Restore Full Control Over Your Truck’s Electronics
Are you tired of dealing with baffling electrical issues in your Chevy or GMC truck? One moment the power windows work, the next they don’t. The HVAC blower motor has a mind of its own, and strange warning lights keep appearing on your dash. These aren’t just minor annoyances; they’re classic signs of a failing Body Control Module (BCM), the central hub of your vehicle’s body electronics. This replacement BCM, part number 20939137, is the definitive solution for your 2007-2011 Silverado 3500 BCM and other compatible GM vehicles.
Think of the BCM as your truck’s nervous system. It manages everything from the lights and locks to the security system and climate controls. When it starts to fail, it can cause a cascade of frustrating and unpredictable problems. Our unique cloning service makes this repair easier than ever. We transfer the exact data from your original module to this replacement unit, ensuring it arrives at your door fully programmed and ready for a simple, plug-and-play installation. No expensive trips to the dealership for programming are required.
Case Study: The Ghost in the Machine
A customer brought in his ’09 Sierra 2500 with a laundry list of complaints: intermittent no-start, radio cutting out, and an airbag light that wouldn’t go away (DTC B1001). He’d already replaced the battery and alternator, thinking it was a power supply problem. After a quick scan, I suspected the BCM. In my 20+ years, I’ve seen hundreds of these GMT900 platform trucks where a failing BCM mimics a bad ground or battery. We performed our cloning service onto a new BCM. After a 5-minute install, every single issue was resolved. It’s a textbook example of how a single module failure can send you chasing expensive, incorrect diagnoses.
Is Your Silverado Showing These Electrical Gremlins?
- ✔ The security light is flashing, and the engine occasionally stalls or won’t start.
- ✔ Power windows, door locks, or interior/exterior lights work intermittently or not at all.
- ✔ Your HVAC controls are unresponsive, or the blower fan speed is erratic.
- ✔ An airbag warning light is illuminated, often with a DTC like B1001 stored in the system.
- ✔ The dashboard is lit up with multiple, seemingly unrelated warning lights.
- ✔ You’re experiencing strange communication errors between modules (U-codes).
A Straightforward Guide to Installation
- ✔ Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- ✔ Locate the BCM: On most Silverado and Sierra models, the BCM is located under the driver’s side of the dashboard, near the steering column. It’s a black box with several large electrical connectors.
- ✔ Remove the Old Module: Carefully unplug the electrical connectors. They have locking tabs that need to be depressed. Once unplugged, unclip or unbolt the module from its mounting bracket.
- ✔ Install the New Module: Connect the electrical harnesses to your new, cloned BCM. The plugs are keyed and will only fit in their correct positions. Secure the module back onto its bracket.
- ✔ Reconnect and Test: Reconnect the negative battery terminal. Start the vehicle and test all functions: lights, locks, windows, wipers, and HVAC to confirm the repair was successful.
- ✔ Post-Install Checks: If the airbag light remains on, a professional scan tool is needed to perform the ‘Setup SDM Primary Key in BCM’ function. Some models may also require a ‘Brake Pedal Position Relearn’.
Verified Vehicle Compatibility
This module is a direct replacement for part number 20939137 and other interchangeable parts on a wide range of General Motors trucks and SUVs. While this page focuses on the 2007-2011 Silverado 3500 BCM, it also fits many other models. Please verify your part number or contact us with your VIN to ensure perfect fitment for vehicles like:
- Chevrolet Silverado 1500, 2500, 3500 (2007-2013)
- GMC Sierra 1500, 2500, 3500 & Denali (2007-2013)
- Chevrolet Avalanche, Suburban, Tahoe (2007-2013)
- GMC Yukon, Yukon XL (2007-2013)
- Cadillac Escalade, ESV, EXT (2007-2011)
This part is interchangeable with: 25835966, 15263363, 15878753, 15943678, 25790508, 25844480, 25971916, 15901388, 20939138, and 22860591 among others.
Frequently Asked Questions
How does the cloning service work?
You send us your original Body Control Module. We use specialized equipment to read the critical vehicle-specific data (including VIN, mileage, and key information) and transfer it directly to your new module. This makes the replacement 100% plug-and-play.
Do I need to get this programmed at the dealer?
No. Our cloning service completely eliminates the need for dealership programming, saving you time and money. It will be ready to install right out of the box.
Why is my airbag light still on after installation?
This is a common security feature in GM vehicles. If the airbag light is on, it means the new BCM needs to be synced with the airbag system’s SDM. This requires a ‘Setup SDM Primary Key in BCM’ procedure using a professional-grade scan tool.
What if my original module is completely dead or missing?
If your original module cannot be read (due to fire, water damage, or it’s missing), we can often program a replacement using your vehicle’s VIN. Please contact us first to discuss this option.
Do you keep my old part? What about a core charge?
There is no core charge. We always return your original module to you along with the newly programmed replacement unit.