Restore Full Electrical Function to Your GM SUV
Is your 2002-2005 Trailblazer, Envoy, or other GM SUV experiencing a host of bizarre electrical issues? From flickering lights and malfunctioning power windows to intermittent starting problems, the culprit is often a failing Body Control Module (BCM). The BCM acts as the central nervous system for your vehicle’s body electronics, and when it malfunctions, it can create frustrating and unpredictable problems. This replacement BCM is the definitive solution to restore your vehicle’s performance and reliability.
We take the guesswork and hassle out of the repair process. Unlike a generic module from a parts store or salvage yard, this BCM is professionally programmed specifically for your vehicle. Simply provide your VIN during checkout, and our technicians will flash the module with the latest GM software updates and your vehicle’s exact configuration. This ensures a seamless installation process, eliminating the need for an expensive trip to the dealership for programming.
From the Diagnostic Bay
We had a 2004 GMC Envoy come into the shop with a classic “parasitic draw” complaint. The owner had replaced the battery twice, but it would still be dead every few mornings. After checking all the usual suspects, we hooked up a scope to the BCM’s communication lines. We found that the module wasn’t entering its “sleep mode” correctly, keeping other modules awake all night and slowly draining the battery. Swapping in a correctly programmed BCM solved the issue instantly. It’s a perfect example of how a faulty BCM can cause symptoms that seem unrelated to its primary function.
Common Symptoms of a Failing BCM
- ✔ Erratic or non-functional interior and exterior lights (headlights, dome lights, dash lights).
- ✔ Power windows, door locks, or mirrors operating intermittently or not at all.
- ✔ The security or anti-theft system light staying on, preventing the engine from starting.
- ✔ Gauges on the instrument cluster behaving erratically or not working.
- ✔ Unexplained battery drain that kills the battery overnight.
- ✔ Radio or climate control systems malfunctioning.
- ✔ Horn honking unexpectedly or not working when pressed.
Your Direct-Fit 2002-2005 Trailblazer BCM Solution
This module is a direct replacement for a wide range of GM SUVs built on the GMT360 platform, including the Chevrolet Trailblazer, GMC Envoy, Oldsmobile Bravada, Buick Rainier, Isuzu Ascender, and Saab 9-7X. It is compatible with multiple original part numbers, including 15122670, 15065293, 15114669, 15191621, and 9352135. By providing your VIN, you guarantee that the 2002-2005 Trailblazer BCM you receive is perfectly matched to your vehicle’s specific options, whether it has a security system or not.
Installation and Post-Install Considerations
Installation is straightforward for those with moderate mechanical skill. The BCM is typically located on or near the front fuse box. After swapping the module, some vehicles may require additional procedures to ensure all systems communicate correctly. If your airbag warning light illuminates, a professional scan tool will be needed to perform the ‘Setup SDM Primary Key in BCM’ procedure. Similarly, a ‘Brake Pedal Position Relearn’ may be necessary for proper brake light and traction control function. Please note that while our programming handles the majority of the setup, these final sync procedures are sometimes required for full system integration. Best of all, there is no core charge, so you can keep your original module.
Frequently Asked Questions
What does the Body Control Module (BCM) do?
The BCM is a computer that manages and controls many of your vehicle’s non-engine related electronic functions. This includes power windows, door locks, interior and exterior lighting, the security system, wipers, and more.
Do I need to get this BCM programmed by a dealer?
No. We handle the programming for you before we ship the part. Just provide your vehicle’s VIN at checkout, and the module will arrive ready to be installed, flashed with the latest GM software for your specific vehicle.
Where is the BCM located on a 2003 Trailblazer or Envoy?
On most of these GM SUV models, the BCM is located in the front of the vehicle, integrated with or attached to the side of the interior fuse box, typically under the driver’s side of the dashboard.
What happens if my airbag light comes on after installation?
This can happen occasionally. It means the new BCM needs to be electronically ‘introduced’ to the airbag system’s computer (SDM). A repair shop with a professional-grade scan tool will need to perform the ‘Setup SDM Primary Key in BCM’ procedure to sync the modules and turn off the light.
Is this part compatible if my original part number is 15122670?
Yes, this BCM is a direct replacement for several part numbers, including 15122670, 15065293, 15114669, 15191621, and 9352135. Our VIN programming ensures it will function correctly in place of any of these original parts.