How to fix exterior LEDs on an enclosed trailer

Posted by Eddie Best January 29, 2025

Exterior LED lights on an enclosed trailer are essential for visibility and safety, especially when traveling at night or during adverse weather conditions. If these lights malfunction, it’s important to fix them promptly to ensure compliance with road safety regulations and to maintain your trailer’s functionality. This guide provides a step-by-step process to troubleshoot and fix exterior LED lights on your enclosed trailer.

Step 1: Gather Tools and Materials

Before beginning, collect the necessary tools and replacement parts:

  • Screwdrivers (flathead and Phillips)
  • Multimeter (for testing electrical connections)
  • Wire strippers and crimpers
  • Electrical tape
  • Replacement LED lights (if needed)
  • Heat-shrink tubing or waterproof connectors
  • Safety gloves

Step 2: Inspect the LED Lights and Connections

Start by visually inspecting the LED lights and their connections. Look for:

  • Broken or damaged lights: Check if the LED bulbs or lenses are cracked or waterlogged.
  • Loose or corroded connections: Examine the wiring for signs of corrosion, especially at connection points.
  • Physical damage to the wiring: Look for frayed or exposed wires that could cause shorts or interruptions in power.

Step 3: Test the Electrical System

To determine whether the issue lies with the LED lights or the trailer’s electrical system:

  1. Turn on the vehicle’s lights: Ensure the vehicle supplying power to the trailer is operational.
  2. Check the trailer’s wiring harness: Inspect the connection between the vehicle and trailer. Ensure the plug is securely inserted and free from debris or corrosion.
  3. Use a multimeter: Test for voltage at the light’s power supply. Set the multimeter to DC voltage and check if power is reaching the light. If no voltage is detected, the issue may be further up the wiring system.

Step 4: Repair or Replace Faulty Components

Depending on what you find during your inspection, follow these steps to fix the problem:

Repairing Wiring Issues

  1. Identify damaged wires: Cut out sections of damaged or corroded wires using wire cutters.
  2. Strip the wire ends: Use wire strippers to expose about half an inch of copper on each end of the wire.
  3. Reconnect wires: Use waterproof connectors or crimp connectors with heat-shrink tubing to join the wires securely. Heat-shrink tubing provides extra protection against moisture.
  4. Secure the connections: Wrap connections with electrical tape for added durability.

Replacing LED Lights

  1. Remove the damaged light: Unscrew or unclip the faulty LED light from its mounting bracket. Disconnect the wiring harness by unplugging it or cutting the wires (leaving enough length to reconnect).
  2. Install the new light: Connect the new LED light to the existing wiring. Match the positive and negative wires (often color-coded) to avoid polarity issues.
  3. Test the light: Before securing the light in place, turn on the power to ensure the new LED works properly.
  4. Mount the light: Secure the light to the trailer using screws or brackets, ensuring it is tightly fastened.

Step 5: Check the Grounding

Improper grounding is a common cause of LED light issues. Ensure that:

  • The ground wire is securely connected to a clean, bare metal surface on the trailer.
  • There is no rust or paint preventing a solid ground connection. Use sandpaper to clean the grounding surface if necessary.

Step 6: Test the Lights

After completing repairs or replacements:

  1. Reconnect the trailer to the vehicle.
  2. Turn on the vehicle’s lights and test all trailer functions, including brake lights, turn signals, and running lights.
  3. Confirm that all lights are operating correctly and at full brightness.

Step 7: Prevent Future Issues

To reduce the likelihood of future LED light problems:

  • Seal connections: Use heat-shrink tubing or dielectric grease to protect wiring connections from moisture and corrosion.
  • Inspect regularly: Periodically check the lights and wiring for signs of wear or damage.
  • Protect the wiring: Use conduit or loom tubing to shield wires from physical damage and the elements.
  • Avoid overloading the system: Ensure the trailer’s electrical system is not drawing more power than it can handle.

Conclusion

Fixing exterior LED lights on an enclosed trailer is a straightforward process that involves careful inspection, testing, and repair or replacement of components. By addressing issues promptly and taking preventive measures, you can ensure your trailer remains safe, functional, and compliant with road regulations. Regular maintenance and inspections will also help you catch potential problems before they become major repairs. For professional help we recommend Grizzly Trailer Sales.