Regain Complete Control and Safety While Towing
Seeing the ‘Service Trailer Brake System’ message on your dash is more than an annoyance—it’s a critical safety warning. It means the crucial link between your truck and your trailer’s brakes is compromised. This VIN-programmed Trailer Brake Control Module (TBCM) is the definitive solution to restore full functionality and give you back the peace of mind you need when hauling heavy loads. Designed as a direct replacement, this module arrives flashed with the latest GM software specific to your vehicle, eliminating the need for an expensive trip to the dealership for programming.
Common Symptoms & Your Direct-Fit Solution
If you’re experiencing any of the following issues, a failing TBCM is the most likely culprit. This module is engineered to resolve them permanently:
- Persistent “Service Trailer Brake System” warning on the instrument cluster
- Trailer brakes failing to engage or engaging erratically
- “Trailer Connected” or “Trailer Disconnected” messages flashing incorrectly
- Diagnostic Trouble Codes (DTCs) such as C1115, C1116, or C1124
By installing our expertly prepared 2013-2014 Sierra Silverado Trailer Brake Control Module, you’re not just replacing a part; you’re restoring your truck’s integrated towing system to factory-spec performance, ensuring predictable and reliable braking for whatever you’re pulling.
Features & Benefits
- ✔ VIN-Programmed for Your Truck: Arrives ready to install right out of the box. We flash it with the latest GM updates using your specific VIN, ensuring perfect communication with your truck’s other systems.
- ✔ No Dealer Visit Required: Save hundreds of dollars and valuable time by avoiding dealership programming fees. This is a true plug-and-play fix.
- ✔ Restores Full Functionality: Eliminates warning messages and restores complete control over your trailer’s brakes, including the manual override slider.
- ✔ Direct OE Fit and Function: Engineered to be a direct replacement for part numbers 20964299 and 20850923, guaranteeing a perfect fit and seamless integration.
- ✔ Built for Durability: Designed to withstand the harsh under-vehicle environment where it’s mounted, providing a long-lasting solution to a common problem.
- ✔ This unit is backed by our one-year replacement warranty.
An Expert’s Insight on TBCM Failure
“Over my 20 years under the hood, I’ve seen dozens of these modules fail. The key thing to understand is its location. On these GM HD trucks, the TBCM is mounted on the driver-side frame rail, right in the line of fire for everything the road kicks up—water, mud, and especially corrosive road salt in winter climates. The original seals can degrade over time, allowing moisture to seep into the circuit board, causing corrosion and eventual failure. When you install a new 2013-2014 Sierra Silverado Trailer Brake Control Module, it’s a good practice to apply a light coat of dielectric grease to the connector pins to add an extra layer of protection against the elements.”
Frequently Asked Questions
What do I need to do after I place my order?
After you complete your purchase, you must send us your vehicle’s 17-digit VIN. We cannot ship your part until we have this information, as we use it to program the module specifically for your truck’s configuration.
Is this module difficult to install?
No, the installation is straightforward for anyone with basic mechanical skills. The module is typically located on the driver-side frame rail, near the rear axle. It’s held in place by a few bolts and has one electrical connector. Since our module is pre-programmed, it is a simple plug-and-play process with no special tools required.
Will this definitely fix my ‘Service Trailer Brake System’ message?
In the vast majority of cases, yes. A faulty TBCM is the most common cause of this specific warning message and the associated symptoms on 2013-2014 GM HD trucks. This 2013-2014 Sierra Silverado Trailer Brake Control Module is the correct and reliable fix for that issue.
Is this compatible with my Sierra Denali 3500?
Yes, this module fits a range of GM heavy-duty vehicles, including the 2013-2014 Sierra 2500/3500, Sierra Denali 2500/3500, Silverado 2500/3500, as well as the 2013 Suburban 2500 and Yukon XL 2500. It is a direct replacement for the towing control module on these models.
What is the difference between part numbers 20964299 and 20850923?
Both part numbers refer to the same component. 20964299 is often a newer, superseding part number for 20850923. Our module is a compatible replacement for both, and we program it with the most current software available for your vehicle.