If you’re dealing with bizarre electrical problems in your 2002-2005 GMC Envoy or a related GM SUV, you’ve come to the right place. As a technician with over two decades of experience, I’ve seen firsthand how a failing Body Control Module (BCM) can turn a reliable vehicle into a source of constant frustration. Flickering lights, malfunctioning power windows, or a dashboard that lights up with random warnings are classic signs that the BCM, your vehicle’s central nervous system for body electronics, is on its way out. This isn’t just an annoyance; it can affect critical systems.
We offer a dependable and straightforward solution: a replacement Body Control Module, part number 9352135, that arrives at your door pre-programmed to your vehicle’s specific VIN. This crucial step means you can bypass the expensive trip to the dealership for programming. We flash the module with the latest GM software updates, ensuring optimal performance and compatibility right out of the box. Simply provide your VIN during checkout, and we’ll handle the complex part, so you can focus on the installation.
Is Your SUV Showing These Symptoms?
A faulty BCM can manifest in numerous ways. If you’re experiencing any of the following, this module is likely the solution you need:
- ✔ Erratic or non-functional power windows, door locks, or interior lights.
- ✔ Headlights or taillights staying on or not working at all.
- ✔ The security light is on, or the vehicle won’t start intermittently.
- ✔ Unresponsive radio or climate control functions.
- ✔ Diagnostic trouble codes (DTCs) related to communication errors, such as U-codes (e.g., U0140, U0155).
- ✔ The horn sounding off randomly or not working when pressed.
A Technician’s Notebook
I remember a 2004 Trailblazer that came into my shop with a laundry list of electrical gremlins. The owner was fed up; his power windows had a mind of their own, and the interior lights would flicker constantly. A quick scan showed multiple communication loss codes with various modules. The BCM on these GMT360 platform trucks is integrated with the under-hood fuse block, making it susceptible to moisture damage from a leaking windshield cowl seal. After confirming power and ground, we replaced the BCM. With a pre-programmed unit like this one, the job was a simple swap, and all the strange issues vanished instantly. It’s a common failure point I’ve diagnosed hundreds of times.
A Straightforward Guide to Your 2002-2005 Envoy BCM Installation
This is a job most DIY enthusiasts can handle with basic tools. The BCM is located in the under-hood fuse box on the driver’s side. Follow these general steps for a successful replacement.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait a few minutes to ensure all systems are powered down.
- Access the Module: Open the hood and locate the main fuse box on the driver’s side. Remove the cover.
- Disconnect Connectors: Carefully unclip and disconnect all the large electrical connectors attached to the fuse box/BCM assembly. Take a photo beforehand if it helps you remember their positions.
- Remove the Old Unit: Unfasten the clips or bolts holding the fuse box assembly in place and lift it out of the engine bay.
- Install the New BCM: Place your new, pre-programmed BCM into the vehicle and secure it. Reconnect all electrical connectors firmly until they click into place.
- Power Up: Reconnect the negative battery terminal. Turn the key to the ‘On’ position (without starting the engine) for 10-15 seconds to allow the systems to initialize before starting the vehicle.
- Final Checks: Test all functions: windows, locks, lights, radio, etc. Refer to the post-installation procedures below if any warning lights appear.
Important Post-Installation Notes
While this module is programmed for plug-and-play installation, some vehicles may require additional steps:
- Airbag System Sync: If the airbag warning light is on after installation, a ‘Setup SDM Primary Key in BCM’ procedure is needed. This requires a professional-grade scan tool to sync the new BCM with the airbag system.
- Brake Pedal Position Relearn: On some models, a brake pedal position sensor recalibration may be necessary to ensure correct brake light operation and traction control function.
Disclaimer: Procedures can vary. Always consult a factory service manual or a qualified technician for guidance specific to your vehicle.
Verified Vehicle Compatibility
This BCM is a direct replacement for part numbers 15122670, 15065293, 15114669, 15191621, and 9352135. It is confirmed to fit the following models:
Buick Rainier: 2004-2005 (w/o security system)
Chevrolet Trailblazer & Trailblazer EXT: 2002-2005 (w/o security system for 03-05)
GMC Envoy, Envoy XL, Envoy XUV: 2002-2005 (w/o security system for 03-05)
Isuzu Ascender: 2003-2005 (w/o security system)
Oldsmobile Bravada: 2002-2004 (w/o security system for 03-04)
Saab 9-7X: 2005
Frequently Asked Questions
Do I need to send my old BCM back?
No, there is no core charge for this part. You can keep your original module.
What is a VIN and why do you need it?
The VIN is your vehicle’s unique 17-digit identification number. We use it to load the exact factory software and settings for your specific vehicle, ensuring a perfect match and proper function.
Is this a difficult part to install myself?
For most individuals with basic mechanical skills and tools, this is a straightforward replacement. The BCM is integrated with the under-hood fuse box, making it easy to access. Please review our installation guide above.
What if the airbag light comes on after I install it?
This can happen occasionally. It means the new BCM needs to be electronically ‘introduced’ to the airbag module. This procedure, called ‘Setup SDM Primary Key,’ must be done with a high-level diagnostic scan tool, often by a professional mechanic.
Will this fix my ‘Service 4WD’ light?
While the BCM communicates with many systems, a ‘Service 4WD’ light is more often caused by the Transfer Case Control Module (TCCM) or the front axle actuator on these trucks. It’s best to get a proper diagnosis before replacing parts.