If your 2007-2011 GMC Sierra 3500 is plagued by frustrating electrical problems—like flickering lights, a dead HVAC system, or power windows with a mind of their own—the Body Control Module (BCM) is the most likely culprit. As the central command for your truck’s body electronics, a failing BCM can create a cascade of issues that are often difficult to diagnose. This OEM-quality replacement BCM, part number 25823559, is the definitive solution to restore full functionality and reliability to your vehicle.
We take the guesswork and high dealership costs out of the repair. Each module is expertly programmed to your truck’s specific Vehicle Identification Number (VIN) before it ships. This ensures it communicates perfectly with your vehicle’s other systems right out of the box, eliminating the need for expensive programming appointments. Get your truck’s essential features working like new again.
Is Your Sierra Exhibiting These Glitches?
- ✔ The HVAC blower motor works intermittently or not at all, leaving you without heat or A/C.
- ✔ Your airbag warning light is illuminated on the dash, often with a DTC B1001 stored in the system.
- ✔ A host of electrical accessories are failing, such as power door locks, interior lights, or windshield wipers.
- ✔ The security system is malfunctioning, causing no-start conditions, stalling, or erroneous alerts.
- ✔ You’re chasing down confusing diagnostic trouble codes (DTCs) related to body systems and communication errors.
A Technician’s Notebook: The Ghost in the Machine
I once had a 2009 Sierra 2500 in the bay that was driving its owner crazy. The symptoms were all over the place: sometimes the radio would cut out, other times the dome lights wouldn’t turn off, and occasionally it would refuse to start. The customer had already replaced the battery and checked the alternator. After scanning, I found a slew of communication codes. The root cause wasn’t the BCM itself, but a corroded ground wire connected near the module’s mounting location under the dash. We replaced the BCM and repaired the ground connection, and the truck has been perfect ever since. It’s a powerful reminder: when you replace a Sierra 3500 Body Control Module, always inspect the ground points. A solid ground is critical for any electronic module to function correctly.
Your 5-Minute BCM Installation Guide
Getting your truck back to normal is a straightforward process that you can do in your own driveway. The BCM is located under the driver’s side dashboard, near the steering column.
- Safety First: Always disconnect the negative terminal from your truck’s battery before working on any electrical components.
- Locate the Module: Remove the lower dash panel beneath the steering wheel to access the BCM. It’s a black box with multiple large electrical connectors.
- Swap the Connectors: Carefully unclip and disconnect the wiring harnesses from the old BCM. They are color-coded and keyed, so they can only go back in one way.
- Install the New BCM: Mount your new, pre-programmed module in place and securely plug in all the connectors.
- Power Up & Test: Reconnect the battery terminal. Start the truck and test all functions—lights, windows, locks, wipers, and HVAC—to confirm the repair is complete.
Post-Installation Note: In some cases, particularly if the airbag light was on, a ‘Setup SDM Primary Key in BCM’ procedure may be needed using a professional scan tool. A Brake Pedal Position relearn might also be required. These are simple procedures for any competent mechanic if needed.
Verified Compatibility for Your GM Truck or SUV
This Sierra 3500 Body Control Module is a direct replacement for part number 25823559 and is interchangeable with a wide range of other part numbers, including 25844480, 25835966, 15940214, 20939137, and 22860591. It provides guaranteed fitment for many 2007-2013 GM vehicles, such as:
GMC Sierra 1500/2500/3500, Sierra Denali, Yukon, Yukon XL
Cadillac Escalade, Escalade ESV, Escalade EXT
With our VIN programming service and a one-year warranty, you can be confident you’re getting a reliable, long-term fix. There is no core charge, so you don’t have to worry about the hassle of sending your old part back.
Frequently Asked Questions
What does this Sierra 3500 Body Control Module actually do?
The BCM acts as the brain for your truck’s non-engine electronics. It controls features like your interior and exterior lights, power windows and locks, security system, windshield wipers, and the HVAC climate control system.
Is this module difficult to install myself?
Not at all. For most DIYers, this is a very simple job that takes less than 15 minutes. It’s located under the driver’s side dash and involves swapping a few electrical connectors. No special tools are required for the physical installation.
Will I have to go to the dealership for programming after installation?
No. We pre-program the module to your vehicle’s VIN before shipping. This means it’s ready for plug-and-play installation, saving you the time and expense of a dealership visit.
What if my airbag light stays on after I install the new BCM?
If the airbag light remains on, it simply means the new BCM needs to be synced with the airbag system’s SDM module. This requires a professional scan tool to perform the ‘Setup SDM Primary Key in BCM’ procedure, which is a quick task for any repair shop.
Do I need to send my old part back? Is there a core charge?
No, there is no core charge. You can keep or dispose of your old module without any extra fees or hassle.