Restore Your Truck’s Brain and Bring It Back to Life
Is your trusty 1998 or 1999 Chevy 1500 suddenly acting up? Maybe it’s hard to start, stalling at stoplights, or the check engine light is a permanent fixture on your dash. As a technician with over two decades of experience under the hood, I’ve seen these symptoms countless times. More often than not, the root cause is a failing Powertrain Control Module (PCM)—the computer that serves as the engine’s brain. When it falters, everything from fuel delivery to spark timing and transmission shifting can become erratic.
This isn’t just an annoyance; it affects your truck’s reliability, fuel economy, and safety. But the fix doesn’t have to involve a costly trip to the dealership. We offer a dependable, straightforward solution: a genuine, used OEM 1998-1999 Chevrolet 1500 PCM that is professionally programmed to your truck’s specific Vehicle Identification Number (VIN) before it ever leaves our facility. This ensures it communicates perfectly with your vehicle’s systems right out of the box.
Case Study: A Tricky Diagnosis
I remember a ’99 Silverado that came into my shop with a complaint of intermittent stalling and a harsh 1-2 shift. The owner had already replaced the fuel pump and a few sensors with no luck. The codes were all over the place—random misfires, O2 sensor faults—a classic sign of a confused computer. After confirming power and ground to the PCM were solid, we knew the module itself was the issue. A replacement, programmed PCM like this one solved every single problem in under an hour. The customer couldn’t believe the difference. It’s a common story for these otherwise bulletproof GMT400 trucks.
Is Your Truck Showing These Symptoms?
A failing PCM can manifest in many ways. If you’re experiencing any of the following, your engine computer is a likely suspect:
- ✔ Check Engine Light is on with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (PCM Processor Fault).
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained drops in fuel economy.
- ✔ Rough or inconsistent idling.
- ✔ The transmission shifts harshly or at the wrong times.
- ✔ Stalling for no apparent reason, either while driving or at a stop.
- ✔ Failure to pass an emissions test.
A Straightforward Guide to Installation
Replacing the 1998-1999 Chevrolet 1500 PCM is a job most DIYers can handle with basic tools. Because we program it for you, you get to skip the most complicated step!
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On most of these trucks, the PCM is located in the engine compartment on the driver’s side, near the fender or firewall.
- Disconnect the Connectors: Carefully unclip and remove the wiring harness connectors from the old PCM. They are color-coded, making re-connection simple.
- Remove the Old Module: Unbolt the old 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 secure the bolts.
- Reconnect and Secure: Plug the wiring harnesses back into the correct slots on the new PCM. You should hear a click as they lock into place.
- Reconnect the Battery: Re-attach the negative battery terminal.
- Security Relearn Procedure: You may need to perform a simple security relearn procedure. Turn the key to the ‘ON’ position for 10-15 minutes, then turn it ‘OFF’ for 10 seconds. Repeat this cycle three times. On the final cycle, the truck should start and run normally. This syncs the new PCM with your vehicle’s anti-theft system.
Verified Vehicle Compatibility
This module, identified by service ID 09355699, is a direct replacement for part number 09366810 and other interchangeable numbers. It is guaranteed to fit a wide range of GM trucks and vans. Please verify your part number or contact us with your VIN to ensure perfect compatibility.
This part is a confirmed fit for the following vehicles (and more) with service ID 09355699:
- 1998-1999 Chevrolet/GMC 1500, 2500, 3500 Pickups (Gasoline)
- 1998-1999 Chevrolet Tahoe & Suburban (Gasoline)
- 1998-1999 GMC Yukon & Suburban (Gasoline)
- 1999 Cadillac Escalade
- 1998-1999 Chevrolet Express & GMC Savana Vans (1500/2500/3500, Gasoline)
- 1998 Chevrolet Astro & GMC Safari
- 1998 Oldsmobile Bravada, Chevrolet S10 Blazer, GMC S15 Jimmy/Sonoma (4.3L)
- 1998 Isuzu Hombre (4.3L)
This quality used 1998-1999 Chevrolet 1500 PCM is your most reliable and cost-effective path to getting your truck back on the road and running strong.
Frequently Asked Questions
How does the VIN programming work?
After you place your order, you will need to provide us with your 17-digit Vehicle Identification Number (VIN). Our technicians use this number to flash the module with the correct, latest GM-approved software for your truck’s specific engine, transmission, and options. This ensures it works perfectly upon installation.
Is this a new part?
No, this is a genuine OEM part that has been sourced from a salvaged vehicle. Each unit is inspected and tested to ensure it is fully functional before being programmed and shipped. This provides OEM reliability at a fraction of the cost of a new module.
Do I need special tools to install this?
No special tools are required. Basic hand tools like a socket set are all you need for the physical installation. Because we handle the programming, you do not need an expensive dealership-level scan tool.
What if my part number is slightly different?
This module is a direct replacement for several part numbers, including 09355699, 16266645, 16250279, and more. As long as your vehicle is on the compatibility list and your original module has service ID 09355699, this part will work. When in doubt, send us your VIN, and we’ll confirm the fit for you.
What is a ‘CASE Relearn’ and will I need to do one?
A Crankshaft Variation Relearn (CASE Relearn) synchronizes the PCM with the crankshaft position sensor. While the truck will run without it, you may have a check engine light with code P1336. Most local repair shops can perform this quick procedure with a capable scan tool if needed.