Why are my trailer brakes not working?

In this blog post, we will answer the question: “Why are my trailer brakes not working?” We will also discuss a few tips to fix non-working trailer brakes. Additionally, we will talk about a few tips to test the electric brake wiring. By the end of this post, you will get to know how to troubleshoot your trailer brakes not working.

Why are my trailer brakes not working?

Your trailer brakes might not be working for the following reasons

  • Common electrical problems
  • Weak brakes
  • Locking brakes
  • Harsh brakes
  • Surging brakes
  • Dragging brakes
  • Broken brakes

Common electrical problems

  • Trailer brakes not working is a common issue that is often found in trailers. In most cases, travel trailers have electrical brakes. The newer models of travel trailers are equipped with electric brakes and one electrical problem is pretty common.
  • Some of the most common electrical problems are low amperage flowing to the brakes due to low voltage. No voltage problems and poor electrical connections are also common.
  • Many trailer owners have complained about electrical problems and these come due to open circuits, weak connections, broken wires, blown fuses, insufficient wire size, etc.
  • Another common reason can be improper functioning of the controllers or resistors that are connected to the trailer.

Weak brakes

  • Weak brakes have also been noted to be an issue for trailer brakes not working. This takes place after several years and there are chances of the breaks to get weak.
  • The trailer brakes can become weak due to worn linings or magnets, improper synchronization, overloaded trailer, corroded connections, and more.
  • It is required to check the brakes of the trailer often and get them replaced when required. Trailer brakes can become weak if the trailer is used often.

Locking brakes

  • Locking brakes are yet another issues that have occurred for the trailer brakes not to work properly. This is pretty common as the brakes in a trailer can get locked often.
  • Locking brakes take place due to under adjustment, faulty controller, loose, bent, or broken brake components. Locking brakes can also prop up if there is insufficient wheel load and out-of-round brake drums.

Harsh brakes

  • Harsh brakes are similar to locking brakes and these causes can also be the same. Harsh brakes can be tight and it might be hard to even apply harsh brakes while driving due to the pressure. However, there are several ways to get this back in form.  

Surging brakes

  • Surging brakes are also caused due to grease or oil on magnets or linings. It is also caused due to faulty controllers or out-of-round cracked brake drums.
  • Surging brakes need to be replaced and it is a pretty common issue that is found in most travel trailers.

Dragging brakes

  • Dragging brakes are also common in most travel trailers. This issue is sure to come up once in a while. Dragging brakes are caused due to over adjustment, and incorrect brake components.
  • Dragging brakes can also be caused due to a faulty breakaway switch, bent spindle, loose wheel bearing adjustment, incorrect brake components, etc.

Broken brakes

  • Broken brakes can get worn out and it is pretty common. However, broken brakes can be a dangerous situation and it can take place suddenly while driving.

Those were some of the common issues for trailer brakes not working. The trailer brakes are equally important when towing and non-functioning brakes can be dangerous. It is important to keep a check on the brakes of the trailer as much as possible. Sending your trailer for regular maintenance will help you keep your trailer brakes in good condition.

Tips to fix non-working trailer brakes

While it is common for your trailer brakes not to work, it is also easy to fix these trailer brakes with a few steps. Here are a few tips to fix non-working trailer brakes.

Replace the wiring

  • The first and most important part is to check the connections. In most cases, the poor connection might be an issue even with advanced brake controllers. Be sure to check the connections and ensure that there are no damaged wires.
  • It is also important to check the circuit and examine all the parts where wires are involved. Be sure to check if all wires are connected to the right location.
  • Ensure that the brake wire is grounded in the right color. In many situations, overload can cause damaged wires. It is essential to get the wires replaced. Be sure to replace all the wires and make sure that you replace everything together.

Check the voltage

  • Proper flow of voltage is pretty important, especially in an electric trailer brake controller. Low voltage issues come due to open circuits and this must be rectified as soon as possible. Use a voltmeter to check the voltage. The voltage normally begins at zero and increases to 2 volts.
  • You can also check the manual if the controller does not produce any voltage. The voltage of the controller must be equal to the voltage applied to the brakes.

Get rid of corrosion

  • It is also important to get rid of corrosion, especially on connector pins and inside the plug. This can accumulate dirt over time and it must be cleaned often.
  • Make sure to use WD-40 to remove all the dirt and any other corrosion or resistance. You can also use the solution on the trailer plug.

Check the trailer connector

  • The trailer connector is also equally important and the flow of power to the connector plays a vital role. Ensure to check the trailer connector to see if there is enough power.
  • You might need help for another person while checking the trailer connector. Make sure you hold the brake pedal when you probe the connector for power.
  • Be sure to check the junctions in the wire at the back of the controller.

Check the trailer breakaway switch

  • The trailer breakaway switch is another crucial part that needs to be looked into. Trailer brakes might also apply on their own and this will not cause the brakes to release.

Get the right settings in the controller

  • For electric trailer brakes, you will need to get the right settings in the controller. Be sure to get the right adjustments on the brake controller. Some brake lockup issues can be avoided by preventing electric brake lockup.

Get rid of grease

  • Grease can accumulate on the brake shoes with ease and this can cause various issues. It is important to remove the grease on the brake shoes. It is also good to check if the brake shoes are poorly adjusted.

Tips to test electric brake wiring

  • Electric brake wiring is the most common issue and it is important to know the steps to test the electric brake wiring. Here are a few steps to follow to test the electric brake wiring.
  • The test light will need to illuminate for the trailer connector to work in order. If the light does not illuminate, there is a fault between the wiring, connector, and the electric brakes.
  • Reassemble the trailer connector to the tow vehicle and depress the brake pedal.
  • Get a hold of the wire that controls the electric brake. Connect it to the ground clip and test the light to the trailer’s frame.
  • Examine the wiring and look for damage or deep cuts in the insulation. Repair and replace all wires if necessary.

Those were a few steps to test the electric brake wiring. By doing so, you will get to know where the damage lies. These tips might come in handy with electric brake trailers. Be sure to get your trailer brakes serviced every couple of months to avoid any confusion. Never work on the brakes or try to solve the issue on your own. Always consult an expert to get the task complete.


In this blog post, we have answered the question: “Why are my trailer brakes not working?” We have also discussed a few tips to fix non-working trailer brakes. Additionally, we have talked about a few tips to test the electric brake wiring. Leave us a comment below to let us know if you have faced any issues with trailer brakes not working.



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