Learn how to install or repair a Trailer Connector using these Trailer Connector Wiring Diagrams

If you’re wiring in a trailer connector from scratch, the connector you choose depends on the lights on your trailer. If your lights have reverse (backup lights) or electric trailer brakes, or an auxiliary power socket, you’ll need a connector with more wires. These trailer connector wiring diagrams cover the vehicle and trailer side views starting with the simplest 4-wire designs all the way up to the 7-wire designs.

At the very least, you need a minimum of four wires to meet the basics of trailer wiring

Left turn
Right turn
Brake lights
Ground for all of the above

Trailer wire color standards

GREEN is used for the right turn signal
YELLOW is used for the left turn signal
BROWN is used for tail/parking lights
WHITE is used for the ground connection

Two 4-wire trailer connector types

Choose from two types of 4-wire connectors: flat and round.

Trailer connector wiring diagrams for the 4-wire connectors

Posted on February 12, 2024 by Rick Muscoplat