Are you chasing down bizarre electrical issues in your GMC Sierra Denali? One minute the radio works, the next it’s dead? Are your power windows or door locks acting on their own? Before you spend a fortune on diagnostic fees, the culprit is often a failing Body Control Module (BCM). This VIN-programmed BCM, a direct replacement for part numbers like 15263363 and 25844480, is the definitive solution to restore full functionality and peace of mind to your truck.
From the Diagnostic Bay: The Case of the Haunted Sierra
I had a 2008 Sierra Denali roll into my shop last month with a laundry list of complaints that sounded like the truck was possessed. The dome lights would flicker, the security light would stay on randomly, and the HVAC blower was completely unresponsive. The owner had already replaced the battery and checked the main fuses. After connecting my scanner, I saw a handful of communication codes but the smoking gun was DTC B1001 (Option Configuration Error). This almost always points to an internal BCM failure. We swapped in a VIN-programmed module, and in less than 10 minutes, every single issue was resolved. It’s a common failure point I’ve seen on hundreds of these GM trucks, and this part is the fastest, most reliable fix.
Is Your Sierra Denali Showing These Electrical Gremlins?
A failing BCM doesn’t always cause a check engine light, but it creates a host of frustrating problems. If you’re experiencing any of the following, it’s time to inspect your module:
- ✔ Intermittent or completely dead HVAC controls and blower fan.
- ✔ Power windows, door locks, or mirrors that work sporadically or not at all.
- ✔ An airbag warning light on the dash, often with DTC B1001.
- ✔ Security system malfunctions, including no-start or stalling conditions.
- ✔ Headlights, taillights, or interior lights flickering or staying on.
- ✔ Communication errors with other modules on the vehicle’s network.
A 5-Minute Guide to Restoring Your Truck’s Electronics
One of the best features of this module is its simple, DIY-friendly installation. Because we program it to your vehicle’s VIN before shipping, you can skip the expensive trip to the dealership for coding. You can have your Sierra Denali Body Control Module swapped out in minutes.
- Safety First: Always disconnect the negative terminal from your truck’s battery before working on any electronics.
- Locate the BCM: On most GM trucks of this era, the BCM is located under the driver’s side of the dashboard, near the steering column. It’s a black box with several large multi-pin connectors.
- Swap the Module: Carefully unplug the electrical connectors from the old BCM. Unclip or unbolt the old module from its bracket and set it aside. Mount the new module in its place.
- Reconnect and Test: Firmly plug the connectors into your new BCM. Reconnect the negative battery terminal. Start the vehicle and test all functions—lights, locks, windows, radio, and HVAC—to confirm the repair.
Post-Installation Note: In some cases, if the airbag light was on, it may remain on after installation. This requires a professional scan tool to perform the ‘Setup SDM Primary Key in BCM’ function to sync the systems. A brake pedal position relearn may also be needed on certain models.
Verified Fitment for Your GM Truck or SUV
This module is a direct replacement for a wide range of General Motors vehicles. While this page focuses on the Sierra Denali Body Control Module, it is also compatible with the following models. Always verify your original part number for a perfect match. This module interchanges with: 25835966, 15263363, 15263497, 15878753, 15284816, 15943678, 15926094, 15940214, 25790508, 25790509, 25823558, 25823559, 25835965, 25844479, 25971916, 25971917, 15901388, 20939137, 20939138, 22860591.
- Cadillac: Escalade, Escalade ESV, Escalade EXT (2007-2013)
- Chevrolet: Avalanche 1500, Silverado 1500/2500/3500, Suburban 1500/2500, Tahoe (2007-2013)
- GMC: Sierra 1500/2500/3500, Sierra Denali, Yukon, Yukon XL (2007-2013)
Frequently Asked Questions
Do I need to program this BCM at the dealership?
No. We pre-program the module to your vehicle’s VIN before it ships. It arrives ready for a plug-and-play installation, saving you time and money.
What if my airbag light stays on after I install it?
This is a normal possibility. You will need a bi-directional scan tool to perform a ‘Setup SDM Primary Key in BCM’ procedure. This syncs the new BCM with the airbag system and is not a sign of a defective part.
Is there a core charge for my old part?
No, there is no core charge. You can keep or discard your old module without the hassle of sending it back.
Where is the BCM located on my 2009 Sierra Denali?
The BCM is typically found under the driver’s side dashboard, to the left of the steering column. It is a black plastic module with multiple large wiring harnesses connected to it.
Will this fix my intermittent HVAC blower motor?
Yes, a non-functional or erratic HVAC blower is one of the most common symptoms of a failing Sierra Denali Body Control Module. This part is designed to correct that issue.