Using a trailer every day can make your life much easier, whether you work in construction, agriculture, or others. Trailers allow you to carry heavy equipment, tools and numerous devices that would be very challenging to fit and carry in a vehicle. However, a utility trailer only serves a purpose when it has good wiring. In situations where this is not the case, you may have problems with lighting, brakes or some other part of the trailer. The biggest challenge here can be to figure out that the wiring is bad, because if you are not a professional you cannot notice the signs, even when they are pretty obvious. You can read and learn more about this topic below.

Why is trailer wiring important?


Take the example of a situation where the wiring of a trailer is bad and prevents the lights from working properly. This can be very dangerous when driving on the highway, as other drivers may overlook the fact that there is a trailer in the back of your vehicle. And that can put you and them in danger, whether you’re moving or standing. That is why it is necessary to make sure that things like this don’t happen to you.

The same story applies when bad wiring negatively affects the operation of the brakes. In the event of transporting a heavy load with the brakes on the trailer not working due to poor wiring, it will take much longer to stop compared to a situation where the trailer brakes are working properly.

As you can conclude, it is necessary to take care that the wiring on the trailer is always optimal, to ensure that all its parts are in good shape and that your trailer will not pose a danger to you or other road users.

How to know if your trailer wiring is bad


By monitoring the operation of the lights on your vehicle and trailer, you can easily conclude that there is a wiring problem and that it is necessary to do something to fix it. Some common signs that there is some wiring issue are as follows:

  • The lights on the trailer are dimmed or do not work at all
  • Wires are broken or there is a light around them
  • Certain light functions on the vehicle (for example, a turn signal) no longer work
  • The light functions on the whole vehicle do not work
  • When you turn on only the left or right turn signal, both turn on
  • Once you turn on the headlights on the vehicle you notice that the lights on the trailer have gone out
  • The light on the trailer stays on even when you switch off the vehicle
  • You notice that the reversing lights on the trailer have lost their function

There are many other signs that there is a trailer wiring problem. Therefore, we recommend that you, if you notice that the lights on the trailer behave differently than usual or generally seem suspicious, immediately seek the help of an expert and find out if everything is okay, or do it yourself if you know how.

How can you fix some common trailer wiring issues?


The first step in determining the presence of wiring issues on your trailer is to test it separately and then the vehicle itself. Otherwise, you might be confused and go to the wrong side when it comes to drawing conclusions. Begin the troubleshooting process by testing whether all functions are correct. In this part of the task, you will need the help of a friend whom you will ask to turn on the lights, so that you can follow what is happening and conclude where the problem might be.

The next step is to check that all the wires are well connected, because sometimes this is the reason why your trailer is not working properly. Although most wire colors are standard, we suggest that you double check which wire determines which function. Once all the wired connections are correct, all parts of the trailer will work properly.

Ground connections are the following that you want to check. It is necessary to inspect your vehicle in the ground area and see if corrosion has accumulated. If this is the case, it is important that you clean everything thoroughly so that your truck can continue to operate smoothly. Then move on to the trailer and its ground region.

And finally, check what is the maximum amperage that the harness can withstand and conclude if it is overloaded. If you notice that the circuit has more current than recommended, it is necessary to unload it as soon as possible. Failure to do so may result in overheating, melting and damage. If possible, try to minimize the energy consumed by the vehicle to prevent overload and short circuits.

Ask for help


If you are unfamiliar with this area and are unsure whether you would know how to perform the troubleshooting process in the right way, we suggest that you consult an expert. Why would you do this alone, if you have a car electrician who can do it for you.

In the event that your car electrician determines that there is a problem with the wiring level, it is necessary to solve it as soon as possible, without driving a trailer during that time. There are many online sources where you can find a large selection of wires, including trailer ones. Also, you can learn more about these wires and understand their importance in the operation of your trailer at


Using a trailer can be very practical, but only if it is in good condition. In cases where there is a problem with the wiring, this can have a very unfavorable effect on the operation of the trailer and pose a danger to both you and other road users. If you notice that there are some problems with the lighting, it is necessary to do a troubleshooting process on the trailer and the vehicle in order to conclude what the cause is. And in case you are not skilled in this area, you can always contact an expert to help you determine what your trailer problem is and fix it for you.