Restore Full Control Over Your HUMMER’s Electronics
Are you battling frustrating electrical gremlins in your 2008-2009 HUMMER H2? Intermittent power windows, flickering dash lights, a security system that acts up, or even a vehicle that refuses to start can all point to a single culprit: a failing Body Control Module (BCM). As the central command for your vehicle’s body electronics, a faulty BCM can create a cascade of confusing and unpredictable problems. This isn’t just an annoyance; it’s a matter of reliability and safety.
This is a direct-fit replacement BCM, part number 25847588, that arrives at your door fully programmed to your HUMMER’s specific Vehicle Identification Number (VIN). We handle the complex software flashing process for you, loading the latest GM updates. This means you can bypass the expensive and time-consuming trip to the dealership for programming. Simply provide your VIN after purchase, and we’ll prepare a module that’s ready for installation right out of the box.
A Technician’s Notebook
I remember a 2008 H2 that came into the shop with a classic case of BCM failure. The owner was fed up. One day the radio wouldn’t turn off, the next the power locks were dead, and the final straw was an intermittent no-crank condition. A scan showed multiple U-codes (communication loss) with various modules. After confirming power and ground to the BCM were solid, we knew the module itself was the issue. Swapping in a pre-programmed unit like this one had all systems back online in under an hour. It’s a common failure point, but thankfully, a straightforward fix with the right part.
Common Signs of a Failing BCM
If your vehicle is experiencing any of the following, a failing 2008-2009 HUMMER H2 BCM could be the cause. A proper diagnosis is key, but these are tell-tale symptoms I’ve seen countless times.
- ✔ Power windows, door locks, or mirrors operating erratically or not at all.
- ✔ Interior or exterior lights flickering, staying on, or not working.
- ✔ The security system light flashing, preventing the engine from starting (Passlock issues).
- ✔ The horn sounding randomly or not working when pressed.
- ✔ Multiple, unrelated warning lights on the instrument cluster.
- ✔ Diagnostic trouble codes (DTCs) related to communication errors, such as U0140, U0155, or U0164.
Your H2 BCM Installation Guide
Installing your new BCM is a manageable job for a confident DIYer. For the 2008-2009 HUMMER H2, the BCM is typically located on the driver’s side, attached to the firewall. Always consult a service manual for your specific vehicle configuration.
- Safety First: Disconnect the negative terminal from your vehicle’s battery and wait a few minutes to ensure all systems are powered down.
- Locate the BCM: On the H2, find the BCM mounted to the firewall on the left-hand (driver’s) side of the cabin, often behind the lower dash panel.
- Disconnect and Remove: Carefully unplug the electrical connectors. They have locking tabs that need to be released. Once disconnected, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed BCM into place. Reconnect all electrical connectors, ensuring they click securely into position.
- Reconnect Power: Reattach the negative battery terminal.
- Perform Relearns: Start the vehicle and check all functions. As noted below, you may need to perform a relearn procedure for the airbag system or brake pedal position sensor if related warning lights are present.
Important Post-Installation Steps
While this BCM is programmed for your vehicle, some systems may need to be re-synchronized after installation:
- Airbag System Sync: If the airbag light is on after installation, a scan tool procedure called “Setup SDM Primary Key in BCM” is required to sync the modules.
- Brake Pedal Position Relearn: On some models, a brake pedal position sensor relearn may be needed to ensure correct brake light and stability control function.
Disclaimer: Vehicle systems vary. Always refer to a factory service manual or a certified mechanic for detailed procedures.
Will This Fit My Vehicle?
This module is a guaranteed fit for the 2008-2009 HUMMER H2. It also serves as a direct replacement for a wide range of other GM vehicles that use any of the following part numbers: 10382479, 15093910, 15276271, 15299986, 15819552, 15828601, 15837419, 15872388, 15872421, 15880684, 15921352, 15921353, 15948438, 15948439, 20815898, 20839063, 20864767, 20864768, 20921435, 20921436, 20935349, 22860591, 25826124, 25826125, 25847588, 25847589, 25892622, 25910474, 25934762, 25934763, and 95151084. Please verify your original part number to ensure compatibility.
Do I need to do any programming myself?
Do I need to do any programming myself?
No. We program the module to your vehicle’s VIN before we ship it. It arrives ready to be installed, saving you a trip to the dealership.
Do I have to return my old BCM?
No, there is no core charge for this part. You can keep your old module.
What tools are needed for the post-installation procedures?
The Airbag System Sync and Brake Pedal Position Relearn procedures require a professional-grade bidirectional scan tool. Many local repair shops can perform these services if needed.
How do I provide my VIN?
After you complete your purchase, you will need to send us your 17-digit VIN. We cannot program and ship your BCM without it.