weekly trailer wiring question

[ssaamm]

Last fall my trailer lights would work if it I tightened two cable ties around the connectors. Otherwise, if I hit a bump the lights would go out. I was going to be handy for a change. Went out and bought Trailer to Vehicle connector. It had the three male and one female leads like the existing one. I was ready to cut the old one off when I realized that there was an extra brown wire on the one attached to the trailer. I figured I would simply cut 'em off one at a time and splice the new one into place. This extra wire is confusing me. Any insight would be great. Thanks. The cable ties are cheap and seem to work, but this shouldn't be that hard to figure out. thanks

[Jeremy airjer W]

Brown is the running lights. As long as there are four connectors and not five you'll be fine. I'm guessing that that manufacturer split the brown wire at the connector so that it could be run down both sides of the trailer.

[Bandit]

airjer is correct. the brown is for the runniing lights, just connect both browns from the trailer to the brown on your new harness.