How To Reset Service Trailer Brake System With This Easy DIY

Trailer Brake System is crucial specially for trucks with heavy trailers. These system may malfunction and need to reset for optimal work. So, How to reset Service Trailer Brake System? To do that, you need find the adjusting nut of the trailer brakes (close to the axle). Take a flat screwdriver to unbolt the locknut and then twist the adjusting nut clockwise.

To slow down the motion of a trailer, the trailer brake is the most important component indeed. When it can’t access or has some internal issue, you’ll immediately see the message on the dashboard ‘Service Trailer Brake System’. 

This message will irritate you by popping up every time your switch on the truck. Resting the fault code will help you get rid of this message. 

Here’s How To Reset Service Trailer Brake System!

No matter if it’s about Silverado, Chevy, or GMC Service Trailer Brake System, the message is easy to reset if you work with the parts. Without wasting time, I’ll share the steps below. 

Reset Service Trailer Brake System Infographic

Step 1: Gather the Parts Needed

You’ll need a two tools in order to start the reset procedure.

  • Flat Head Screwdriver 
  • Truck Jack 

Step 2: Jack The Rear End of Truck

Take the jack lifter and place it on the rear side of the truck. You can skip this step if you are comfortable working by bending your neck. 

Step 3: Find The Adjusting Nut Of The Trailer Brakes.

Grab the user manual of your specific truck model to understand the location of the trailer brake. Then, go to the backside of your truck and take out the wheel to reach the part (its usually the drive side, consult user manual for exact location). This plays a huge role in the Service Trailer Brake System reset.

Once the wheel is removed you need to locate the wheel adjuster. In most of the cases you will find it attached to the brake. Once located you need to attached this part to the brake shoe.

Step 4: Unbolt The locknut Using A Flat Screwdriver.

Take the flat screwdriver and gently use pressure to twist the locknut that holds the adjusting nut. In this step, you can use penetrating oil to moisten the nut if it looks rusty or cleans it using a cloth.

Step 5: Twist The Adjusting Nut Clockwise For Reset.

After locknut is remove use the screw driver to rotate the adjusting nut clockwise until it set firmly with the back plate and cannot be rotate with little twisting force. Care needed not to rotate the adjusting nut too much. 

Step 6: Attach Every Part Back To Their Places.

Insert the locknut inside the adjusting nut using the same screwdriver. Then, attach the wheel back to its place. Done!

Frequently Asked Questions

1. What does service trailer brake system mean?

It’s basically a fault code that pops on the truck dashboard (on those models that contain ITBC aka Integrated Trailer Brake Controller). This literally means a big issue with the trailer brake module or wiring.

2. How do you test a trailer brake connection?

To do that, you have to locate the brake magnet wire and use the negative lead of the multimeter on any of the wire of the system.

Next, put the positive lead of the multimeter into the battery. Read the multimeter to see any info about amperage shifting. If you see, then it means internal short. 

Wrapping Up

Now, seeing the message ‘Service Trailer Brake’ won’t terrify you. In case, the simple reset doesn’t fix the issue you are facing and shows the same message, I would suggest you change the trailer brake module.

Plus, replace the fuses and repair the wiring areas as these can fix the trouble. Hope this guide about how to reset Service Trailer Brake System is informative and descriptive to you to follow the steps. Catch You In Next Guide!

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William Baldwin

This Is William Baldwin, The Founder & Managing Editor of this website. Me and my team share automotive tips, tricks, and news

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Talha Atta

Talha Atta, a Mechanical Engineer and experienced technical content writer and editor at with a passion for the automotive industry.