Different color glue spool, more convenient assembly

 How to solve the common trailer wiring problems

First, test the trailer first to eliminate common problems. You must determine if there is a problem with the tractor or trailer by analyzing the separate wiring systems in the manageable portion, not all at once. If you start testing when you connect the truck to the trailer wire spool, you won't know what the problem is.

The following step-by-step guide will help you troubleshoot your trailer wiring. Whether you have a 4-way plug, need to analyze a ground connection, or have an overload situation, there is always a solution. Small fixes like this are easy to perform and require nothing more than time and a few tools. As soon as you start to encounter more complex problems, you should allow us to step in and help.

1. Test for correct functionality
For 4-way plugs, use a 12V bonded trailer wire to check the function of the vehicle lights. Ask someone to help use a different light so that you can focus on watching in the back. But before you perform any tests, remove the fuse from the power supply for a few minutes and reinstall it. If the power reading for any light function is incorrect, test the connection to the converter box. If the light wiring function is correct, you can check the trailer wiring system.

Behind the converter box, check if the signal is entering the converter box from the truck or car. The green and yellow lines on two-lane vehicles should indicate turn signals and brake lights. On third-line cars, the red line has brake lights, and yellow and green are used for turn signals. If there is no proper power supply for any light function, look for the following: loose connectors or wires on the plug in harness, missing fuses or relays; The ground connection on the manual wire harness is weak or loose; Wires connected to the wrong part of the truck.

2. Verify that the cable connection is correct
For hardwire installations, make sure each wire is connected to the correct location. Standard wire colors exist, but if your system changes, make sure to check the connection against its functionality. If your vehicle combines brake lights and turn signals, your brake lines will be grounded in white. The 12V power cord should be connected to the positive battery terminal of the car. If your trailer has a 5 route bundle wire, make sure the fifth wire of the truck is connected to the reverse light circuit.

Look at the following checks you can do when installing the plug-in:
Fix the connection between the 12V power cord and the vehicle battery while checking for a blown fuse.
If you use a factory trailer pack wiring harness, make sure your vehicle has a trailer pack.
Certify that the part number is consistent with the correct make, model, and year of your truck.
Verify that the harness connector is on the right side of the vehicle, the green wire is on the passenger side, and the yellow wire is on the driver's side.
Make sure the connectors are stuck together by removing and reconnecting them.
Check connectors for loose or damaged wires, loose or bent pins, and damaged lock plates.
You can also perform continuity tests. To troubleshoot the trailer wiring, connect the jumper to the connector pin and connect the continuity tester to the system socket. Continuity tests can help you see if there are any broken wires. Select a color wire in the socket and find the same wire on the front of the connector. Clip one end of the jumper to the connector pin and the other end to the continuity tester.
Detector in socket. If your trailer lights fail, trace the wires and check for breaks. Cut any faults found, then solder to new joints and repair insulation with heat shrinkable tubing.

3. Check the ground connection
On your truck, check the ground area for corrosion and paint buildup. Clean the area as needed until you reach a clean metal surface or can replace any corroded ground screws.

If you have factory ground screws, ensure that other ring terminals are not stacked under the ground. If yes, move the ground of the harness to a different position or toward the bottom. Finally, disconnect the ground wire and connect it to a wire connected to the car's negative battery terminal. If it solves your light wiring problem, you can fix the cable in place.

For your trailer wire, it is essential to check your ground system. Make sure the ground wire is connected to the trailer frame. If the trailer has a tongue fold, make sure it is attached to the structure behind the tongue. If the ground wire is connected to the aluminum area, you can also transfer the ground wire to the frame.

4. Look for overload
An overload occurs when a circuit is overloaded with more electricity than it can handle, which can lead to overheating and melting. Note the maximum current rating of the harness and compare it to the current of the trailer light. In some cases, you can reset the device by removing the fuse and leaving it in place for a few minutes. Use the circuit tester to check the function of the 4 way plug, do not insert the trailer before testing.

If each feature is present after the reset process, your trailer may short-circuit. If the current of the trailer light exceeds the capacity of the harness to handle, remove the bulb from the additional gap light and connect the trailer. If the wiring harness works without any bulbs, it indicates an overspend on the number of lights on the trailer. Remove gap lights and replace them with LED versions to reduce power consumption.

5. Other possible trailer light wiring problems
Over time, these elements can overtake your trailer and corrode in different areas. Make a note to check for corrosion, which may look green or white. Replace the plug or clean it with battery terminal cleaner. You need to complete this step after you have checked the car's lights and the trailer's lights still appear dim or not working. You can also spray the connectors with an electric contact cleaner and clean each stylus with a fine wire brush. This will also help create a stronger connection between the wires.

When corrosion reaches the socket, it may cause your lights to not work. Another cleaning method involves using # 220 sandpaper to remove corrosion. If you can't get your fingers into tight Spaces, heat glue a strip of sandpaper to the 3/8-inch pin. Clean each spot by rotating the dowel and pushing it from side to side. After that, apply a little insulating grease to the contacts and replace the bulb. If your lights are still not working, check the mounting bolts to ensure they are in clean contact with the trailer frame.

If the lights are grounded through the installation hardware, you should also ensure that the non-aluminum installation area is clean and free of paint. If the surface is aluminum, connect the ground wire and lamp post to the frame. Last but not least, check that the bulb is working properly and replace it as needed. Turn it on and on -- it's as simple as that. If any of the light bulbs in the trailer break or go out, remove the old bulb and install a new one. It can happen with any light, including running lights, flash lights, and parking lights.

If your trailer wire spool has more advanced tow line problems, you can rely on a tow expert. If the corrosion is too great to sand out, or if you need brand new wiring harpoons, including connectors, lenses, lights, and other details, maybe this is a relatively cumbersome thing to do, but the importance of trailer spool is something I think every tow truck driver knows well. The choice of good quality tow line is one of the conditions to ensure our driving safety.

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