Are you dealing with baffling electrical issues in your GMC Envoy XL or another compatible GM SUV? One moment the power windows work, the next they don’t. Maybe your interior lights have a mind of their own, or you’re seeing strange warning messages on the dash. These are classic signs of a failing Body Control Module (BCM), the central computer for your vehicle’s comfort and convenience features. Don’t let these electrical gremlins frustrate you any longer. This is a direct-fit, professionally programmed BCM that restores full functionality, shipped directly to you, ready for installation.
We take the guesswork and dealer-level expense out of the repair. Simply provide your vehicle’s VIN at checkout, and our technicians will program this module with the very latest GM software specific to your SUV. This ensures seamless integration and performance right out of the box, solving the root cause of those annoying electrical faults. This is the most efficient way to get your vehicle back to 100% without the high cost and scheduling headaches of a dealership visit.
Case Study: A Tricky Diagnosis
I remember a 2006 Trailblazer that came into my bay with a complaint of the radio and power windows randomly quitting. The customer had already replaced the battery and checked all the fuses. Diagnostics showed intermittent communication loss codes (U-codes) with several modules. On these GMT360 platform vehicles, the BCM is integrated into the under-hood fuse block, exposing it to moisture and thermal stress. After confirming power and grounds were good, we identified the BCM as the culprit. A replacement, pre-programmed module like this one had the truck fixed in under an hour, saving the customer hundreds compared to the dealership alternative.
Is Your SUV Showing These BCM Failure Signs?
- âś” Erratic or non-functional power windows, door locks, and mirrors.
- âś” Interior or exterior lights that stay on, flicker, or won’t turn on at all.
- âś” The security or anti-theft system preventing the engine from starting.
- âś” Inoperative radio, climate controls, or instrument cluster gauges.
- âś” False warning lights appearing on the dashboard.
- âś” Diagnostic trouble codes (DTCs) related to communication errors, such as U0140, U0155, or U0164.
- âś” A dead battery from parasitic draw caused by a faulty module.
Your Straightforward BCM Installation Guide
Replacing the BCM on these vehicles is a manageable job for a DIYer with basic tools. The BCM is part of the main fuse box assembly under the hood.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait a few minutes for the system to discharge completely.
- Locate the Module: Open the hood and find the main fuse box, typically located on the driver’s side of the engine bay. Remove the cover.
- Disconnect Connectors: Carefully unplug all the large electrical connectors attached to the fuse box/BCM assembly. Use a small flathead screwdriver to gently release the locking tabs if needed.
- Remove the Old Unit: Unbolt the fuse box assembly from its mounting points in the engine bay.
- Install the New BCM: Mount your new, pre-programmed BCM/fuse box assembly in place and secure the bolts.
- Reconnect Everything: Plug all electrical connectors back into their correct positions. They are keyed and will only fit one way. Reconnect the negative battery terminal.
- Perform Final Checks: Start the vehicle and test all functions—windows, locks, lights, radio, etc. Address any post-installation procedures as noted below if warning lights appear.
Important Post-Installation Information
While this module is programmed for your VIN, some vehicle systems may require a ‘handshake’ with the new BCM. Please be aware of the following potential procedures:
- Airbag System Sync: If the airbag warning light is illuminated after installation, a simple ‘Setup SDM Primary Key in BCM’ procedure is needed. This requires a professional-grade scan tool to sync the modules and will clear the light.
- Brake Pedal Position Relearn: On some models, a brake pedal position sensor recalibration may be required to ensure your brake lights and traction control system function correctly.
Disclaimer: Specific requirements can vary. We always recommend consulting a factory service manual or a qualified technician for guidance.
Verified Fitment For These GM SUVs
This Body Control Module is a guaranteed fit for the following vehicles, replacing part numbers 25802312, 8258023120, 15135466, and 15787809. Please match your vehicle and options below:
- 2005-2009 GMC Envoy (w/o security system)
- 2005-2006 GMC Envoy XL (w/o security system)
- 2005-2009 Chevrolet Trailblazer (w/o security system)
- 2005-2006 Chevrolet Trailblazer EXT (w/o security system)
- 2005-2007 Buick Rainier (w/o security system)
- 2005-2008 Isuzu Ascender (w/o security system for 05-07)
- 2006-2009 Saab 9-7X
Frequently Asked Questions
Do I really need to provide my VIN?
Yes, absolutely. Providing your VIN is the most critical step. We use it to load the precise factory software and calibrations for your specific vehicle’s options. This step is what makes the installation process so simple and effective, preventing compatibility issues.
What if my airbag light comes on after I install it?
This is not a defect. It simply means the new BCM needs to be electronically introduced to the airbag system’s computer (SDM). A repair shop or a technician with a bi-directional scan tool can perform the ‘Setup SDM Primary Key in BCM’ procedure in a few minutes to resolve this.
Is this a difficult part to install myself?
For most DIYers with basic mechanical skills, this is a very straightforward installation. The BCM is integrated with the under-hood fuse box, making it easy to access. No special tools are needed for the physical swap, but a scan tool may be required for post-install relearn procedures as noted.
My old part number isn’t 8258023120, but it is on your list. Will this work?
Yes. Manufacturers often update part numbers over time. This module is the correct service replacement for all part numbers listed, including 25802312, 15135466, and 15787809. As long as your vehicle is on the fitment list, this part will work correctly.
What does ‘No Core Charge’ mean?
It means you do not have to send your old, faulty BCM back to us. You can keep it, recycle it, or dispose of it as you see fit. There are no extra charges or deposits to worry about.