Is Your GM Truck or Van Running Rough?
The Powertrain Control Module, or PCM, is the central computer of your vehicle’s engine and transmission. It manages everything from fuel injection and ignition timing to transmission shift points and emissions controls. When this critical component begins to fail in your 1999-2000 GMC 3500 Pickup or other compatible GM vehicle, it can cause a wide range of frustrating and potentially damaging issues. You might experience a sudden drop in fuel economy, unpredictable stalling, or a persistent Check Engine Light that won’t go away. Don’t let a faulty computer keep your reliable truck off the road.
From the Diagnostic Bay
We had a 2000 Chevy Express van come in with a complaint of intermittent harsh shifting and stalling at idle. The customer had already replaced the transmission fluid and filter with no improvement. A quick scan showed no communication with the PCM. Before condemning the module outright, we always check the fundamentals. We inspected the main PCM connector and found one of the pins had backed out slightly, causing a poor connection. After re-seating the pin and cleaning the contacts, the van ran perfectly. Always inspect connectors and grounds before replacing a module—it can save you time and money.
Symptoms of a Failing Powertrain Control Module
- ✔ Persistent Check Engine Light (CEL) on your dashboard.
- ✔ Engine stalling, stumbling, or misfiring for no apparent reason.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ A noticeable decrease in fuel efficiency.
- ✔ The vehicle fails to start, even with a good battery and starter.
- ✔ Failure to communicate with diagnostic scan tools.
- ✔ Inaccurate or erratic gauge readings.
The Plug-and-Play Solution: A Pre-Programmed 1999-2000 GMC 3500 PCM
Replacing a PCM isn’t as simple as swapping out a battery. The module must be programmed specifically to your vehicle’s Vehicle Identification Number (VIN). This process traditionally required a trip to the dealership and expensive specialty tools. We eliminate that hassle. This Powertrain Control Module is a direct-fit replacement for your original unit and arrives at your door fully programmed with the latest GM software updates for your specific vehicle. All we need is your VIN during the checkout process. This ensures that once installed, your vehicle will function exactly as the manufacturer intended, restoring lost power, efficiency, and reliability. This is the most effective way to get your truck back to peak operating condition without the dealership price tag.
This module is a reliable replacement for multiple OEM part numbers, including 16263494, 16265035, and 8162634940. It fits a wide range of Chevrolet and GMC trucks, vans, and SUVs from the late 1990s and early 2000s. Please verify your part number and consult the detailed fitment list to ensure this is the correct part for your vehicle. By choosing our pre-programmed 1999-2000 GMC 3500 PCM, you’re not just buying a part; you’re getting a complete, ready-to-install solution.
Frequently Asked Questions
How do I provide my vehicle’s VIN?
You can enter your 17-digit VIN in the notes section during checkout. If you forget, don’t worry! We will contact you via email after your purchase to request the necessary information before we program and ship your module.
Is this part difficult to install?
Installation is straightforward for someone with basic mechanical skills. The PCM is typically located in the engine bay. You will need to disconnect the vehicle’s battery, unplug the electrical connectors from the old module, unbolt it, and then install the new one in its place. Basic hand tools are usually all that is required.
What does ‘plug and play’ mean exactly?
‘Plug and play’ means the module arrives pre-programmed for your specific VIN and requires no further programming from a dealer. In some GM vehicles, a simple security relearn procedure (also known as a CASE relearn) may be necessary after installation. This procedure is easy to perform and we can provide instructions.
Will this fix my check engine light?
If the check engine light and associated symptoms are caused by a faulty PCM, this replacement module will solve the problem. However, it’s crucial to have your vehicle properly diagnosed to confirm the PCM is the root cause before ordering.
Do I need to send my old part back?
No, there is no core charge or requirement to return your old module for this part. You can recycle your old one locally.