Regain Complete Towing Control and Safety
Seeing the “Service Trailer Brake System” warning on your dash is more than an annoyance—it’s a critical safety alert that puts you, your cargo, and others at risk. When you’re hauling a heavy load with your Sierra or Silverado, you need absolute confidence that your trailer brakes will respond instantly. This VIN-programmed 20964299 Trailer Brake Control Module is the definitive solution to restore that safety and peace of mind, getting you back on the road without the worry.
Common Symptoms & Your Solution
A failing TBCM can manifest in several ways, often leaving you questioning your truck’s reliability. If you’re experiencing any of the following, this module is the component you need to get the job done right:
- “Service Trailer Brake System” message on the Driver Information Center (DIC)
- “Check Trailer Wiring” message, even with known good wiring
- Intermittent or complete loss of trailer brake function
- The manual trailer brake slider/switch is unresponsive
- Diagnostic Trouble Codes (DTCs) such as C1512, U0121, or U0415
Don’t waste time and money chasing wiring issues or paying for expensive dealership diagnostics. This module is the heart of your towing brake system, and replacing it with our pre-programmed unit is the most efficient and reliable repair.
Features & Tangible Benefits
- ✔ Programmed to Your VIN: We flash the module with the latest GM software specific to your truck. This means it’s a true plug-and-play part—no expensive trip to the dealer for programming is required.
- ✔ Restores Full Functionality: Regain precise, reliable control over your trailer’s brakes, ensuring safe and predictable stops every time you tow.
- ✔ Direct-Fit Replacement: Engineered to match the original factory part (20964299, 20850923) for a perfect fit and seamless integration with your truck’s systems.
- ✔ Clears Annoying Dash Warnings: Installing this module will extinguish the persistent “Service Trailer Brake System” message, cleaning up your dashboard and your worries.
- ✔ Built for Durability: Constructed to withstand the harsh environment under your truck frame, providing long-lasting performance for years of heavy-duty use.
- ✔ Purchase with Confidence: This unit is backed by our one-year replacement warranty.
An Expert’s Note on Programming: Many people buy a used or new TBCM online, only to find it doesn’t work when they install it. That’s because these modules are VIN-locked to the vehicle. A blank module requires a trip to the dealership and a hefty programming fee. We eliminate that entire frustrating and costly step. By providing your VIN at checkout, you receive a 20964299 Trailer Brake Control Module that is 100% ready to install right out of the box. It’s the difference between a 30-minute driveway repair and a multi-day ordeal with the dealer.
Frequently Asked Questions
What is the process after I place my order?
After you complete your purchase, you must provide us with your vehicle’s 17-digit VIN. We cannot ship the module until we have this information, as we use it to program the unit specifically for your truck’s configuration and options.
Is this part difficult to install?
For most 2013-2014 GM HD trucks, the module is located on the driver’s side frame rail, near the rear axle. Installation is straightforward for someone with basic mechanical skills. It involves disconnecting the battery, unplugging the electrical connectors, and removing a few bolts. No special tools are required.
Will this definitely fix my “Service Trailer Brake System” message?
In the vast majority of cases for these specific vehicles, a faulty TBCM is the root cause of that warning message and related braking issues. While we can’t guarantee it will fix every vehicle without a proper diagnosis, it is the most common and probable solution to the problem.
Is this compatible with my factory in-dash trailer brake controller?
Yes. This module is the computer or ‘brain’ that receives signals from your in-dash controller (the part with the slider and buttons) and sends the correct power to the trailer’s brakes. They work together as a system.
What happens if I forget to send my VIN?
Your order will be placed on hold. Our customer service team will reach out to you to request the VIN. To ensure the fastest possible shipping, please provide your VIN during checkout or immediately after placing your order.