Restore Full Electrical Function to Your GM SUV
Are you battling frustrating and unpredictable electrical issues in your Chevy Trailblazer, GMC Envoy, or other GMT360 platform SUV? Symptoms like erratic power windows, flickering lights, malfunctioning climate controls, or even a no-start condition often point to a single culprit: a failing Body Control Module (BCM). The BCM acts as the central nervous system for your vehicle’s body electronics, and when it starts to fail, it can cause a cascade of bizarre problems. This replacement module, part number 15122670, is the definitive solution to restore your vehicle’s proper operation and your peace of mind.
From the Diagnostic Bay
We had a 2004 Chevy Trailblazer come in that was driving the owner crazy. The radio would randomly turn off, the dome light would flicker, and the driver’s side window would only work on Tuesdays… or so it seemed. The dashboard was lit up with random warnings. After hours of chasing wires and checking grounds, we traced it all back to a failing BCM. The internal logic and relays were shot. Swapping in a correctly programmed BCM like this one had the truck behaving perfectly in under an hour. It’s amazing how one module can cause so much chaos.
Common Symptoms of a Failing BCM
- ✔ Erratic power window or door lock operation.
- ✔ Interior or exterior lights not working correctly (staying on or not turning on).
- ✔ Instrument cluster gauges behaving strangely or warning lights appearing without cause.
- ✔ HVAC (climate control) system malfunctions.
- ✔ Vehicle security system issues or false alarms.
- ✔ Intermittent no-start conditions where the engine cranks but won’t fire due to security system confusion.
- ✔ Communication errors with other modules when scanned with a professional diagnostic tool.
The Plug-and-Program Solution for Your Trailblazer Body Control Module
Don’t waste time and money at the dealership with a blank module that requires expensive programming. We take the hassle out of the repair. When you purchase this BCM, we will flash it with the latest GM software updates specifically for your vehicle using the VIN you provide. This ensures that the module is ready for installation right out of the box, integrating seamlessly with your vehicle’s existing systems. This process restores factory functionality and addresses many of the software-related issues that may have developed over time.
Simple Installation Process
This BCM is located on the front fuse box. While the physical replacement is straightforward for a DIY-er with basic tools, some post-installation electronic procedures may be necessary to ensure all systems communicate correctly. Please review the following potential requirements:
- Airbag System Sync: If the airbag warning light is illuminated after installation, a ‘Setup SDM Primary Key in BCM’ procedure must be performed with a professional-grade scan tool. This syncs the new BCM with the airbag system’s Sensing and Diagnostic Module (SDM).
- Brake Pedal Position Relearn: In some cases, a brake pedal position sensor recalibration might be needed. This is crucial for the proper function of your brake lights and the vehicle’s traction control system.
Disclaimer: Specific procedures can vary by exact year and model. Always consult a factory service manual or a qualified technician for guidance.
Guaranteed Fitment
This module is a direct replacement for a wide range of 2002-2005 GM SUVs. It is compatible with part numbers 15122670, 15065293, 15114669, 15191621, and 9352135. It fits models including the Chevy Trailblazer & Trailblazer EXT, GMC Envoy, Envoy XL & XUV, Oldsmobile Bravada, Buick Rainier, Isuzu Ascender, and Saab 9-7X. Please verify your part number and vehicle options to ensure compatibility.
Frequently Asked Questions
What is a Body Control Module (BCM)?
The BCM is a computer in your vehicle responsible for managing and controlling various electronic accessories, such as power windows, locks, lighting, wipers, and the security system. It’s the command center for passenger comfort and convenience features.
Is this BCM a direct plug-and-play installation?
Because we program it to your VIN, it is as close to plug-and-play as possible. However, as noted, some vehicles may require additional relearn procedures for the airbag or brake systems using a professional scan tool to complete the installation.
Do I need to send my old BCM back?
No. There is no core charge for this part. You can keep your original module, which can be helpful for double-checking part numbers or for any future reference.
What information do you need to program the module?
After you place your order, you will need to provide us with your vehicle’s 17-digit Vehicle Identification Number (VIN). This allows us to load the correct software and calibration files for your specific make, model, and options.
What happens if my airbag light is on after installation?
This is a known possibility. It means the new BCM needs to be electronically ‘introduced’ to the airbag system’s computer. A technician with a high-level scan tool can perform the ‘Setup SDM Primary Key in BCM’ procedure to resolve this.
Will this fix my specific electrical problem?
If your vehicle’s symptoms match the common signs of BCM failure and a proper diagnosis has been performed, this part is the correct solution. A faulty Trailblazer Body Control Module is a very common cause for the issues listed on this page.