one has 2 browns and 2 whites with 7 wires total and the new one has only 5 wires.What do I do with the extra wires just connect them together?

asked by: Anthony L

Expert Reply:

When a 4-Way or 5-Way pin wiring harness for a trailer has more wires than pins, like the Optronics # A40W5B, it just means that the manufacturer is trying to make it easier on the installer. In your case it sounds like your trailer has 2 ground wires and 2 running light wires that run down either side of the trailer. If this is the case then all you have to do is splice the browns together and the whites together with your new harness and everything should work great!

I have attached a link to a helpful article on installing a 5-Way trailer harness that you can check out as well.

expert reply by: Jon G