Restore Peak Performance to Your Workhorse Van
As a technician with over two decades of experience, I’ve seen firsthand how a failing Powertrain Control Module (PCM) can turn a reliable work van into a source of constant frustration. If your 1999-2002 GMC Savana 3500 is suffering from strange electrical issues, poor fuel mileage, or a persistent Check Engine light, the problem often traces back to this central component. The PCM is the brain of your vehicle, managing everything from fuel injection and ignition timing to transmission shifting. When it starts to fail, the symptoms can be confusing and lead to expensive, incorrect repairs.
This isn’t just a replacement part; it’s a complete solution. We take a quality, tested PCM and flash it with the latest official GM software updates, specifically programmed to your vehicle’s unique Vehicle Identification Number (VIN). This means it arrives at your door ready for installation, with no need for a costly trip to the dealership for programming. You get a reliable fix that restores factory performance and smooths out those frustrating drivability problems. It’s the most direct path to getting your van back on the road and working as hard as you do.
From the Diagnostic Bay: The Phantom No-Start
A local delivery business brought in their Savana 3500. The driver complained of random no-start conditions—it would be fine for days, then refuse to crank. We checked the battery, starter, and ignition switch, all of which tested good. There were no consistent trouble codes, just a history of communication errors. After spending hours chasing wires, I suspected the PCM. On these vans, heat and vibration can cause microscopic cracks in the PCM’s circuit board over time, leading to intermittent failures. We installed one of our pre-programmed modules, and the problem vanished instantly. The owner was thrilled to have his most reliable van back in service without losing another day of business to guesswork.
Is Your Van Exhibiting These Telltale Signs?
A faulty PCM can manifest in numerous ways. If you’re experiencing any of the following, this module is the likely solution:
- ✔ Check Engine Light is on with codes like P0601, P0602, or P0605 (Internal Control Module Memory/Processor Error).
- ✔ The engine cranks but refuses to start.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ A noticeable drop in fuel economy.
- ✔ The vehicle stalls unexpectedly, either while driving or at idle.
- ✔ Failure to communicate with a diagnostic scan tool.
- ✔ Failed emissions testing.
A Straightforward Guide to Installation
Installing your new PCM is a manageable job for a DIYer with basic tools. Following these steps will ensure a smooth process:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the Module: On most Savana and Express vans, the PCM is located in the engine compartment, on the left-hand (driver’s) side, near the rear. It’s a silver metal box with several large electrical connectors.
- Disconnect the Connectors: Carefully unlatch and remove all electrical harness connectors from the old PCM. They often have locking tabs that need to be released. Avoid pulling on the wires themselves.
- Remove the Old PCM: Unbolt the mounting bracket holding the old module in place and remove it from the vehicle.
- Install the New PCM: Mount your new, pre-programmed PCM in the same location and secure it with the original bolts.
- Reconnect Everything: Firmly plug all the electrical connectors into the new module until they click into place. Reconnect the negative battery terminal.
- Security Relearn Procedure: In many cases, you may need to perform a simple security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. This allows the vehicle’s anti-theft system to recognize the new PCM.
Verified to Fit These GM Trucks & Vans
This module is a direct replacement for part numbers 16263494, 16265035, and 8162634940. It is guaranteed to fit the following vehicles (please match your part number or contact us with your VIN to confirm):
CHEVROLET EXPRESS & GMC SAVANA VANS 1500/2500/3500 (1999-2002)
CHEVROLET ASTRO & GMC SAFARI (1999-2001)
CHEVROLET S10/BLAZER & GMC SONOMA/JIMMY (1998-2000)
CHEVROLET TAHOE & GMC YUKON (1999-2000)
CADILLAC ESCALADE (1999-2000)
OLDSMOBILE BRAVADA & GMC ENVOY (1998-2000)
ISUZU HOMBRE (1998-2000)
…and more. Please verify your specific model and part ID in the full list or with your VIN.
Frequently Asked Questions
Frequently Asked Questions
How does the VIN programming work?
After you place your order, you will provide us with your 17-digit VIN. We use this number to access the latest GM software for your specific vehicle configuration and flash it onto the module before shipping. This ensures it works correctly right out of the box.
Is this a plug-and-play part?
Yes, for over 95% of vehicles. Because it arrives pre-programmed to your VIN, you simply install it. Some vehicles may require a simple, key-on/key-off security relearn procedure, which does not require any special tools.
Will this fix my specific problem?
This module corrects issues directly caused by a failing PCM, such as internal processor faults (P0601), communication errors, and erratic engine/transmission behavior. While it solves many common problems, you should ensure your vehicle’s issues are not caused by other components like bad sensors or wiring.
Do I need to send my old PCM back?
No core charge or return is required for this part. You can keep or responsibly dispose of your old module.
What if my original part number isn’t listed?
The compatible part numbers are 16263494, 16265035, 8162634940, and 218-11787. If your number is different, please contact us with your VIN. We can verify compatibility to ensure you get the right part the first time.