Restore Critical Towing Safety and Clear Annoying Dash Warnings
Seeing the “SERVICE TRAILER BRAKE SYSTEM” message on your dash is more than an annoyance—it’s a critical safety alert that your truck’s ability to control a heavy trailer is compromised. Whether you’re hauling equipment to a job site or pulling a fifth-wheel for a weekend getaway, you need absolute confidence in your braking system. This Trailer Brake Control Module (TBCM) is the definitive solution, arriving pre-programmed specifically to your truck’s VIN for a seamless, plug-and-play installation.
Common Symptoms & Your Direct-Fit Solution
A failing TBCM can manifest in several ways, all of them compromising your control and safety. If you’re experiencing any of the following, this module is the component you need to restore proper function:
- Persistent “SERVICE TRAILER BRAKE SYSTEM” warning light.
- “TRAILER CONNECTED” and “TRAILER DISCONNECTED” messages cycling randomly, even with a trailer securely hitched.
- No output or weak response from the manual trailer brake controller slide.
- Diagnostic Trouble Codes (DTCs) related to the TBCM, such as C1512, C1522, or loss of communication faults.
Don’t waste time and money on a dealership visit for programming. We handle the critical software flashing for you. By providing your VIN at checkout, you receive a module that integrates perfectly with your truck’s systems right out of the box. This is the most efficient way to get your 2013-2014 Sierra 3500 Trailer Brake Control Module 20850923 working correctly again.
Features & Benefits
- ✔ Ready for Installation: This module is professionally programmed to your vehicle’s specific VIN, eliminating the need for expensive dealer tools or appointments.
- ✔ Latest GM Software: We flash each unit with the most current updates from General Motors, ensuring optimal performance, bug fixes, and maximum compatibility.
- ✔ Restored Safety & Control: Regain precise, reliable control over your trailer’s brakes for safer stops and confident handling of heavy loads.
- ✔ Eliminate Dash Clutter: Permanently clear the persistent and distracting trailer brake system warnings from your driver information center.
- ✔ Direct-Fit Replacement: Engineered to replace OEM part numbers 20850923 and 20964299, guaranteeing a perfect fit and connection on the LH rear frame of your truck.
- ✔ Total Peace of Mind: This unit is backed by our one-year replacement warranty.
Expert Insight: The Unseen Risk of a Faulty TBCM
As a technician, I’ve seen firsthand what happens when a TBCM fails at the wrong moment. Imagine descending a steep grade with a 12,000-pound trailer. You apply the brakes, expecting the trailer to help slow the entire rig. Instead, nothing happens. The full weight pushes your truck, causing brake fade and a terrifying loss of control. This isn’t just about a warning light; it’s about the fundamental physics of safe towing. A fully functional 2013-2014 Sierra 3500 Trailer Brake Control Module 20850923 isn’t a convenience—it’s a non-negotiable safety component that protects you, your investment, and everyone else on the road.
Frequently Asked Questions
Do I need to take this part to a dealer for programming?
No. The main benefit of our service is that we program the module to your specific vehicle’s VIN before we ship it. This means it’s ready for installation the moment it arrives, saving you time and the high cost of dealership programming.
Where is this module located on my truck?
For 2013-2014 Sierra and Silverado pickups, this module is typically located on the driver’s side frame rail, towards the rear of the vehicle. On the Suburban 2500 and Yukon XL 2500, it’s found on the driver’s side, in the middle of the frame. Always disconnect the battery before replacement.
What causes the “SERVICE TRAILER BRAKE SYSTEM” message?
This message is triggered when your truck’s main computer detects a fault within the trailer brake control system. The most common cause is the internal failure of the TBCM itself due to age, moisture intrusion, or electronic component failure. This pre-programmed 2013-2014 Sierra 3500 Trailer Brake Control Module 20850923 is the direct fix for this issue.
How do I provide you with my vehicle’s VIN?
After you complete your purchase, you will need to send us your 17-digit VIN. You can add it as a note to your order during checkout or reply to your order confirmation email. We cannot ship the part until we have this information to program it correctly.
Is this module compatible with part number 20964299?
Yes, this module is a fully compatible and direct replacement for part numbers 20850923 and 20964299, covering the same applications and offering identical functionality.