Restore Your GM Truck’s Performance and Reliability
Is your 1998-1999 Suburban 2500 acting up? If you’re dealing with frustrating issues like a persistent Check Engine Light, poor fuel economy, or erratic engine behavior, the Powertrain Control Module (PCM) is often the culprit. As the central computer of your vehicle, a failing PCM can cause a cascade of problems that are difficult to diagnose. Over my 20 years in the shop, I’ve seen countless GM trucks and vans sidelined by a faulty module. This isn’t just an inconvenience; it affects your vehicle’s safety and dependability.
We offer a straightforward, reliable solution. This is a tested, used OEM PCM that we program specifically to your vehicle’s Vehicle Identification Number (VIN). By providing your VIN at checkout, you receive a module with the latest GM software updates already installed. This means no expensive trips to the dealership for programming—it arrives at your door ready for a simple, direct installation. It’s the most efficient way to get your truck back to factory-spec operation.
A Technician’s Notebook
I remember a customer with a ’99 Tahoe—same platform as these Suburbans—that had a baffling intermittent no-start condition. It would crank but not fire, then an hour later, start perfectly. There were no consistent trouble codes, making it a diagnostic nightmare. After checking fuel pressure and spark, we suspected the PCM. The internal circuits can develop micro-fractures from heat and vibration over the years, causing these ghost-like problems. We installed a VIN-programmed PCM just like this one, and the problem was solved instantly. The customer went from considering selling the truck to having his reliable daily driver back.
Is Your Truck Showing These Symptoms?
A failing PCM can manifest in various ways. If you’re experiencing any of the following, it might be time for a replacement:
- ✔ Unexplained Check Engine Light, especially with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0605 (Internal Control Module ROM Error).
- ✔ Engine stalling, stumbling, or misfiring.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ A sudden, noticeable drop in fuel mileage.
- ✔ Complete no-start condition where the engine cranks but won’t turn over.
- ✔ Failure to pass an emissions or smog test.
A Straightforward Guide to Installation
Installing your pre-programmed 1998-1999 Suburban 2500 PCM is a job most DIYers can handle in under an hour with basic hand tools. This module is typically located in the engine bay on the driver’s side.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: Find the existing module in the engine compartment. It’s a metal box with several large multi-pin electrical connectors.
- Disconnect the Connectors: Carefully unclip and remove all electrical connectors from the old PCM. They often have locking tabs that need to be released.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Bolt your new, VIN-programmed PCM into the mounting bracket.
- Reconnect Everything: Firmly plug all electrical connectors into the new module. Ensure they click into place. Reconnect the negative battery terminal.
- Final Step: In some cases, a security relearn procedure may be necessary. This typically involves turning the key to the ‘ON’ position for 10-15 minutes. Consult your vehicle’s service information for specific steps if required.
Verified Vehicle Compatibility
This module, identified by service number 16266645 or ID 09355699 / 9355699, is a direct replacement for a wide range of GM vehicles. Please verify your part number or consult the list below. It is compatible with the following part numbers: 16250279, 16258815, 09366810, 9366810.
This ECM fits many 1998-1999 GM models including:
- Chevrolet/GMC C/K 1500, 2500, 3500 Pickups (Gasoline)
- Chevrolet Suburban 1500 & 2500 (Gasoline)
- Chevrolet Tahoe & GMC Yukon (Gasoline)
- Cadillac Escalade (1999)
- Chevrolet Express & GMC Savana 1500, 2500, 3500 Vans (Gasoline)
- Chevrolet Astro & GMC Safari Vans
- Chevrolet S10, GMC Sonoma, Oldsmobile Bravada, GMC Envoy, Isuzu Hombre (4.3L V6)
- Chevrolet Blazer S10 & GMC Jimmy S15 (4.3L V6)
Note: For 4.3L applications, this fits models without build date option ZN4. Always match your part number or ID 9355699 for guaranteed compatibility.
Why do you need my VIN?
We require your Vehicle Identification Number (VIN) to program the module with the correct GM software and calibrations for your specific vehicle. This ensures proper engine and transmission function, and makes the part ready for installation right out of the box.
Is this a new part?
No, this is a high-quality, tested used OEM part sourced from a salvaged vehicle. Each unit is inspected and verified to be fully functional before being programmed and shipped. This provides an affordable and reliable alternative to a new dealership part.
Will I need to do anything after installation?
In most cases, the module is plug-and-play. However, some GM vehicles of this era require a security relearn procedure (often called Passlock or Passkey) to allow the vehicle to start. This is a simple procedure that does not require special tools.
Does this fix transmission shifting problems?
Yes, the PCM controls both the engine and the transmission. A faulty module can cause poor shifting, hunting for gears, or delayed engagement. Replacing a bad PCM often resolves these transmission-related symptoms.
What if my part number isn’t an exact match?
This module replaces several part numbers. Please check the compatibility list. As long as your vehicle is listed and your original module has one of the compatible part numbers (like 16266645 or 09355699), this part will work for you.