Basic 4 Wire Trailer Wiring Diagram

I have a separate wire for brake lights.

Basic 4 wire trailer wiring diagram. Various connectors are available from four to seven pins that allow for the transfer of power for the lighting as well as auxiliary functions such as an electric trailer brake controller backup lights or a 12v power supply for a winch or interior trailer lights. To wire a trailer the first step is to determine what components on the trailer need wiring. Start by cutting the white wire and attaching it to the trailer frame. Of course the more items you have the more poles you will need on your connector.

Installing the 4 pin trailer wires. Trailer wiring diagrams 4 way systems. Trailer wiring diagrams trailer wiring connectors. Trailer wiring kit and supplies.

While the basic configuration is a 4 way flat connector that features one female and three male ends you may come across connectors with up to seven pins for additional functions that require wiring including electrically actuated brakes power source for a winch etc. Right turn signal stop light green left turn signal stop light yellow taillight license side marker brown and a ground white. Blue electric brakes or hydraulic reverse disable see blue wire notes below in the trailer wiring diagram and connector application chart below use the first 5 pins and ignore the rest. I have had to mess with trailer wiring for years once or twice a year anyway.

If your vehicle is not equipped with a working trailer wiring harness there are a number of different solutions to provide the perfect fit for your specific vehicle. Standard color code for wiring simple 4 wire trailer lighting. The 4 way above is a basic and most common scenario but what if you have more items that require wiring. You must check the trailer manual to see if the wiring is correct but normally the white wire is called the ground wire while the brown wire is used for tail lights.

Complete with a color coded trailer wiring diagram for each plug type this guide walks through various trailer wiring installation solution including custom wiring splice in wiring and replacement wiring. The basic purpose remains the same whether your truck and trailer is using a 4 way 5 way 6 way or 7 way connector. 1 4 wire the first 4 pins white brown yellow green just like the 4 pin connector above. The most common wire thickness for a trailer is 16 gauge but i bought thicker wiring for added durability.

4 way flat molded connectors allow basic hookup for three lighting functions. Yellow and green are for left and right turns and braking. Buy a 4 pin wiring kit with wires at least twenty feet in length so it s long enough for your trailer. By law trailer lighting must be connected into the tow vehicle s wiring system to provide trailer running lights turn signals and brake lights.