trailer light wiring question

[Crow Hunter]

I have a utility trailer and I want to replace the light plug. The plug I have has the typical four pins, but there are five wires going into the plug. I asked someone at a store where they sell replacement plugs and he told me I have to run another brown wire to be able to replace this plug with a standard four wire/four pin plug, which did not make sense to me, since there is already one more wire than normal. Any ideas how this is wired? I have to assume that two wires connect to one pin? I could cut the plug off and ohm it out I suppose. Thanks for any insight.

[Macgyver55]

If I understand you correctly, the extra wire (if it is brown) is normally for running (tail) lights so you are able run a separate wire to each tail light instead of having to make an extra connection some where else to run to the opposite side tail light. You can replace it with a standard plug by simply connecting the 2 brown wires on the trailer to the single brown on your new connector.

[Esox_Magnum]

Should have green, yellow, brown//yellow, green/yellow and white... Whites ground, green and yellow are tail/marker lights other 2 are turn signal/break lights... I hope I got that right....

[john.wells]

I assume you are talking about the connector that goes to the vehicle. For what it is worth, in a normal configuration, brown is for your running/parking lamps, yellow is dual purpose for left signal and brakes, green is dual purpose for right signal and brakes, and white is for chassis ground. Do you have electric brakes or separate brake lamps? This could explain the fifth wire. Usually if you have an electric brake system on the trailer you would see a 7 pin connector (round) in use. Without knowing more, it is hard to tell what you need to do. Hope this info helps

[john.wells]

nope.

[Crow Hunter]

No electric brakes, no separate brake lamps. this is just a 5X8 utility trailer. The five wires are white (ground) yellow/brown, green/brown, yellow, green. I will likely just cut the connector off and ohm it out, two of the wires have to be connected to one of the four pins.

[SkunkedAgain]

Did you read the Trailer Wiring 101 thread stickied to the top of Expert/Equipment forum?

[Macgyver55]

My guess is that the yellow/brown and the green/brown will both go to the solid brown on the connector. The solid green is right turn and brake light, and the solid yellow is the left turn and brake light. The yellow/brown and solid yellow will go down one side of the trailer to the left tail light, and the green/brown and the solid green will go down the other to the right tail light. I think they do it that way to supposedly make it less confusing, but it makes it more confusing in some ways.

[Crow Hunter]

Yes, I just spotted the trailer light wiring tutorial and have been reading it, very informative. Thanks for all the help, guys.

[Jeremy airjer W]

My guess is that the yellow/brown and the green/brown will both go to the solid brown on the connector. The solid green is right turn and brake light, and the solid yellow is the left turn and brake light. The yellow/brown and solid yellow will go down one side of the trailer to the left tail light, and the green/brown and the solid green will go down the other to the right tail light. I think they do it that way to supposedly make it less confusing, but it makes it more confusing in some ways.

Agreed. the two brown wires are so you can run browns to both sides of the trailer instead of using a single brown that will need to be run around the trailer to connect the side markers and the tail lights. most of the time the single brown wire is spliced several times to accomplish this. The duel brown wires do the same thing but are spliced in the connector to make things easier.