New Wiring for a 35 Foot Long Gooseneck Trailer with 4 LED Tail Lights

Question:

Hello I need to rewire a 35 foot gooseneck trailer. The original wiring is a cobbled mess of 3 different harnesses. The tail lights are 4 3-wire led type and the marker lights are 2 wire led. How should this be wired and function? I have this on a 2004 f350 truck 7 pin connector with a electric brakes and a brake controller. A diagram would be really helpful, Thanks!

asked by: Jay

Expert Reply:

I have included a couple of links to the right that should help out a lot. One of the links covers everything you ever wanted to know about trailer lights, including where they need to be and what types based on the length and width of a trailer. The other does include some wiring and connector diagrams that should be helpful.

It sounds like in addition to the lights you would benefit from a new 7-Way trailer connector such as # 50-67-103 which is 15 feet long(and the longest I have), so it will get you close. Then you can use as much jacketed 7-Wire, # DW04914-1, as you will need to reach all of the lights. The wire is sold in increments of 1 foot. so for another 15 feet for example you would enter 15 in the quantity box.

It sounds like each tail light has one wire for brake lights/turn signals, one wire for running lights, and one wire for ground. And the marker lights have power and ground. This is all common so it doesn't seem like there is anything strange.

expert reply by: Michael H