Is Your GM SUV Experiencing Strange Electrical Problems?
If your Chevrolet Trailblazer, GMC Envoy, Oldsmobile Bravada, or other compatible GM SUV is suffering from flickering lights, malfunctioning power windows and locks, or a frustrating no-start condition, a failing Body Control Module (BCM) is the most likely culprit. The BCM is the central nervous system for your vehicle’s electronic accessories, and when it fails, it can cause a wide range of confusing and unpredictable issues. Don’t let a faulty module keep your reliable SUV off the road. This direct-fit BCM is the solution you need to restore full functionality and peace of mind.
From the Diagnostic Bay
We had a 2004 Trailblazer in the shop that was draining its battery overnight. The owner had already replaced the battery twice and the alternator once, but the parasitic draw persisted. A quick check with an ammeter showed a significant draw even after the vehicle was shut down. After pulling fuses one by one, we isolated the draw to the BCM circuit. The module had an internal short that was keeping the courtesy light relay energized, even though the lights themselves weren’t on. Swapping in a correctly programmed BCM solved the problem instantly. It’s a classic example of how a faulty BCM can create phantom issues that seem unrelated to the module itself.
Symptoms of a Failing Body Control Module
- ✔ Erratic or non-functional interior and exterior lights.
- ✔ Power windows, door locks, or mirrors working intermittently or not at all.
- ✔ The security or anti-theft light stays on, preventing the engine from starting.
- ✔ Inaccurate or dead gauges on the instrument cluster.
- ✔ Unexplained battery drain that kills the battery overnight.
- ✔ Horn honking unexpectedly or not working when pressed.
- ✔ Problems with the HVAC (heating and air conditioning) controls.
The Plug-and-Play Solution: A Programmed 2002-2005 GM SUV BCM
Replacing a BCM used to mean a trip to the dealership for expensive programming and calibration. We eliminate that hassle. When you order from us, we flash the module with the latest GM software updates and program it specifically to your vehicle’s VIN. This ensures that it communicates perfectly with your SUV’s other computers right out of the box. This is not a generic, one-size-fits-all part; it is a component prepared specifically for your vehicle’s unique configuration.
Simple Installation Process
This BCM is typically located on or near the front interior fuse box. Installation is straightforward for a DIY mechanic with basic tools. Once installed, your vehicle will regain control over its essential body functions. However, please be aware of potential post-installation procedures:
- Airbag System Sync: In some cases, the airbag warning light may illuminate after installation. This is because the new BCM needs to be synchronized with the SDM (airbag module). A professional scan tool is required to perform the ‘Setup SDM Primary Key in BCM’ procedure to clear the light.
- Brake Pedal Position Relearn: A brake pedal position sensor recalibration might be necessary to ensure your brake lights and traction control system function correctly. This can also be performed with a compatible diagnostic tool.
Guaranteed Compatibility
This module is a direct replacement for the following part numbers: 15122670, 15065293, 15114669, 15191621, and 9352135. It is designed to fit a wide range of 2002-2005 GM SUVs, including the Chevrolet Trailblazer & EXT, GMC Envoy, Envoy XL & XUV, Oldsmobile Bravada, Buick Rainier, Isuzu Ascender, and Saab 9-7X. Please verify your part number and check the fitment list to ensure this is the correct part for your vehicle.
Frequently Asked Questions
Do I need to have this BCM programmed by a dealer?
No. We handle all the programming for you before we ship the part. Simply provide us with your vehicle’s VIN during or after checkout, and it will arrive ready to install.
What is a BCM and what does it control?
The Body Control Module (BCM) is a computer that manages many of your vehicle’s non-engine-related functions. This includes power windows, locks, lights, wipers, the security system, and the instrument cluster.
Where is the BCM located on my Trailblazer or Envoy?
On most GMT360 platform vehicles (Trailblazer, Envoy, etc.), the BCM is integrated with or located right next to the interior fuse panel, typically under the driver’s side of the dashboard or under the rear seat.
What if the airbag light comes on after I install it?
This is a normal possibility. It means the BCM needs to be synced with the airbag module (SDM). A procedure called ‘Setup SDM Primary Key in BCM’ must be performed with a professional-grade scan tool to resolve this.
Is there a core charge for my old part?
No, there is no core charge for this part. You can keep your original module without needing to send it back to us.