Restore Your GM Van or Truck’s Reliability
Is your 1999-2002 Chevy Express 1500 or another compatible GM vehicle acting up? Stalling, shifting erratically, or showing a persistent Check Engine Light can be incredibly frustrating, especially when your vehicle is your livelihood. As a technician with over two decades of experience, I’ve seen countless vehicles sidelined by a faulty Powertrain Control Module (PCM). This isn’t just a part; it’s the brain of your engine and transmission, and when it fails, it can cause a cascade of confusing problems. This replacement PCM, part number 16263494, is the dependable solution to get your vehicle running right again.
The biggest headache with replacing a PCM has always been the programming. A blank module from the parts store means a tow to the dealership and a hefty bill for flashing. We eliminate that entire process. When you order from us, we flash the module with the latest GM software updates specifically for your vehicle’s VIN. This means it arrives at your door ready for installation. You get a reliable part that restores original performance and efficiency without the dealership hassle.
Is Your GM Truck or Van Showing These Signs?
A failing PCM can manifest in various ways. If you’re experiencing any of the following, a faulty engine computer could be the culprit. I’ve personally diagnosed these symptoms hundreds of times in the shop.
- ✔ Engine stalling or randomly shutting off
- ✔ No-start condition where the engine cranks but won’t fire
- ✔ Harsh or erratic automatic transmission shifting
- ✔ A persistent Check Engine Light with codes like P0601, P0604, or P0605
- ✔ Poor fuel economy and engine performance
- ✔ Failure to communicate with a diagnostic scan tool
- ✔ Issues with the anti-theft system (Passlock/VATS)
Case Study: A Tricky Diagnosis
I remember a 2001 GMC Savana 2500 that came into my bay. The owner, a plumber, was at his wit’s end. The van would randomly stall in traffic, but after a few minutes, it would start back up. He had already replaced the fuel pump and crank sensor based on another shop’s advice, with no luck. After hooking up my scanner and monitoring live data, I noticed the 5-volt reference signal would drop out intermittently just before a stall—a classic sign of an internal PCM failure. We installed one of these VIN-programmed modules, performed the security relearn, and the van ran perfectly. It’s a textbook example of how a faulty PCM can mimic other component failures, making a reliable replacement essential for an accurate repair.
A Straightforward Guide to Installation
For the confident DIYer or professional mechanic, installing this 1999-2002 Express 1500 PCM is a manageable job. For the Express/Savana vans, the module is typically located in the engine compartment on the driver’s side.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On most vans and trucks covered, find the module in the engine bay, often near the battery or firewall. It will have several large multi-pin connectors.
- Disconnect the Connectors: Carefully unlatch and remove all electrical connectors from the old PCM. These connectors often have locking tabs that need to be released. Avoid forcing them.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed PCM securely onto the bracket.
- Reconnect Everything: Firmly plug all electrical connectors into the new module until they click into place. Reconnect the negative battery terminal.
- Perform Security Relearn: Most of these GM vehicles require a security relearn procedure to sync the new PCM with your keys. This can typically be done without a scan tool by cycling the key. A common method is: try to start the engine (it won’t start), leave the key in the ‘ON’ position for 10-15 minutes until the security light goes out, turn the key off, and repeat two more times. After the third cycle, the vehicle should start.
Verified Vehicle Compatibility
This module is a direct replacement for part number 16263494 and is compatible with other numbers including 16265035, 8162634940, 218-11787, and 21811787. Please verify your part number or contact us with your VIN to ensure compatibility. This unit fits a wide range of GM vehicles, including:
- Chevrolet Express & GMC Savana Vans (1500, 2500, 3500) – 1999-2002
- Chevrolet & GMC Pickups (1500, 2500, 3500) – 1999-2000
- Chevrolet Silverado & GMC Sierra 1500 (V6) – 1999-2000
- Chevrolet Astro & GMC Safari Vans – 1999-2001
- Chevrolet S10, GMC Sonoma, Isuzu Hombre (4.3L) – 1998-2000
- Chevrolet Blazer, GMC Jimmy, Oldsmobile Bravada, GMC Envoy – 1998-2000
- Chevrolet Tahoe, GMC Yukon, Cadillac Escalade – 1999-2000
- Chevrolet Suburban (1500 & 2500) – 1999
Note: This is a partial list. Always confirm fitment by the part number on your original module.
Do I need to do anything after I buy this?
Do I need to do anything after I buy this?
Yes. After you complete your purchase, you MUST send us your vehicle’s 17-digit VIN. We cannot ship your order until we have your VIN, as we use it to program the module with the correct GM software and updates for your specific vehicle.
Is this a plug-and-play part?
Because we program it to your VIN, it is as close to plug-and-play as possible. However, as noted in the installation guide, you will likely need to perform a security relearn procedure, which syncs the module to your vehicle’s anti-theft system. This procedure typically does not require special tools.
Will this fix my transmission shifting problems?
The PCM controls both engine and transmission functions. If your shifting problems are caused by a faulty computer, this module is the correct fix. It can resolve issues like harsh shifting, delayed engagement, and incorrect shift points that are electronically controlled.
How do I find my original part number?
Your original part number is printed on a sticker on the Powertrain Control Module itself. You will need to locate the module on your vehicle to read the sticker. For a 1999-2002 Express 1500 PCM, it is usually in the engine compartment on the driver’s side.