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The Best Trailer Light Harness

Last updated on May 17, 2022

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Our Picks For The Top Trailer Light Harnesses

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Product Overview
Key Takeaway
 Runner Up

Miady 4-Way Flat Plug Connector Trailer Light Harness

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4-Way Flat Plug Connector Trailer Light Harness

You can use this trailer light harness for a variety of trailers such as boat trailers and horse trailers. It has a wishbone style wiring setup design. The wiring has 25 feet of length.

Overall Take

Wide ApplicationThis trailer light harness can be used for a number of different trailers.

 Strong Contender

WoneNice Waterproof LED Light Kit & Trailer Light Harness


Waterproof LED Light Kit & Trailer Light Harness

This set includes a trailer light harness, two combination tail and brake lights, two marker lights and a license plate bracket. Everything you need to install the set is also included.

Overall Take

Complete SetThis trailer light harness also comes with lights.

 Also Great

SUZCO 4-Way Flat Plug Color-Coded Trailer Light Harness


4-Way Flat Plug Color-Coded Trailer Light Harness

This trailer light harness is straightforward and comes with wiring instructions. There is adequate length in the wire. The harness is corrosion resistant.

Overall Take

Straightforward ProductThis trailer light harness comes with easy-to-understand instructions.

Buying Guide

If you are towing a trailer behind your vehicle, one of the most important gadgets you will need is a trailer light harness. This gadget is a wire that goes from the back of your vehicle to the trailer, connecting their electrical systems. This way, your vehicle supplies power to the trailer’s lights and ensures they are synchronized with the vehicle’s taillights. In some cases, the trailer light harness can also connect the trailers brakes and auxiliary power with your vehicle.

Without this important gadget, you are not ready to take your trailer out onto the road. If you don’t use a trailer light harness, drivers on the road will not be able to see the lights on your vehicle as they may be blocked by the trailer. This can cause dangerous driving conditions as the drivers may not be able to see when you are braking or where you are in low light conditions. This is why using a trailer light harness is the law – and common sense.

When getting a trailer light harness, it’s important to consider what the plug or socket type is, how many pins are on the harness and what the wiring configuration is. There are a few different types of plugs and socket connections, such as flat, circular and RV blades. When it comes to pins, most trailer connectors come with between four to seven pins. The number of pins it includes corresponds with the number of roles the harness has. One pin is the grounding system and the rest of the pins have different functions.

What to Look For

  • If you want to protect your trailer light harness and ensure it lasts for years, it’s important to keep it covered as much as possible. This can reduce corrosion and make the connectors more secure. Some people further protect their trailer light harness by applying Dielectric grease on the connectors. This helps to keep any moisture off of the trailer light harness. If your live in an area that gets a lot of rain and snow or you use the trailer for a boat, it’s important to take active steps to avoid corrosion.
  • Some trailer light harnesses are made for specific types of trailers while others offer a wider application. For example, some can be used for boat trailers, horse trailers, motorcycle trailers, ATV trailers and other types of trailer hitches.
  • Compatibility is key, so be sure to carefully check what type of trailer light harness your need for your vehicle and for your trailer. If you use multiple vehicles to pull the same trailer on different occasions, this is another element to keep in mind when checking compatibility.
  • How long of a wire do you need to connect the vehicle to the trailer? Many trailer light harnesses are either four feet or six feet long, but some actually go to eight feet long. This offers you a lot more flexibility.
  • Some trailer light harnesses actually come with a full kit which includes the tail lights and brake lights. This is what you need if the trailer doesn’t have its own lighting system already in place.

More to Explore

Safety is key when you’re pulling a trailer behind your tow vehicle. Once you’ve installed the trailer light harness, get someone to help you check that it is working. Sit in the tow vehicle and get your partner to confirm that the running lights, brake lights, turn signals and hazard lights are working properly on the trailer in connection with your tow vehicle. You will also need to check the connection wires to make sure they are loose enough for you to make any turns without the wires getting disconnected from the tow vehicle.

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