Restore Your Truck’s Brain and Get Back to Work
Is your 1999-2000 GMC Sierra 2500 acting up? Unexplained stalling, erratic shifting, a persistent check engine light, or a no-start condition can often point to one culprit: a failing Powertrain Control Module (PCM). As the central computer for your engine and transmission, its health is critical to your truck’s performance and reliability. This isn’t just a part; it’s the command center for your vehicle. When it fails, it can create a host of frustrating and difficult-to-diagnose problems.
We take the guesswork and hassle out of the repair. This replacement PCM, compatible with part numbers 19109040, 09354896, and 9354896, arrives at your door fully programmed to your truck’s specific Vehicle Identification Number (VIN). We flash it with the latest GM-certified software updates, ensuring optimal performance, fuel economy, and emissions control. This means you can skip the expensive trip to the dealership for programming—a savings of both time and money.
From the Diagnostic Bay: The Ghost in the Machine
I remember a 2000 Sierra 2500 that came into my shop with a maddeningly intermittent no-start condition. The owner had already replaced the battery, starter, and fuel pump. It would run fine for days, then refuse to crank. After checking all the usual suspects, we hooked up a high-level scanner and monitored the data stream. We noticed that during the no-start events, the PCM wasn’t sending the ‘crank’ signal to the starter relay. There were no hard codes, just a ghost in the machine. It turned out to be an internal PCM failure on the logic board. Swapping in a VIN-programmed module like this one solved the problem instantly. It’s a perfect example of how a faulty PCM can mimic other component failures, making a direct-fit, pre-programmed solution invaluable for an accurate and efficient repair.
Is Your GM Truck Exhibiting These Symptoms?
A failing PCM can manifest in numerous ways. If you’re experiencing any of the following, your engine computer could be the root cause. This is especially true if you see diagnostic trouble codes (DTCs) like P0601, P0602, P0606, or other communication errors.
- ✔ The engine cranks but will not start.
- ✔ Persistent and unexplained Check Engine Light.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ A noticeable drop in fuel economy.
- ✔ The vehicle stalls for no apparent reason.
- ✔ Communication loss with the diagnostic scan tool.
- ✔ Misfires or rough running conditions.
A Straightforward Guide to Installation
Replacing the 1999-2000 Sierra 2500 PCM is a job most DIY mechanics can handle in their own driveway. On these trucks, the module is conveniently located in the engine bay, on the driver’s side, just below the battery tray.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 10 minutes for the system capacitors to discharge.
- Locate the PCM: Find the module under the battery tray on the driver’s side front of the engine compartment. You will likely need to remove the battery to gain access.
- Disconnect Connectors: Carefully unclip the wiring harness connectors from the old PCM. These connectors have locking tabs; be gentle to avoid breaking them.
- Remove the Old Module: Unbolt the PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed PCM into the bracket and securely re-fasten the bolts.
- Reconnect Everything: Plug the wiring harnesses back into the new module until they click firmly into place. Reinstall the battery and connect the negative terminal.
- Perform Security Relearn: You will need to perform a simple security relearn procedure so the vehicle recognizes the new PCM. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’, and repeating two more times before starting the engine. Consult your owner’s manual for the exact procedure for your vehicle.
Verified Vehicle Compatibility
This module is a direct-fit replacement for a wide range of General Motors vehicles. Please verify your part number and vehicle application from the list below. The programming we perform is specific to the VIN you provide.
- CAMARO 1999-2002 (5.7L)
- CORVETTE 1999-2000
- FIREBIRD 1999-2002 (5.7L)
- SIERRA 1500 PICKUP 1999-2000 (8 cylinder)
- SIERRA 2500 PICKUP 1999-2000
- SILVERADO 1500 PICKUP 1999-2000 (8 cylinder)
- SILVERADO 2500 PICKUP 1999-2000
- SUBURBAN 1500 & 2500 2000
- TAHOE 2000 (Silverado style)
- YUKON 2000 (exc. Denali)
- YUKON XL 1500 & 2500 2000
Frequently Asked Questions
Frequently Asked Questions
How does the VIN programming process work?
After you complete your purchase, you will need to provide us with your vehicle’s 17-digit VIN. We use this number to access the latest official GM software for your specific vehicle and flash it onto the module before shipping. This ensures it works perfectly with your truck’s engine, transmission, and options.
Is this part difficult to install myself?
No, for most individuals with basic mechanical skills, this is a straightforward replacement. The module is typically easy to access, and our pre-programming service eliminates the most difficult step—the need for specialized dealer tools.
Will I need to do any other programming after installation?
You will need to perform a simple ‘Security Relearn’ or ‘Key Relearn’ procedure. This does not require any special tools and can be done in your driveway with just the ignition key. It syncs the new PCM with your vehicle’s anti-theft system.
What is the difference between a PCM and an ECM?
The terms are often used interchangeably. ECM (Engine Control Module) typically just controls engine functions. A PCM (Powertrain Control Module) is more comprehensive, managing both the engine and the automatic transmission, which is the case for this GM module.
Is this a new or used part?
This is a quality, inspected, and tested recycled OEM part that has been verified to be fully functional before being programmed with your vehicle’s specific software.