Restore Peak Performance to Your GM Truck or Van
As a technician with over two decades of experience under the hood, I’ve seen firsthand the frustration a failing Powertrain Control Module (PCM) can cause. It’s the brain of your vehicle, and when it starts to malfunction, you get a cascade of baffling problems: a check engine light that won’t go away, a truck that refuses to start, rough idling, or terrible fuel mileage. You’re not just buying a part; you’re buying a solution to get your reliable workhorse back on the road. This isn’t just a replacement; it’s a new lease on life for your engine and transmission.
This PCM is the definitive fix for your 1999-2000 Chevrolet 3500 PCM issues. We take the guesswork and hassle out of the equation. Before we ship it, our experts program the module with the latest GM-certified software, tailored specifically to your vehicle’s VIN. This means no expensive trips to the dealership for programming. It arrives at your door ready for a straightforward installation, allowing you to restore factory performance, shifting, and efficiency.
Case Study: The Ghost in the Machine
I remember a 2000 GMC Sierra that came into my shop with an issue that had stumped two other mechanics. The owner said it would randomly stall at red lights, but never threw a consistent code. We checked fuel pressure, sensors, and wiring harnesses—everything looked perfect. On a hunch, I monitored the live data stream from the PCM. I noticed the injector pulse width would erratically drop to zero just before a stall. The PCM was failing internally under specific thermal conditions, cutting fuel for a split second. We installed a VIN-programmed PCM just like this one, and the problem vanished instantly. It’s often the component you suspect last that’s been the culprit all along.
Is Your Truck’s Brain Failing? Common Symptoms
A faulty PCM can manifest in numerous ways. If your vehicle is experiencing any of the following, a failing module is a likely cause. Look out for Diagnostic Trouble Codes (DTCs) like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (PCM Processor Fault).
- âś” Check Engine Light is on with communication error codes.
- âś” Engine cranks but refuses to start.
- âś” Rough or unpredictable idling.
- âś” A significant, unexplained drop in fuel economy.
- âś” Harsh or erratic automatic transmission shifting.
- âś” The vehicle fails an emissions test.
- âś” Intermittent stalling or loss of power while driving.
Simple Swap: Your Installation Guide
Installing your new PCM is a job most DIYers can handle with basic tools. While specific locations vary slightly by model (e.g., under the hood on pickups, in the engine compartment on vans), the general process is consistent.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting work.
- Locate the PCM: On most trucks like the Silverado or Sierra, it’s on the driver’s side near the firewall or battery. On Express/Savana vans, it’s often in the LH rear of the engine compartment.
- Disconnect Connectors: Carefully unclip the wiring harness connectors from the old module. These have locking tabs, so be gentle to avoid damage.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Bolt your new, pre-programmed PCM into place and securely reconnect the wiring harnesses. Ensure they click into place.
- Reconnect Battery: Reattach the negative battery terminal.
- Perform Security Relearn: You may need to perform a simple key-cycle security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes. This allows the new PCM to recognize your vehicle’s anti-theft system.
Verified Fitment for Your GM Truck or Van
This module is a direct replacement for a wide range of GM vehicles. Please confirm your model and year below. This part is a direct replacement for part numbers: 16263494, 16265035, 8162634940, 218-11787, 21811787.
ASTRO 99-01 (4.3L)
BLAZER/JIMMY S-SERIES 98-00 (w/ build date opt ZN4 for 98)
BRAVADA 98-00 (w/ build date opt ZN4 for 98)
CHEVROLET/GMC 1500 PICKUP 99 (5.0L, 5.7L)
CHEVROLET/GMC 2500 PICKUP 99-00 (Gasoline)
CHEVROLET/GMC 3500 PICKUP 99-00 (Gasoline)
ENVOY 98-00 (w/ build date opt ZN4 for 98)
ESCALADE 99-00
EXPRESS/SAVANA 1500 VAN 99-02
EXPRESS/SAVANA 2500 VAN 99-02 (Gasoline)
EXPRESS/SAVANA 3500 VAN 99-02 (Gasoline)
ISUZU HOMBRE 98-00 (4.3L, w/ extended build date opt ZN4 for 98)
S10/S15/SONOMA 98-00 (4.3L, w/ build date opt ZN4 for 98)
SAFARI (GMC) 99-01
SIERRA/SILVERADO 1500 PICKUP 99-00 (4.3L V6)
SUBURBAN 1500/2500 99 (Gasoline)
TAHOE 99-00 (Classic Style for 00)
YUKON 99-00 (Denali for 00)
Do I need to do any programming myself?
Do I need to do any programming myself?
No. This is the biggest benefit of our service. We program the module to the exact VIN you provide before shipping. This makes the installation process as simple as possible, saving you a costly trip to a dealer or specialized shop.
How do I provide my VIN?
After you complete your purchase, you will need to send us your vehicle’s 17-digit VIN (Vehicle Identification Number). We cannot ship the module until we receive this information, as the programming is specific to your truck.
What is the security relearn procedure?
For many GM vehicles of this era, the Passlock anti-theft system needs to sync with the new PCM. This is a simple procedure you can do yourself. Typically, it involves turning the key to the ‘ON’ position (without starting the engine) for 10-15 minutes, then turning it off, and then starting the vehicle. We include simple instructions for this process.
Will this fix my specific problem?
While this 1999-2000 Chevrolet 3500 PCM is the solution for a wide range of electronic and drivability issues, proper diagnosis is key. If your vehicle shows classic PCM failure symptoms like a P0601 code, no-start conditions, or erratic behavior that can’t be traced to a sensor, this module is very likely the fix you need.
Is there a core charge?
There is no core charge for this module. You do not need to send your old, faulty part back to us.