Restore Your GM Truck’s Brain and Get Back on the Road
If your trusty Chevy, GMC, or Cadillac truck or van is suddenly acting possessed—stalling, shifting erratically, or refusing to start—the problem often points to a failing Powertrain Control Module (PCM). As a technician with over two decades of experience, I’ve seen these symptoms countless times. The PCM is the central computer of your vehicle, managing everything from fuel mixture and ignition timing to transmission shifts. When it fails, your dependable workhorse can become a frustrating driveway ornament. This isn’t just a part; it’s the solution to get your vehicle running reliably again.
This is a thoroughly tested, used OEM PCM that we program specifically for your vehicle. Forget expensive dealership visits and the hassle of finding someone to flash a new module. You provide us with your Vehicle Identification Number (VIN) after purchase, and we handle the rest. We load the latest, most stable GM factory software for your exact vehicle configuration. This ensures that when the part arrives, it’s ready for a straightforward installation, restoring factory performance and communication between all your vehicle’s systems.
Case Study: A Tricky Diagnosis
A customer brought in his ’99 Suburban 1500 with a complaint that stumped two other shops. The truck would run fine for days, then suddenly die at a stoplight and refuse to restart for an hour. There were no consistent trouble codes, just a random U-code for lost communication every now and then. We checked grounds, power feeds, and the ignition system—all perfect. From experience, I know these intermittent, heat-related no-starts on GMT400 platforms are classic signs of a PCM with failing internal processors. We installed one of these VIN-programmed modules, and the problem was solved instantly. The customer saved hundreds compared to the dealership and avoided replacing unnecessary parts.
Is Your Truck or Van Showing These Symptoms?
A failing PCM can cause a wide range of issues. If you’re experiencing any of the following, this module is the likely solution, especially if you’ve ruled out more common failures like sensors or fuel pumps.
- ✔ Check Engine Light is on with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0605 (Internal Control Module ROM Error).
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained stalling, especially after the engine has warmed up.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ A noticeable drop in fuel economy.
- ✔ Failure to pass an emissions test due to communication errors.
- ✔ The anti-theft or security light stays on, preventing the engine from starting.
A Straightforward Guide to Installation
Installing your pre-programmed 1998-1999 Chevrolet 1500 PCM is a job most DIYers can handle in under 30 minutes with basic hand tools. Following these steps ensures a smooth process.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent any accidental reconnection.
- Locate the PCM: On most of these trucks and SUVs, the PCM is located in the engine compartment, typically on the driver’s side inner fender or near the battery.
- Disconnect the Connectors: Carefully unclip and remove the wiring harness connectors. These connectors have locking tabs; be gentle to avoid breaking them. Note their color and orientation.
- Remove the Old Module: Unbolt the PCM from its mounting bracket. There are usually two or three bolts holding it in place.
- Install the New Module: Mount your new, pre-programmed PCM onto the bracket and secure it with the bolts.
- Reconnect Everything: Firmly plug the wiring harnesses back into the correct sockets on the new PCM. You should hear a ‘click’ as they lock into place. Reconnect the negative battery terminal.
- Perform Security Relearn (If Necessary): In some cases, a security relearn procedure is required. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. Your vehicle’s service manual will have the exact procedure.
Verified Vehicle Compatibility
This module, identified by service number 9366810 (and interchangeable with 09355699, 16266645, and others), is the correct fit for a wide range of GM vehicles. While this is a 1998-1999 Chevrolet 1500 PCM, it also fits the models listed below. Please verify your part number or contact us with your VIN to ensure 100% compatibility.
- ✔ Chevrolet & GMC Pickups (1500, 2500, 3500) – 1998-1999
- ✔ Chevrolet & GMC Suburban/Tahoe/Yukon – 1998-1999
- ✔ Chevrolet Express & GMC Savana Vans (1500, 2500, 3500) – 1998-1999
- ✔ Cadillac Escalade – 1999
- ✔ Chevrolet Astro & GMC Safari Vans – 1998
- ✔ Oldsmobile Bravada, Chevrolet Blazer/S10, GMC Jimmy/Sonoma, Isuzu Hombre – 1998 (4.3L V6 models)
Frequently Asked Questions
Why do I need to provide my VIN?
Your VIN is essential. It allows us to access the exact GM database entry for your vehicle, ensuring we program the PCM with the correct software for your engine, transmission, tire size, and other factory options. This makes the installation plug-and-play.
Is this part difficult to install?
No, this is a very DIY-friendly repair. With basic hand tools, you can typically swap the module in under 30 minutes. Just disconnect the battery, unbolt the old unit, and plug in the new one. A security relearn may be needed, which is a simple key-cycle procedure.
Will this fix my no-start problem?
If your vehicle’s symptoms and diagnostic trouble codes point to a failed PCM, this part is the definitive solution. It’s the ‘brain’ of the engine management system, and when it fails, it commonly causes no-start or intermittent stalling conditions.
What does ‘used’ mean for this part?
This PCM is a genuine OEM part carefully sourced from a salvaged vehicle. Each unit is inspected and electronically tested to ensure full functionality before being programmed with fresh GM software for your vehicle.
Do I need any other parts or services?
No. Because we program the module for you before shipping, you will not need to take it to a dealer or mechanic for additional programming. It arrives ready to be installed.