Restore Peak Performance to Your Chevy Truck
If your trusty 1999-2000 Chevrolet 2500 is suddenly running rough, stalling, or throwing a persistent Check Engine Light, the problem often points directly to a failing Powertrain Control Module (PCM). As a technician with over two decades of experience under the hood, I’ve seen firsthand how a faulty PCM can cause a cascade of frustrating issues that are otherwise difficult to diagnose. It’s the brain of your truck’s engine and transmission, and when it starts to go, performance and reliability go with it.
This isn’t just a replacement part; it’s a complete solution. We take the guesswork and the expensive trip to the dealership out of the equation. Before we ship it, we program this PCM with the latest GM software updates, specifically matched to your truck’s Vehicle Identification Number (VIN). This ensures that once it arrives, it’s ready for a straightforward installation, restoring the precise fuel delivery, spark timing, and transmission shift points your vehicle had when it was new.
Case Study: The Ghost in the Machine
I remember a 2000 GMC Sierra (which uses this exact PCM) that came into my shop with an intermittent no-start condition that had two other shops stumped. The owner had already replaced the battery, alternator, and crank sensor. The truck would run fine for days, then refuse to start for no apparent reason. After hooking up my diagnostic scanner during one of its episodes, I noticed erratic data from multiple sensors simultaneously—a classic sign of a failing computer, not failing sensors. The internal processor of the original PCM was failing under certain temperature conditions. We installed one of our VIN-programmed PCMs, and the problem was solved instantly. The customer was thrilled to have his reliable workhorse back without wasting any more money on unnecessary parts.
Is Your Chevy Truck Showing These Signs of PCM Failure?
- ✔ Persistent Check Engine Light (CEL) that won’t clear.
- ✔ Diagnostic Trouble Codes (DTCs) like P0601 (Internal Memory Checksum Error) or P0606 (PCM Processor Fault).
- ✔ Unexplained stalling or rough idling.
- ✔ A sudden drop in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Engine cranks but refuses to start (no-start condition).
- ✔ Failure to pass state emissions testing.
A Straightforward Guide to Installation
One of the biggest benefits of our pre-programmed module is the ease of installation. You don’t need advanced diagnostic tools or a trip to the dealer. This is a job most DIYers can handle in their own driveway.
- Safety First: Always disconnect the negative terminal from your truck’s battery before starting any electrical work.
- Locate the PCM: On most 1999-2000 Chevy/GMC pickups, the PCM is located in the engine compartment on the driver’s side, often near the firewall or inner fender.
- Disconnect the Connectors: Carefully unclip the wiring harness connectors from the old module. They have locking tabs that may need to be gently pried up. Inspect the connectors for any corrosion or damage.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket.
- Install the New PCM: Bolt your new, pre-programmed PCM into place.
- Reconnect Everything: Firmly plug the wiring harnesses into the new module until they click into place. Reconnect the negative battery terminal.
- Final Steps: In some cases, a security relearn procedure may be necessary, which typically involves turning the key to the ‘On’ position for 10-15 minutes. Your truck is now ready to start!
Verified Fitment for Your GM Truck or Van
This Powertrain Control Module is a direct-fit replacement for a wide range of GM trucks and vans from the late 1990s and early 2000s. It is compatible with service numbers 16263494, 16265035, 8162634940, 218-11787, and 21811787. While it is the correct part for a 1999-2000 Chevrolet 2500 PCM, it also fits many other models including the Chevrolet Silverado, Suburban, Tahoe, Express Van, and their GMC counterparts like the Sierra, Yukon, and Savana, as well as the Cadillac Escalade, Chevy S10/Blazer, and more. Please verify your original part number or use the fitment chart to ensure compatibility.
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) allows us to load the exact, correct software calibration for your truck’s specific engine, transmission, and emissions equipment. This ensures perfect compatibility and performance, eliminating the need for dealer programming.
Is this a plug-and-play part?
Yes! Because we program it before shipping, it arrives ready to be installed. In most cases, you can simply swap the module and start the vehicle. Some models may require a simple, key-on security relearn procedure that takes about 10-15 minutes to complete.
Will this fix my transmission shifting problems?
In many GM vehicles of this era, the PCM also controls the transmission. If your shifting issues are caused by faulty electronic commands from a failing module, then yes, this part is very likely to resolve them by restoring proper communication and shift logic.
What if my original part number is not listed?
Please contact us with your VIN and original part number. GM often supersedes part numbers, and we can verify if this module is the correct, updated replacement for your specific vehicle.
Is this a difficult part for a DIYer to install?
Not at all. The physical replacement is typically very simple, requiring only basic hand tools to unbolt the old unit and install the new one. The most important part is the pre-programming, which we handle for you.