Restore Your Truck’s Electrical System
Are you battling strange and frustrating electrical problems in your GM truck or SUV? Flickering lights, unresponsive power windows, a dead HVAC system, or random warning lights are all classic signs of a failing Body Control Module (BCM). The BCM acts as the central command center for your vehicle’s body electronics, and when it malfunctions, it can cause a cascade of issues. This genuine GM Body Control Module, part number 25844480, is the definitive solution, arriving pre-programmed to your vehicle’s specific VIN for a true plug-and-play repair.
From the Diagnostic Bay
We had a 2011 Silverado in the shop with a ghost in the machine. The owner had spent hundreds chasing what he thought was a bad ground or a faulty HVAC control head because his air conditioning would cut out randomly. After hours of testing wires, we finally scanned the BCM and found multiple communication fault codes. A new, programmed BCM fixed not only the A/C but also an intermittent door lock issue he hadn’t even mentioned. Don’t waste time and money on guesswork; a faulty BCM is often the single root cause of multiple electrical gremlins.
Common Symptoms of a Failing BCM
- ✔ Power windows, door locks, or mirrors working intermittently or not at all.
- ✔ Interior or exterior lights staying on, flickering, or failing to activate.
- ✔ HVAC system malfunctions, such as the blower motor not working or temperature controls being unresponsive.
- ✔ Vehicle security system acting erratically or preventing the engine from starting.
- ✔ An active airbag warning light, often with Diagnostic Trouble Code (DTC) B1001.
- ✔ Unexplained battery drain while the vehicle is parked.
The Plug-and-Play Solution for Your 2013 Sierra Denali BCM
Forget expensive trips to the dealership for programming. We handle the complex part for you. Simply provide your vehicle’s VIN during checkout, and our technicians will flash this module with the latest GM software specific to your truck. This ensures that all factory-installed options work correctly right out of the box. This process restores communication between all related electronic systems, resolving common DTCs and restoring full functionality without any additional setup. This module is a direct replacement for a wide range of part numbers, including 25790508, 25835966, 15943678, 20939137, and 22860591, among others.
Installation and Post-Install Notes
Physical installation is straightforward for most DIY mechanics. The BCM is typically located under the driver’s side dashboard, near the steering column, and can be swapped in minutes. However, please be aware of a few potential post-installation procedures:
- Airbag System Sync: If the airbag warning light is illuminated after installation, a professional scan tool is required to perform the ‘Setup SDM Primary Key in BCM’ procedure. This 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 correct brake light and traction control operation.
There is no core charge for this part, so you can keep your old module without the hassle of returning it.
Frequently Asked Questions
What does a Body Control Module do on my Sierra?
The BCM is a computer that manages and controls many of your truck’s non-engine related electronic functions, including the power windows, door locks, interior/exterior lighting, security system, wipers, and HVAC climate controls.
Is this part ready to install when I receive it?
Yes! This BCM comes fully pre-programmed to your vehicle’s VIN. This makes the installation plug-and-play, with no need for an expensive trip to the dealership for programming.
Where is the BCM located on a 2013 GMC Sierra?
The Body Control Module is typically found under the driver’s side dashboard, to the left of the steering column. It is a black box with multiple large electrical connectors.
Why is my airbag light on after installing the new BCM?
This is a common security measure. The new BCM needs to be electronically ‘introduced’ to the airbag’s Sensing and Diagnostic Module (SDM). This requires a professional scan tool to perform the ‘Setup SDM Primary Key in BCM’ function to clear the light.
Do I need to return my old BCM?
No. We do not require you to return your original part. There is no core charge associated with this purchase, saving you time and money.
Will this BCM fix my intermittent wipers and radio issues?
Yes, a failing BCM is a very common cause of erratic behavior in wipers, radios, and other interior electronics. Replacing it with this programmed unit is the correct repair for those symptoms.