How to Hook Up a Trailer Light

How to Hook Up a Trailer Light
There are several ways to connect a vehicle to a trailer. A vehicle that has a tow package will have a trailer light connection but the connection must be compatible with the trailer's connection. If your vehicle does not have a connection or a tow package, you must install a tow bar and wire in trailer lights. Wiring a connection should only be attempted by those with electrical experience. The task can be completed quickly by a professional but improper wiring can compromise the entire electrical system.


Difficulty: Moderate

Things You’ll Need:
  • Vehicle connection
  • Trailer connection
  • Connection adapter
Step 1
Determine the shape of the connection on your vehicle. It will either be flat, round or square. If the shapes match, the number of male and female inserts will determine compatibility.
Step 2
Determine the number of male and female inserts on each each connection. If the shape and inserts match, make the connection by inserting the male end into the female end. The connection will either have a four-, five-, six- or seven-way connection. The four-way flat is the the most common trailer light connection but large trailers are likely to have a five-,six- or seven-way round.
Step 3
Use an adapter to make connection when the ends do not match. Adapters can be purchased to match most connections. You must determine the type of connector on the vehicle and the trailer before purchasing the adapter.
Step 4
Connect the trailer lights directly or through the adapter. Start the vehicle and ask another person to check the trailer lights.
Step 5
Press the break and confirm the brake lights function on the trailer. Use the right and left blinker and confirm the blinker lights correspond with each direction. Use the hazard lights and confirm that the left and right trailer lights are blinking.

Tips & Warnings

Check the trailer lights every time you make the connection. Keep any adapters used in the vehicle or on the trailer when you are not towing. This will prevent you from losing the adapter.
Do not drive without the trailer lights connected. Not only is it illegal but it is extremely dangerous. If the lights do fail, use hand signals until you can access a mechanic or automotive store and fix the issue.

Article Written By Zach Lazzari

Zach Lazzari is an outdoor writing specialist. He has experience in website writing as well as standard newspaper writing. He wrote an outdoor column for the Silver World in Lake City, Colo., and articles for Lazzari is currently completing his bachelor's degree online through Arizona State University and lives in southwest Montana.

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