Restore Peak Performance to Your GMT800 Truck
Is your 1999-2000 GMC Sierra 2500 running rough, shifting erratically, or refusing to start? These are classic signs of a failing Powertrain Control Module (PCM), the electronic brain of your vehicle. A faulty PCM can cause a cascade of frustrating issues, from poor fuel economy to a persistent Check Engine Light that leaves you guessing. This direct-fit replacement PCM, part number 9354896, is the definitive solution to restore your truck’s factory performance, drivability, and reliability.
The PCM is responsible for managing critical engine and transmission functions, including fuel injection timing, spark advance, transmission shift points, and emissions controls. When it begins to fail, the signals it sends become erratic, leading to inconsistent performance. Our replacement module eliminates the guesswork. We pre-program it using your truck’s specific Vehicle Identification Number (VIN), loading it with the latest GM-certified software updates. This ensures seamless communication with all other vehicle modules and guarantees compatibility right out of the box. No expensive trips to the dealership for programming are required.
From the Diagnostic Bay
We had a 2000 Silverado 2500 (a sister truck to the Sierra) come into the shop with a bizarre issue. The owner complained of intermittent stalling at stoplights and a transmission that felt like it was ‘hunting’ for gears. There were no consistent trouble codes, just a generic U-code for lost communication every now and then. We checked wiring, sensors, and grounds for two days straight. On a hunch, we connected a scope to the PCM’s main power and ground circuits. We found a significant voltage drop inside the module itself whenever the engine bay got hot. The internal circuits were failing under thermal load. We installed one of these VIN-programmed PCMs, and the truck ran perfectly. It’s often the central component that causes the most elusive problems.
Is Your Sierra 2500 Showing These Symptoms?
- ✔ Persistent and illuminated Check Engine Light (CEL)
- ✔ Engine stalling, stumbling, or misfiring
- ✔ Harsh or erratic automatic transmission shifting
- ✔ A complete no-start condition where the engine cranks but won’t fire
- ✔ Noticeable decrease in fuel economy
- ✔ Failure to pass state emissions testing
- ✔ Communication errors with diagnostic scan tools
The Critical Role of a Programmed 1999-2000 Sierra 2500 PCM
Unlike a simple sensor, a PCM is not a one-size-fits-all part. Your truck’s VIN contains specific information about its engine size, transmission type, axle ratio, and factory options. Our programming process uses this data to load the exact operational parameters your vehicle requires. This VIN-specific flashing is essential for proper function. Installing a non-programmed or incorrectly programmed module can lead to severe drivability problems or even prevent the vehicle from starting altogether. By providing us with your VIN upon purchase, you are ensuring a true plug-and-play installation experience. We handle the complex programming so you can focus on the straightforward physical installation.
This module is a direct replacement for OEM part numbers 9354896, 09354896, and 19109040. It is built to meet or exceed original equipment specifications, providing a durable and long-lasting repair. The process is simple: place your order, provide your VIN, and we ship a module that is ready for installation. In most cases, a security relearn procedure (often called a CASE relearn) may be required after installation, which can be performed with a capable scan tool or by following a simple key-cycle procedure.
Frequently Asked Questions
Do I need to have this PCM programmed by a dealer?
No. We program the module to your vehicle’s specific VIN before we ship it to you. It will arrive ready to be installed, saving you time and the high cost of dealership programming.
Where is the PCM located on my 1999-2000 Sierra 2500?
On these trucks, the Powertrain Control Module is typically located in the engine bay on the driver’s side, mounted to a bracket underneath or near the battery tray.
What information do you need from me?
After you complete your purchase, you will need to provide us with your vehicle’s 17-digit VIN (Vehicle Identification Number). This is crucial for us to load the correct software for your truck’s specific configuration.
Will this fix my Check Engine Light?
If the Check Engine Light is on due to an internal failure of the original PCM, then yes, this part will resolve the issue. However, it’s always recommended to have the codes read by a scanner to ensure the PCM is the root cause and not a separate sensor or wiring issue.
Is any other setup required after installation?
In some cases, a Crankshaft Variation Relearn (CASE Relearn) procedure is needed to prevent a P1336 trouble code. This procedure can be done with many professional-grade scan tools and synchronizes the PCM with the crankshaft position sensor.