Tired of Unpredictable Electronics in Your GM Truck?
If you’re dealing with a 2007-2011 Silverado 2500 that seems to have a mind of its own—with flickering lights, a dead instrument cluster, or a security system that randomly prevents it from starting—you’ve likely met the common point of failure: the Body Control Module (BCM). As the central hub for your truck’s body electronics, when the BCM fails, it creates a cascade of frustrating and seemingly unrelated problems. This isn’t just an annoyance; it’s a reliability issue that can leave you stranded.
This replacement Body Control Module, part number 20939138, is the definitive solution. What makes our offering different is our expert Cloning Service. We transfer the critical data from your original BCM directly to this replacement unit. The result? A true plug-and-play module that requires absolutely no expensive trip to the dealership for programming. It will behave exactly as your original did, but without the faults.
Case Study: The Misleading Ground Fault
A customer brought in a 2009 Sierra 2500 with a classic BCM failure story: wipers wouldn’t turn off, and the radio would cut out intermittently. He had already replaced the battery and checked the main alternator wire, assuming it was a power supply issue. In my shop, I’ve seen this dozens of times. While poor grounds under the driver’s side A-pillar are a known issue on these GMT900 platforms and can damage the BCM over time, the module itself was the final point of failure. After confirming the grounds were now clean and secure, we installed one of our cloned BCMs. All the bizarre electrical issues vanished instantly. The key takeaway: always check your grounds during the BCM replacement to prevent a repeat failure.
Is Your Silverado Showing These Symptoms?
A failing BCM can manifest in numerous ways. If your truck is experiencing any of the following, a faulty BCM is the most likely cause:
- ✔ The security or anti-theft light stays on, causing a no-start condition.
- ✔ Power windows, door locks, or interior dome lights work intermittently or not at all.
- ✔ The HVAC system is unresponsive, or the blower motor is stuck on or off.
- ✔ Your scan tool shows communication error codes (U-codes) or specific BCM codes like B1001 (SDM configuration error).
- ✔ Headlights, taillights, or turn signals behave erratically.
- ✔ The radio or infotainment system randomly shuts down.
A Straightforward Guide to BCM Installation
One of the best parts of this repair is its simplicity. You don’t need a vehicle lift or complex tools. The entire swap can be done in your driveway in minutes.
- Safety First: Always disconnect the negative terminal from your truck’s battery before working on any electronic components.
- Locate the BCM: On most GM trucks of this era, the BCM is located under the driver’s side of the dashboard, to the left of the steering column. You may need to remove a lower dash panel for access.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old BCM. They have locking tabs that need to be depressed. Once disconnected, unclip the module from its mounting bracket.
- Install the New Module: Snap the cloned BCM into the mounting bracket and firmly reconnect all electrical harnesses. Ensure each connector clicks into place.
- Reconnect and Test: Reconnect the negative battery terminal. Turn the key to the ‘On’ position and test all functions: lights, wipers, locks, windows, and HVAC to confirm the repair was successful.
Important Post-Installation Steps
Our cloning service makes this a 99% plug-and-play process. However, due to the complex integration of safety systems, some vehicles may require an additional step:
- Airbag System Sync: If your airbag warning light is illuminated after installation (often with DTC B1001), a procedure called “Setup SDM Primary Key in BCM” must be performed. This requires a professional-grade scan tool and syncs the new BCM with the airbag system.
- Brake Pedal Position Relearn: On some models, a brake pedal position sensor relearn may be needed to ensure proper brake light and traction control operation. This is also done with a capable scan tool.
Guaranteed Fitment for Your GM Truck or SUV
This Body Control Module is a direct replacement for part number 20939138 and other interchangeable numbers. It is verified to fit the following vehicles:
CHEVROLET SILVERADO 1500 PICKUP 2007-2011
CHEVROLET SILVERADO 2500 PICKUP 2007-2011
CHEVROLET SILVERADO 3500 PICKUP 2007-2011
CHEVROLET SUBURBAN 1500/2500 2007-2011
CHEVROLET TAHOE 2007-2011
GMC SIERRA 1500 PICKUP 2007-2011
GMC SIERRA 2500 PICKUP 2007-2011
GMC SIERRA 3500 PICKUP 2007-2011
GMC YUKON & YUKON XL 2007-2011
CADILLAC ESCALADE, ESV, EXT 2007-2011
Note: Please verify your original part number or consult the detailed fitment list for specific model year options.
Frequently Asked Questions
What exactly is a “Cloning Service”?
Cloning is a process where we transfer the complete software, including your vehicle’s VIN, mileage, and key programming, from your original BCM to the replacement unit. This makes the new module an identical twin to your old one, ensuring seamless integration without any need for dealer programming.
Do I need to send my original BCM to you?
Yes. For the cloning service to work, you must send us your original module after placing your order. We will perform the service and ship both your original and the ready-to-install replacement back to you promptly.
Will this fix my airbag light for good?
This BCM will fix the airbag light if the BCM itself is the cause of the fault (like a B1001 code). However, after installation, you may need to perform the “SDM Primary Key Setup” with a scan tool to sync the modules and clear the light, as noted in the installation section.
Is this a difficult part for a DIYer to replace?
The physical replacement is very easy and typically takes less than 15 minutes with basic tools. It’s located in an accessible spot under the dashboard. The only potential complication is the need for a scan tool for post-installation procedures on some vehicles.
Is there a core charge for this part?
No, there is no core charge. We require your original module to perform the cloning service, and we always return it to you along with the newly programmed replacement unit.