Restore Peak Performance to Your GM Truck or Van
As a technician with over two decades of experience, I’ve seen firsthand the headaches a failing Powertrain Control Module (PCM) can cause. It’s the brain of your vehicle, and when it starts to glitch, you get a cascade of frustrating, often misdiagnosed, problems. Your dependable 1999-2000 Chevrolet 2500 PCM is responsible for everything from fuel mixture and spark timing to transmission shift points. When it fails, your truck simply won’t run right. This isn’t just a part; it’s the solution to getting your reliable workhorse back on the road, running smoothly and efficiently.
We take the guesswork and hassle out of the repair. Unlike a generic module from a parts store, this PCM arrives at your door specifically programmed for your vehicle. We use your Vehicle Identification Number (VIN) to flash the module with the latest, most stable software updates directly from GM. This critical step ensures all operating parameters are perfectly matched to your truck’s specific configuration, often correcting underlying drivability issues that existed even with the original factory software.
From the Diagnostic Bay
I remember a 2000 Chevy Express 2500 work van that came into my shop. The owner was at his wit’s end. He’d replaced the fuel pump and multiple sensors chasing an intermittent no-start and a harsh 1-2 shift that would rattle your teeth. The van would run fine for days, then refuse to start, with no codes stored. After checking grounds and power feeds to the PCM, we noticed the 5-volt reference signal would occasionally drop out. It was a classic case of an internally failing PCM. We installed a VIN-programmed module, performed the security relearn, and the van ran flawlessly. It wasn’t just fixed; the updated software made the transmission shift smoother than the owner could ever remember. That’s the difference a correctly prepared module makes.
Is Your GM Truck or Van Showing These Signs?
A faulty PCM can manifest in numerous ways. If you’re experiencing any of the following, a failing computer is a likely culprit:
- ✔ Persistent Check Engine Light (CEL), especially with communication error codes like P0601, P0605, or U-series codes.
- ✔ Engine stalling, stumbling, or refusing to start intermittently.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ A noticeable drop in fuel economy.
- ✔ The vehicle enters a “limp mode” with reduced power.
- ✔ Failure to pass an emissions or smog test.
A Straightforward Guide to Installation
This repair is well within the reach of a DIY enthusiast. With basic hand tools, you can have your truck running again in under an hour.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and secure it away from the post.
- Locate the PCM: On most of these trucks and vans, the PCM is located in the engine bay, typically on the driver’s side fender, near the battery, or on the core support. Consult your specific model’s service information if you’re unsure.
- Disconnect the Harnesses: Carefully release the locking tabs on the electrical connectors and pull them straight out from the module. Avoid pulling on the wires themselves.
- 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: Seat your new, pre-programmed PCM into the bracket and secure it with the original bolts.
- Reconnect and Secure: Plug the wiring harnesses back into the new module until they click firmly into place. Reconnect your negative battery terminal.
- Perform Security Relearn: This is a critical final step. Turn the key to the ‘ON’ position (without starting) for 10-15 minutes, then turn it ‘OFF’ for 10 seconds. Repeat this cycle two more times (3 cycles total). On the fourth attempt, the vehicle should start and run normally. This syncs the new PCM with your vehicle’s anti-theft system.
Verified Vehicle Compatibility
CHEVROLET 2500 PICKUP 99-00 (Gasoline, LH front engine)
CHEVROLET 3500 PICKUP 99-00 (Gasoline, LH front engine)
CHEVROLET 1500 PICKUP 99 (5.0L/5.7L, ID 16263494)
SILVERADO 1500 PICKUP 99-00 (4.3L V6, LH under battery)
TAHOE 99-00 (Classic Style, LH front engine)
SUBURBAN 1500/2500 99 (Gasoline, ID 16263494)
EXPRESS VAN 1500/2500/3500 99-02 (Gasoline)
GMC 1500/2500/3500 PICKUP 99-00 (Gasoline)
SIERRA 1500 PICKUP 99-00 (4.3L V6, LH under battery)
YUKON/YUKON DENALI 99-00 (LH engine/under battery)
SAVANA VAN 1500/2500/3500 99-02 (Gasoline)
S10/S15/SONOMA 98-00 (4.3L V6)
BLAZER/JIMMY 98-00 (4.3L V6)
ASTRO/SAFARI VAN 99-01 (ID 16263494)
CADILLAC ESCALADE 99-00
OLDSMOBILE BRAVADA 98-00
GMC ENVOY 98-00
ISUZU HOMBRE 98-00 (4.3L V6)
Note: Please verify your original part number or consult the detailed fitment list if unsure.
Frequently Asked Questions
What exactly is a Powertrain Control Module (PCM)?
The PCM is your vehicle’s main computer. It controls the engine and transmission functions by reading data from various sensors and making real-time adjustments to fuel delivery, ignition timing, and shift patterns to ensure optimal performance, fuel economy, and emissions.
Is this module truly plug-and-play?
It’s as close as it gets. Because we program it to your VIN, it’s ready for installation. The only additional step required is the simple, no-tools-needed security relearn procedure detailed in our installation guide. This syncs the module to your truck’s anti-theft system.
How do I provide my VIN after purchase?
After you complete your purchase, simply send us a message with your 17-digit Vehicle Identification Number (VIN). We cannot program and ship your module without it. You can find your VIN on your vehicle’s registration, insurance card, or on the driver’s side dashboard viewable through the windshield.
Will this fix my specific problem, like a check engine light?
If the root cause of your issue is a faulty PCM, then yes, this part will be the solution. It is a common fix for issues like internal memory errors (P0601), erratic behavior, and communication failures. However, always ensure you have performed proper diagnostics to rule out sensor or wiring issues.
What if my original part number is slightly different?
This module is compatible with several part numbers, including 16263494 and 16265035. As long as your vehicle is on the compatibility list and your original module looks physically identical, our VIN-based programming ensures it will function correctly as a replacement.