Understanding Service Trailer Brake System

Summary

Every time the brake pedal is depressed, the trailer service brakes will engage. The towing vehicle frequently has a hand valve installed on the steering wheel or instrument panel so the driver can use the trailer service brakes independently of the towing vehicle’s brakes.

The “Service Trailer Brake System” message on your dashboard means there’s an issue with the electrical wiring of the trailer brake or module, disrupting the power supply between the truck and the trailer.

You should maintain your trailer brake system if you always tow a trailer with your truck. It must operate without error for your safety. It also includes a breaker switch to open and close the ignition coil’s primary circuit, except for certain modern engine systems.

The reasons and causes why a service trailer brake system light comes on include a blown fuse, faulty brake light switch, bad master brake cylinder/sensor, Broken trailer brake control switch, and bad wiring. Learn about ABS sensors here!

Understanding ABS sensor

Now, let’s go deep to explain what a service trailer brake system is, its warning message, reasons why its light comes on, and how to reset it!

trailer brake

Contents

What is a trailer brake?

The trailer brake controller is a module or device installed in a vehicle to help the driver control the speed and stopping of the trailer. It is mounted on the driver’s side dashboard and activates in proportion to the vehicle’s brake or at a time-delayed frequency when reducing speed.

Most systems have a plus/minus adjustment gain, and different types of brake systems can be installed on the trailer, making it simple to operate with enclosed trailers, campers, horse trailers, and boat trailers.

What does the “service trailer brake system” message mean?

The “Service Trailer Brake System” message informs you that the trailer brake system has disengaged due to wiring issues or some other problem. The brake system may be hampered if the trailer being towed doesn’t have enough power. In addition to the warning, there can be further symptoms. The problem may make it difficult to stop the trailer. When you brake, odd noises can also be heard.

Can you drive with the service trailer brake system message on?

You can drive a car with the service trailer brake warning message, but do not tow any loads until the issue is resolved. Ignoring the problem could lead to brake failure and unexpected collisions. So, while technically possible, it is not recommended or safe to drive with the trailer brake controller warning message.

what causes the service trailer brake system to come on?

Here are the most common causes why a service trailer brake system light comes on:

Blown Fuse

The most common and possible reason why your service trailer brake system message illuminates is due to a blown FUSE. A fuse controls the power of every electronic component in your car. In some scenarios, a blown fuse signals the possibility of a bigger issue, which is simple to identify if the problem reappears after replacing the fuse.

Defective Master Brake Cylinder/Sensor

Another possible cause of this message is either a defective master cylinder or sensor. A master cylinder and a few sensors are used in the brake system to make sure everything is working properly. This message may occasionally appear alongside others, signaling the presence of a more serious brake issue.

Faulty Brake Light Switch

The warning could be illuminated if the brake light switch malfunctions. The good news is that it is typically inexpensive to replace this component. In most car models, the brake light switch is positioned on the brake pedal, and changing it yourself is frequently relatively simple. But you must make sure that the switch is adjusted properly afterward.

Broken Trailer Brake Control Switch

In most car models with a trailer brake system, you often see a trailer brake controller behind the dashboard. This control switch for the trailer brakes may malfunction, necessitating replacement. Additionally, the connectors can be tainted or unclean.

Bad Wiring

Wiring problems could also be the reason why the service trailer brake system warning message comes on. The signals cannot be sent where they need to go when the wires get tattered or broken. The brake system warning appears on the dashboard as a result of this malfunction.

Differences between surge brakes and electric trailer brakes?

Surge brakes

This type of trailer brakes is a hydraulic self-contained braking system. Utilizing the weight of the trailer itself, the brakes are applied to reduce motion. With this type of non-electric trailer brake system, a hydraulic cylinder is compressed and pressure is transferred to the trailer brakes, slowing down the trailer when you apply the brakes to the car to slow it down.

Electric trailer brakes

In this type of trailer brakes, the vehicle is towed by electrical power. Electromagnetic brake drums are activated by an electric trailer brake system that electrically connects to the tow. The ability to willingly apply the brakes is then in the driver’s hands. Learn about brake master cylinder here!

https://studentlesson.com/everything-you-need-to-know-about-brake-master-cylinder/

How do you reset the service trailer brake system?

In order to reset the service trailer brake system, you’ll need a flathead screwdriver, hammer, piece of wood or rock, and assistant (optional). Here’s how to reset a service trailer brake system:

  • Find the adjustment nut on the trailer brakes’ backside. This is typically seen close to the axle.
  • Loosen the locknut holding the adjustment nut in place with the flathead screwdriver.
  • When the adjusting nut is snug against the backing plate, turn it clockwise. Avoid over-tightening.

What’s the cost of fixing the trailer brake system?

A service trailer brake system repair is estimated to cost about $300. This price includes all components, labor, and installation work. The type of trailer brake controller used and the mechanic performing the work can, however, affect the price of replacing the service trailer brake system. As a result, in any situation, make sure to make a budget and include the cost of repairing the trailer brake system in the budget.

How often should you service a trailer brake system?

Generally speaking, you should service your trailer brakes once a year or every 12,000 miles, whichever comes first. However, you might need to service the brakes more frequently if you use your trailer more often or over long distances. Keep an eye out for any indications that the brakes require maintenance and be mindful of how frequently you use your trailer.

Watch the video below to learn how to fix the Trailer Brake System of your vehicle:

 

FAQs

How do you reset trailer brakes?

Placing the pin back into the switch is all that is required to restart a breakaway system if your brakes are electric. Once the brakes are released, the trailer can roll freely.

Why does my trailer brake light keep coming on?

The brake light circuit appears to be constantly powered by what sounds like a fault in the wiring of your car or trailer. We recommend first inspecting the connector on both the vehicle side and the trailer side, checking the pins for rust or buildup, and then only cleaning if necessary.

How do you check trailer brakes?

To do this test, all that is necessary is to set the compass close to the brakes, supply electric current to them via the controller, and observe whether or not the compass moves. If the compass isn’t moving, the magnets aren’t receiving current, then your controller or wiring may be malfunctioning.

Is there a fuse for trailer brake lights?

If the turn signals were the issue, then simply check for and replace the trailer RT or LT fuse as required. Since that they use the same fuse, this will also solve the problems with the brake lights.

Where is the brake fuse located?

The power distribution center, which is either located behind the hood or under the dashboard, is where you’ll find the brake light system fuse, as well as all other fuses. The power distribution center, you’ve never heard of it? It is simply a fuse box’s technical name.

Can I drive with a brake system warning light?

Any fault with the brake system must be considered a serious safety concern, and your vehicle shouldn’t be driven until the issue has been fixed by a professional.

How do you service a brake system?

  • Maintain the proper levels of brake fluid by checking it frequently.
  • Examine the brake lines.
  • Change the brake fluid.
  • Examine the brake pads on your car, and if necessary, replace or upgrade them.

That it for this article, where I explained what a service trailer brake system is, its warning message, reasons why its light comes on, and how to reset it. I hope you learn a lot from the article. If you do, kindly share it with others. Thanks for reading; see you around!

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