Restore Peak Performance to Your GM Truck or Van
Is your GMC 3500, Chevrolet Express, or other compatible GM vehicle suffering from perplexing issues like a persistent check engine light, poor fuel economy, erratic shifting, or even a no-start condition? These are classic signs of a failing Powertrain Control Module (PCM), the central computer responsible for managing your engine and transmission. A faulty PCM can cripple your vehicle’s reliability and performance. This replacement PCM, part number 16263494, is the definitive solution to get your truck or van running like new again.
From the Diagnostic Bay
We had a 2000 Chevy Express 3500 work van come in that was a real head-scratcher. The owner said it would randomly stall at idle, but only when warm, and would always restart after a few minutes. There were no diagnostic trouble codes stored, and fuel pressure and spark were perfect. After hours of chasing wires, we finally connected a lab scope to the PCM’s injector driver circuits. We saw the signal drop out completely for a split second, just before the engine would die. It was a classic case of internal PCM failure due to heat soak. We installed a VIN-programmed module just like this one, performed the security relearn, and the van has been running flawlessly for the client ever since. Sometimes, the problem is hidden deep inside the brain of the vehicle.
Symptoms of a Failing 1999-2000 GMC 3500 PCM
A failing PCM can manifest in numerous ways, often mimicking other component failures. If you’re experiencing any of the following, your PCM could be the culprit:
- โ Illuminated Check Engine Light (CEL) with various communication or sensor codes.
- โ Engine stalling, stumbling, or running rough at idle.
- โ Noticeable decrease in fuel efficiency.
- โ Harsh, erratic, or delayed automatic transmission shifting.
- โ Complete no-start condition where the engine cranks but won’t fire.
- โ Failure to communicate with diagnostic scan tools.
- โ Intermittent issues that seem to have no logical cause.
The Plug-and-Program Solution
Don’t settle for a generic, unprogrammed module that requires an expensive trip to the dealership for flashing. Our process is designed to save you time and money. When you purchase this module, we will flash it with the latest official GM software updates specifically for your vehicle. All we need is your 17-digit Vehicle Identification Number (VIN). This ensures that the module communicates perfectly with your vehicle’s specific engine, transmission, and options package. It arrives at your door ready for installation, taking the guesswork out of the repair.
This module is a direct replacement for multiple part numbers, including 16263494, 16265035, 8162634940, 218-11787, and 21811787. It fits a wide range of GM trucks and vans from the late 1990s and early 2000s, making it a versatile and reliable choice for your repair. By providing a properly programmed 1999-2000 GMC 3500 PCM, we help you avoid the common pitfalls of module replacement and ensure a successful, long-lasting repair.
Frequently Asked Questions
How does the VIN programming process work?
After you place your order, simply provide us with your vehicle’s 17-digit VIN. Our technicians will use this number to access the official GM database and load the correct software and calibrations for your specific truck or van onto the module before shipping it.
Is any additional programming required after installation?
In most cases, you will need to perform a security relearn procedure (often called Passlock or VATS relearn). This procedure syncs the new PCM with your vehicle’s anti-theft system and can typically be done without special tools. A Crankshaft Variation Relearn (CASE relearn) may also be necessary, which requires a capable scan tool.
Will this fix my transmission shifting problems?
If the shifting issues are caused by the PCM, then yes. The PCM controls transmission line pressure and shift points based on data from various sensors. A faulty PCM can cause harsh shifts, delayed engagement, or slipping. This module, programmed to your VIN, will restore correct transmission logic.
Where is the PCM located on my vehicle?
The location varies slightly by model. On most GMC/Chevrolet pickups and SUVs of this era, it’s in the engine compartment, typically on the driver’s side fender or near the battery. On Express and Savana vans, it’s often located in the left rear of the engine compartment.
How do I confirm this is the right part for my vehicle?
The best way is to match the service number on your original module to one of the compatible part numbers listed (16263494, 16265035, etc.). You can also use the detailed fitment list on this page to verify by year, make, and model.