Restore Your Truck’s Performance and Reliability
As a technician with over two decades of experience under the hood, I’ve seen my fair share of frustrating electrical gremlins. If your 1999-2000 Chevrolet 2500 Pickup is suddenly stalling, shifting erratically, or refusing to start, the Powertrain Control Module (PCM) is often the culprit. It’s the brain of your truck’s engine and transmission, and when it fails, it can cause a cascade of confusing problems. This isn’t just a part; it’s the central command for your vehicle’s most critical functions. We’re offering a reliable, plug-and-play solution to get your workhorse back on the road without the dealership hassle or expense.
This PCM is meticulously prepared and flashed with the latest GM software updates, specifically matched to your truck using your Vehicle Identification Number (VIN). This critical step ensures that all systems—from fuel delivery and ignition timing to transmission shift points—operate exactly as the factory intended. By purchasing a pre-programmed module, you’re bypassing the need for expensive specialty tools or a trip to the dealer for programming. This is the most direct path to resolving those stubborn check engine lights and performance issues for your 1999-2000 Chevrolet 2500 PCM.
From the Diagnostic Bay: A Technician’s Notebook
I remember a 2000 Chevy 2500 that came into my shop with a complaint of intermittent stalling at stoplights and a harsh 1-2 shift. The owner had already replaced the fuel pump and a few sensors with no luck. The scanner showed a P0601 code (Internal Control Module Memory Check Sum Error), a dead giveaway for a failing PCM. The internal memory was corrupted, causing it to send faulty commands. We swapped in a VIN-programmed module just like this one, performed the security relearn, and the truck ran like new. It’s a classic failure on these GMT400 and early GMT800 platform vehicles, and this is the definitive fix.
Common Signs of a Failing PCM
- ✔ Check Engine Light is on with codes like P0601, P0605, or U-series communication codes.
- ✔ Your engine cranks but refuses to start.
- ✔ Unexplained stalling or rough idling, especially when warm.
- ✔ Harsh, erratic, or delayed automatic transmission shifting.
- ✔ A noticeable drop in fuel economy.
- ✔ Communication errors with your OBD-II scan tool.
- ✔ Other modules, like the ABS or instrument cluster, acting erratically.
A Straightforward Guide to Installation
- ✔ Safety First: Disconnect the negative terminal from your truck’s battery to prevent any electrical shorts.
- ✔ Locate the PCM: On most Chevrolet/GMC pickups and full-size vans from this era, the PCM is located in the engine compartment on the driver’s side, often near the fender or firewall.
- ✔ Disconnect the Connectors: Carefully unclip and remove the wiring harness connectors from the old module. They are color-coded and keyed, so you can’t mix them up.
- ✔ Swap the Module: Unbolt the old PCM from its bracket and set it aside. Mount the new module in its place and secure it.
- ✔ Reconnect Everything: Plug the wiring harnesses firmly back into the new PCM until they click. Reconnect the negative battery terminal.
- ✔ Perform Security Relearn (Crucial Step): Your vehicle’s anti-theft system (PassLock/VATS) needs to sync with the new PCM. The standard procedure is: Turn the key to ‘ON’ for 10-11 minutes until the ‘Security’ light goes out, then turn the key ‘OFF’ for 30 seconds. Repeat this cycle two more times for a total of three cycles. On the fourth try, the vehicle should start and run.
With this replacement 1999-2000 Chevrolet 2500 PCM, you are not just buying a part; you are getting a reliable solution that restores your vehicle’s core functionality and gives you peace of mind.
Verified Vehicle Compatibility
This module, identified by part number 16263494, is a direct replacement for a wide range of GM trucks and vans. It is also compatible with service numbers 16265035, 8162634940, 218-11787, and 21811787. Please verify your vehicle is on the list below. If you have any questions about fitment, don’t hesitate to contact us with your VIN.
Fits various 1998-2002 Chevrolet, GMC, Cadillac, and Isuzu models including: Silverado, Sierra, S10/Sonoma, Blazer/Jimmy, Tahoe/Yukon, Suburban, Express/Savana, Astro/Safari, Escalade, Bravada, and Hombre equipped with compatible gasoline engines. It is critical to match the part number 16263494 or provide your VIN to ensure correctness.
Frequently Asked Questions
Do I really need to provide my VIN?
Yes, absolutely. Your VIN is essential for us to load the correct GM-certified software and calibrations for your specific engine, transmission, and emissions equipment. This ensures perfect compatibility and performance right out of the box.
Is the security relearn procedure difficult?
Not at all! It’s a simple key-on, key-off procedure that takes about 30 minutes and requires no special tools. We’ve outlined the steps above, and it’s a common procedure for any DIY mechanic.
Will this fix my transmission shifting problems?
In many cases, yes. The PCM controls the transmission’s electronic solenoids. If the PCM is failing, it can cause harsh shifts, slipping, or failure to shift. If your issues are caused by a faulty PCM, this part is the solution.
What if my original part number is different but on the compatible list?
The listed part numbers (like 16265035) are often hardware-identical service replacements or earlier versions. As long as your vehicle is on the fitment list and you provide your VIN, we will program this module to function perfectly as a replacement.
Why is this better than a part from a salvage yard?
A used part from a salvage yard will be programmed for a different vehicle and will not have the latest software updates. It won’t work correctly without being reprogrammed and carries the risk of having the same internal faults as your original. Our module is tested, cleared, and programmed specifically for YOUR truck.