White = Ground (See White Wire Notes below.)Ģ. Lighter Duty Trailer (No Brakes) = Use a 4-Pin Connector.ġ. Small utility trailers, light boat trailers, little campers, off-road trailers and many more use this traditional 4-Pin Flat connector. It’s the most common style for “consumer” type trailers. Trailers that use this are usually fairly light weight and don’t have brakes or other power accessories. The most common 4 wire connector is the 4-Pin Flat Connector as shown here. 4 wires will give these functions, so the simplest scheme is a 4-pin connector. It can get confusing, so if you don’t already have a specific standard in mind, follow these.Īt a minimum, all trailers need at least 4 functions: Tail lights, Brake lights, Left & Right signals.
That said, for specific situations, there are industrial standards with different connectors and wire arrangements. We recommend these standards because they are pretty universal. The following trailer wiring diagram(s) and explanations are a cross between an electrical schematic and wiring on a trailer. Some brakes need electricity too - to actuate electric brakes, or to disable hydraulic brakes when backing up. Some also need side markers and running lights. To start, every trailer needs lights - brake lights, turn signals, and tail lights. The approach for you depends on your electrical needs. Follow these guidelines and make it right! Each standard has it’s different purpose, so please don’t just make it up as you go.
There are several standards for trailer wires, and if you search, you’ll find a different Trailer Wiring Diagram for each. And, a little more information to make sure I get it right! Yikes! Where do I start? I need a trailer wiring diagram. And, so many kinds of trailer wiring connectors.