Types of Trailer Wiring Harness You Should Know
                     Types of Trailer Wiring Harness You 
Should Know
Types of Trailer Wiring Harness 
You Should Know
A trailer wiring harness is a piece of wiring connector located at the back end of a 
vehicle. It allows the vehicle's electrical system to connect with the trailer. The wire 
harness trailer hitches to the vehicle's existing wiring and provides a standard 
connection. 
When you tow a trailer, it is necessary to use wiring to connect the lights and auxiliary 
power to the vehicle's electrical system. Without a Trailer wiring harness, your trailer 
lights will not work correctly, and you will not be able to use turn signals.
Different Types of Wiring Harness
Standard trailer connectors have four to seven pins. Each pin serves a particular 
purpose. They are arranged from left to right in a specific order. The power pins can be 
found at the top, while the grounding pins can be at the bottom.
Types of Trailer Wiring Harness 
You Should Know
4-way Wiring Harness- This harness is ideal for boats and light-duty trailers. The 
colour-coded wiring harness helps ensure that the wires match correctly. Each wire 
has a unique function. 
The left turn signal light wires are wired using a yellow wire, and the right turn signal 
lamp is wired using a green or brown wire. The light assembly must be grounded to 
the trailer. 
The fifth wire of the trailer wiring harness activates the trailer's electric brakes. To 
ensure that the trailer's brake lights are lit when the vehicle brakes, the fifth wire of 
the trailer wiring harness is often connected to the brake light.
6-way Wiring Harness- This is the same as the four-way and five-way wiring 
harnesses but features the seventh wire for additional capability. The sixth wire is 
typically used for charging the trailer battery, and it is also used as a fused battery 
lead.
Types of Trailer Wiring Harness 
You Should Know
Flat Trailer Wiring Harness- This is ideal for turn signals, brake lights, and other trailer 
lights. It features a 4-pin plug for easy installation. It also has a wishbone shape, 
making it convenient to install. 
Its 16-gauge wire can connect to most standard trailer wires that weigh just 4.8 
ounces. The flat trailer harness can be installed in minutes, making it the perfect 
solution for trailer lighting.
Choosing the correct trailer wiring harness for safety and efficiency is crucial. Visit 
https://www.trailers2000parts.com.au/ to find your trailer's right, superior-quality 
wiring harness. 
Types of Trailer Wiring Harness You 
Should Know