Restore Full Electrical Function to Your GM Truck or SUV
Are you battling frustrating electrical issues in your 2007-2011 GMC Sierra 1500? Flickering lights, unresponsive power windows, a malfunctioning security system, or a dead HVAC blower are all classic signs of a failing Body Control Module (BCM). The BCM is the central command center for your truck’s body electronics, and when it fails, it can cause a cascade of seemingly unrelated problems. This genuine OEM-quality Body Control Module, part number 20939138, is the definitive solution to restore your vehicle’s performance and reliability.
From the Diagnostic Bay
We had a 2010 Sierra 1500 come into the shop with the owner at his wit’s end. The radio would turn on and off by itself, the driver’s side power window worked intermittently, and the airbag light was on with a B1001 code. He’d already replaced the battery and checked fuses. After a quick scan, we confirmed communication errors with the BCM. Instead of a complex and expensive wiring chase, we installed a VIN-programmed module like this one. In under 10 minutes, plus a quick SDM key sync with our scanner, all the ghost-like electrical problems were gone. It’s a common failure, but thankfully, a straightforward fix with the right part.
Why Choose Our Pre-Programmed Sierra 1500 BCM?
This isn’t just a replacement part; it’s a complete, plug-and-play solution. We pre-program each module to your vehicle’s specific Vehicle Identification Number (VIN) before shipping. This critical step ensures that the BCM communicates flawlessly with your truck’s other electronic systems, like the Engine Control Module (ECM) and Supplemental Inflatable Restraint (SIR) system. You can skip the expensive trip to the dealership for programming—this module arrives ready for immediate installation, saving you time and money.
Common Symptoms of a Failing BCM
- ✔ Intermittent or non-working power windows, door locks, or interior/exterior lights.
- ✔ HVAC controls are unresponsive, or the blower motor works sporadically.
- ✔ The vehicle’s security system malfunctions, causing starting issues or false alarms.
- ✔ An illuminated airbag warning light, often with DTC B1001.
- ✔ Unexplained battery drain when the vehicle is off.
- ✔ Communication-related Diagnostic Trouble Codes (DTCs) stored in the system.
Installation and Post-Install Procedures
Installation is simple for the average DIY mechanic. The BCM is typically located under the driver’s side dashboard, near the steering column. In most cases, it’s a matter of disconnecting the negative battery terminal, unplugging the electrical connectors from the old module, removing it, and installing the new one. However, please be aware of potential post-installation steps:
- Airbag System Sync: If the airbag warning light is illuminated after installation, a ‘Setup SDM Primary Key in BCM’ procedure is required. This must be done with a professional-grade scan tool and syncs the new BCM with the airbag system.
- Brake Pedal Position Relearn: Some models may require a brake pedal position sensor relearn to ensure proper brake light and stability control operation.
This module is a direct replacement for multiple part numbers, including 25844480, 25835966, 20939137, and 22860591. Restore your truck’s electrical integrity and peace of mind with this reliable, pre-programmed Sierra 1500 BCM.
Frequently Asked Questions
What does a Body Control Module (BCM) do?
The BCM acts as the central computer for your vehicle’s body electronics. It controls non-engine related functions like power windows, door locks, lights, wipers, the security system, and the HVAC blower motor.
Is this BCM truly plug-and-play?
Yes, it is. We program the module to your vehicle’s VIN before it ships, so it’s ready for installation right out of the box. This eliminates the need for a costly visit to the dealership for programming.
My airbag light is on. Will this fix it?
If the airbag light is caused by a faulty BCM (like with code B1001), this module will resolve the root cause. However, after installation, you will need a professional scan tool to perform the ‘Setup SDM Primary Key in BCM’ procedure to sync the systems and turn off the light.
Do I need to return my old BCM?
No, there is no core charge for this part. You can keep your old module, which saves you the time and hassle of shipping it back.
Where is the BCM located on my 2008 Sierra 1500?
On most 2007-2013 GM trucks and SUVs, including the Sierra, the BCM is located under the driver’s side dashboard, typically to the left of the steering column.