Restore Your Truck’s Electrical System and Drive with Confidence
If you’re dealing with bizarre electrical issues in your 1998-2000 Chevy Blazer, S10, GMC Jimmy, or another compatible GM truck, you know how frustrating it can be. One minute the power locks work, the next they don’t. The dome light has a mind of its own, or worse, the security light prevents your truck from starting. These aren’t random glitches; they’re classic signs of a failing Body Control Module (BCM). As the central command for your vehicle’s body electronics, a faulty BCM can wreak havoc. This replacement module, part number 16257125, is the definitive solution to get your truck back to 100% functionality.
The biggest hurdle with BCM replacement has always been the expensive and time-consuming trip to the dealership for programming. We eliminate that step entirely. Simply provide us with your vehicle’s VIN during checkout, and our technicians will flash this module with the latest official GM software specific to your truck. It arrives at your door ready to be installed, saving you time, money, and the headache of scheduling a service appointment.
From the Diagnostic Bay: The BCM Ghost
I once had a 1999 GMC Jimmy S15 in my shop that was driving the owner crazy. He’d already replaced the battery and the alternator trying to solve an intermittent no-start and flickering headlights. His battery would drain overnight for no apparent reason. When I hooked up my scan tool, I found no engine codes, but I saw several communication errors with the body systems. The real culprit wasn’t the charging system; it was the BCM. A failing relay inside the module was keeping certain circuits awake after the key was off, creating a parasitic draw. Swapping in a pre-programmed BCM like this one solved every single issue instantly. It’s a fix I’ve performed hundreds of times on these otherwise rock-solid GM trucks.
Common Signs of a Failing BCM
- ✔ Erratic or non-functional power windows, door locks, or mirrors.
- ✔ Interior or exterior lights that flicker, stay on, or won’t turn on at all.
- ✔ The security or anti-theft light is illuminated, possibly causing a no-start condition.
- ✔ Inaccurate or dead gauges on the instrument cluster.
- ✔ The radio or climate control system behaves unpredictably.
- ✔ Diagnostic trouble codes (DTCs) related to lost communication with the BCM (U-codes).
- ✔ Unexplained battery drain when the vehicle is parked.
A Straightforward Guide to Installation
- ✔ Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- ✔ Locate the BCM: On most Blazer, Jimmy, and S10 models, the BCM is located behind the passenger side of the dashboard, often near the glove box. On Silverado/Sierra models, it’s typically on the driver’s side behind the lower dash panel.
- ✔ Disconnect and Remove: Carefully unplug the electrical connectors from the old BCM. They have locking tabs that need to be depressed. Once disconnected, unbolt or unclip the module from its mounting bracket.
- ✔ Install the New Module: Mount the new BCM in the same location and securely reconnect all electrical connectors. You should hear a ‘click’ as they lock into place.
- ✔ Reconnect Power: Re-attach the negative battery terminal.
- ✔ Perform Final Checks: Turn the key to the ‘On’ position and test all body functions—lights, windows, locks, etc. Start the vehicle to ensure everything is operating correctly.
Important Post-Installation Notes
While this 1998-2000 Blazer S10 BCM is programmed for a direct installation, some vehicles may require a final sync procedure. If your airbag warning light is on after installation, a professional scan tool is needed to perform the ‘Setup SDM Primary Key in BCM’ procedure. Additionally, some models may require a ‘Brake Pedal Position Relearn’ to ensure proper brake light and traction control operation. These are standard GM procedures and can be performed by any qualified technician.
Will This Fit My Vehicle?
This module is a direct replacement for part number 16257125 and other interchangeable numbers like 19153625, 8191536250, and 09366801. It is guaranteed to fit the following vehicles with the specified options:
- 1998-2000 Blazer S10 / Jimmy S15: Body Control (BCM); (center dash), ID 16257125
- 1998-2000 S10 / S15 / Sonoma: Body Control (BCM); (center dash), ID 16257125
- 1999-2000 Silverado / Sierra 1500 & 2500: Body Control (BCM); (LH dash)
- 2000 Astro / Safari (GMC): Body Control (BCM); (LH dash)
- 1999-2000 Isuzu Hombre: Body Control (BCM); (LH dash)
- 1998 Bravada: Body Control (BCM); (center dash), w/extended build date (opt ZN4)
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) allows us to program the BCM with the exact software and settings your truck had from the factory, plus any new GM updates. This ensures perfect compatibility with your vehicle’s specific options and prevents system conflicts.
Is this a simple plug-and-play part?
Yes, for most vehicles. Because we program it before shipping, you can typically just install it and go. However, as noted, some vehicles may require a quick relearn procedure for the airbag or brake systems with a scan tool if a warning light appears.
Where is this 1998-2000 Blazer S10 BCM located?
In the 1998-2000 Blazer S10 and Jimmy S15, the BCM is typically found behind the dashboard on the passenger side, accessible by removing the glove box or lower dash trim.
What happens if my airbag light is on after installation?
This is a known possibility. It means the new BCM needs to be synced with the airbag’s Sensing and Diagnostic Module (SDM). A technician with a professional-grade scan tool can perform the ‘Setup SDM Primary Key in BCM’ procedure in a few minutes to resolve this.
Do I need to send my old BCM back?
No. There is no core charge for this part. You can keep your original module.