End Frustrating Electrical Problems in Your GM Truck
If you’re dealing with a cascade of bizarre electrical issues in your GMC Sierra, Chevrolet Silverado, or other GM truck—from flickering lights and a dead HVAC system to mysterious warning lights—the Body Control Module (BCM) is the most likely culprit. As the central command for your vehicle’s body electronics, a failing BCM can make your reliable truck feel unpredictable. This replacement Body Control Module, part number 20939137, is the definitive solution. Through our professional cloning service, we transfer the exact configuration from your original module to this replacement, ensuring a seamless, plug-and-play installation without a costly trip to the dealership.
Case Study: A Tricky Diagnosis
A customer brought in a 2011 Silverado 2500 with a confusing set of symptoms: the radio would cut out, the driver-side power window worked intermittently, and the airbag light was on with a DTC B1001. They had already replaced the window switch and checked fuses with no luck. In my diagnostic bay, I’ve seen this exact combination dozens of times. Instead of chasing individual components, we went straight to the BCM. A failing BCM can corrupt communication between different systems, creating phantom problems. After installing one of our cloned BCMs, every single issue was resolved instantly. The key was understanding that the BCM was the single point of failure for all these unrelated-looking symptoms.
Is Your GM Truck Showing These Electrical Faults?
A faulty BCM can manifest in numerous ways. If you’re experiencing any of the following, it’s a strong indicator that your Body Control Module needs attention:
- ✔ Intermittent or non-functional HVAC controls, including the blower motor or A/C.
- ✔ An active airbag warning light, often accompanied by Diagnostic Trouble Code (DTC) B1001.
- ✔ Power accessories failing, such as power windows, door locks, or interior/exterior lights behaving erratically.
- ✔ Security system malfunctions, causing no-start conditions, stalling, or misfires.
- ✔ A variety of communication or body-related DTCs stored in the vehicle’s memory.
A Straightforward Guide to Installation
Our cloning service makes the physical replacement simple for any DIYer or professional technician. The entire process typically takes less than 15 minutes.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before working on electrical components.
- Locate the BCM: On most compatible GM trucks and SUVs, the BCM is located under the driver’s side dashboard, near the steering column. It’s typically a black plastic 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, unbolt or unclip the module from its mounting bracket.
- Install the New Module: Seat the cloned BCM into the mounting bracket and securely plug in all the electrical connectors. You should hear a click as they lock into place.
- Reconnect and Test: Reconnect the negative battery terminal. Start the vehicle and test all functions: lights, windows, locks, wipers, and HVAC to confirm the repair.
- Post-Installation Checks: In some cases, an ‘Airbag System Sync’ (Setup SDM Primary Key) or a ‘Brake Pedal Position Relearn’ may be needed using a professional scan tool if related warning lights appear. This is not always required but is a known possibility with these systems.
Verified Vehicle Compatibility
This module is a direct-fit replacement for a wide range of General Motors trucks and SUVs. It is interchangeable with part numbers 25835966, 15943678, 20939137, 22860591, and others. Please verify your part number or contact us to ensure compatibility for your specific vehicle, which includes models such as:
ESCALADE & ESV & EXT 07-11
SIERRA 1500 PICKUP 07-11
SIERRA 2500 PICKUP 07-13
SIERRA 3500 PICKUP 07-13
SIERRA DENALI (1500/2500/3500) 07-13
SILVERADO 1500 PICKUP 07-11
SILVERADO 2500 PICKUP 07-13
SILVERADO 3500 PICKUP 07-13
SUBURBAN 1500/2500 07-11
TAHOE 07-11
YUKON & YUKON XL 1500/2500 07-11
Frequently Asked Questions
What is a BCM cloning service?
Our cloning service is a process where we transfer all the critical vehicle-specific data—including VIN, mileage, and optional equipment configuration—from your original BCM to the replacement unit. This makes the new module a perfect electronic match for your truck, eliminating the need for expensive dealership programming.
Will I need to visit a dealer after installing this part?
No. Because the module arrives fully programmed with your vehicle’s data, it is a true plug-and-play solution. You will not need any further programming from a dealership, saving you time and money.
My airbag light is on after installation. What should I do?
If the airbag light persists, it means the new BCM needs to be synchronized with the vehicle’s Sensing and Diagnostic Module (SDM). This requires a professional scan tool to perform the ‘Setup SDM Primary Key in BCM’ procedure. This is a quick process for any well-equipped repair shop.
Where is the BCM located on my 2013 Sierra 2500 Pickup?
The BCM is typically found under the driver-side dashboard, to the left of the steering column. It is a black module with multiple wiring harnesses connected to it.
Do I need to send my old BCM back as a core?
Our cloning service requires your original module to transfer the data. Once the service is complete, we always return your original module to you along with the newly programmed replacement. There is no core charge or need to keep your old part.
What part numbers is this compatible with?
This module is a direct replacement for numerous part numbers, including 20939137, 25844480, 25835966, 15943678, 22860591, and many more. Please check the full list in our description or contact us to confirm your specific part number.