How to Install Trailer Lights

LED lights are a fantastic upgrade for any trailer with their improved visibility, reliability, and longevity. With this guide, you’ll be well on your way to making your trailer safer and more modern. 

Enhance your road visibility by utilizing LED tail, brake, turn, and reverse lights for trailers. Proper lighting on your truck promotes safety, and incorporating LEDs also provides additional advantages. LEDs have a significantly longer lifespan compared to traditional filament truck lights. Moreover, they offer an instant-on feature, enabling drivers behind you to react promptly and minimizing the risk of hazardous collisions.

These lights are typically mounted at the rear of the trailer, as far apart as possible, at the same distance from the trailer's centerline (essentially the same distance apart from the trailer's center, aka parallel) and the same height above ground (15-72" inches generally).

We offer an extensive range of DOT-compliant lights in various styles, shapes, and colors, readily available for purchase.

Marker and clearance lights serve multiple purposes for your trailer. Not only do they enhance visibility on the road, but they also provide unique advantages compared to other types of lights. LED lights, for example, consume less power, resulting in increased durability and emitting a significantly brighter light than traditional lights. Additionally, our wide range of DOT-compliant shapes and colors ensures you can find the ideal style and safety options for your needs. For rear-side marker lights, mount one on each side of the trailer. Most of the time, they are mounted about 15 inches or more above the ground. For front-side marker lights,  you must have one on each side. These are also typically mounted 15 inches or more above the ground.

Before you begin, you will need to gather a few materials in addition to your trailer lights. Here is a list of the essential items:

• Electrical Tape
• Tools (Wire Cutters, Strippers, and a Screwdriver)
• Drill (optional, if holes for lights/mounting brackets are not pre-existing)
• Wire Connectors or Soldering Equipment (optional for securing wire connections)
• Heat Shrink Wraps
• Wire Nuts

Before you begin working, ensure your trailer is safely parked on flat, level ground and your vehicle's engine is turned off. Disconnect any power sources and ensure the trailer and lights are cool to the touch to avoid any potential injuries.

First, remove the existing lights from your trailer. Keep the screws or bolts if they are in good condition; they can be reused to install the new lights. If you have a light that is mounted with a rubber grommet (recessed mount), you can use a screwdriver to pry out the light and grommet from its cutout to disconnect the plug/wires.

Next, if your existing lights do not have a connector to disconnect their wiring, you'll need to cut the wires connecting to the old lights. It is better to cut closer to the light end to leave as much wire length as possible. Once the wires are cut, use a wire stripper to remove about 1/4 inch of insulation from each wire end.

If the old lights were connected with plugs and weren’t damaged upon removal, and there’s no damage to the wiring harness, you can skip this step and simply just attach your new LED trailer lights to the existing connection.

Now it's time to connect the wires. Each LED light will usually have a ground wire (often white), a tail light wire (often brown or black), and a turn signal/brake light wire (often green for the right and yellow or red for the left). Attach the corresponding wires from your trailer to the wires on the LED lights.

If the light being replaced has a plug that is in good condition and matches your new light, you can plug your new light into the existing connector.

To secure the new connections, use butt/bullet connectors or solder the wires and then cover them with heat-shrink tubing.

LED lights need to be grounded properly to function. Most trailer harnesses have a white wire that is used for grounding. The white wire should be connected to the metal frame of your trailer. If you have a single-wire, self-grounding light, this means it grounds itself through the mounting hardware (e.g. screws).

Attach the main lights to the rear of your trailer using the provided screws or your old ones. If required, drill holes for the screws. Follow the same process for any additional lights.

Generally, if the light is recessed/grommet mount, you will already have the needed cutouts for replacing the lights, but if it is a new trailer or you are changing the style of lights, you will also need a saw for making a cutout for a recessed or grommet mount light.

Once everything is installed, it's time to test the lights. Hook up your trailer to your vehicle, turn on your vehicle's lights, and then walk around the trailer to check each light. Test the turn signals and brakes as well. If any light does not work, check the wiring connections and make sure the light is properly grounded.

Remember, safety should always be a priority. If you're not comfortable doing this yourself, or if the lights are still not working after installation, don't hesitate to contact a professional.