Is Your Workhorse GMC 3500 Suddenly Unreliable?
If you’re dealing with frustrating issues like your 1998 or 1999 GMC 3500 stalling for no reason, refusing to start, or running rough with a persistent Check Engine Light, the problem often points directly to a failing Powertrain Control Module (PCM). As the electronic brain of your truck, when the PCM starts to go, it can create a host of confusing and intermittent problems that are tough to diagnose.
“A customer’s 1999 GMC 3500 came in last week with these exact symptoms. It was a fleet vehicle, and the driver reported it would die randomly at stoplights, then restart after a few minutes. We scanned it and found no communication with the PCM. After checking all the power and ground circuits to the module, we confirmed the PCM itself was failing internally, likely from years of heat soak under the hood. Replacing it with a correctly programmed unit had the truck back on the road reliably the same day.”
The Technician’s Diagnosis: Why These PCMs Fail
In my 20+ years in the shop, I’ve seen hundreds of these specific GM ‘black box’ PCMs. They are generally robust, but after two decades of service, failure is common. The main culprits are typically:
- โ Heat and Vibration: Located in the engine bay, these modules endure constant temperature swings and engine vibration. Over time, this can cause microscopic cracks in solder joints on the internal circuit board, leading to intermittent connections and unpredictable behavior.
- โ Component Aging: Internal electronic components like capacitors can degrade and fail after years of service, disrupting the precise voltage signals needed for the processor to function correctly.
- โ Voltage Spikes: A faulty alternator or a jump-start gone wrong can send a surge of voltage through the electrical system, damaging the sensitive circuits inside the PCM beyond repair.
The Solution: A Direct-Fit, VIN-Programmed PCM
Don’t let a faulty computer sideline your truck. This Powertrain Control Module is the reliable, straightforward solution to get your GMC 3500 running properly again. It’s not just a replacement part; it’s a comprehensive fix that eliminates the guesswork and extra expense of dealer programming.
- โ Programmed to Your Truck: We flash this module with the latest official GM software calibrations specific to your vehicle’s VIN. This ensures all systems, from the engine and transmission to the emissions equipment, function exactly as the factory intended.
- โ Plug & Play Installation: Because the module arrives pre-programmed, installation is simple. There’s no need to have the vehicle towed to a dealership or pay for expensive programming services. In most cases, you can do the job in your own driveway with basic hand tools.
- โ Resolves Common Issues: A replacement PCM is the definitive fix for a wide range of problems, including false sensor codes, harsh shifting, poor fuel economy, and no-start conditions caused by a failed computer.
- โ Guaranteed Compatibility: This module is a direct replacement for part numbers 16250279, 09366810, and 09355699. Please check the number on your original module to confirm a perfect match.
Crucial Information: We Need Your VIN
To ensure 100% correct functionality, we must program this module to your truck. After placing your order, please send us your 17-digit Vehicle Identification Number (VIN). We cannot ship your part until we have this information. This step is what makes the installation process so simple on your end and guarantees the part works correctly right out of the box.
Verified Fitment For a Wide Range of GM Vehicles:
While this is listed for the GMC 3500, this common PCM was used across many GM trucks, vans, and SUVs from this era. If your vehicle is on this list and your original module has a matching service number (like 16250279), this part is the correct fit for you. Common applications include the Chevy Silverado/GMC Sierra 1500/2500/3500, Tahoe/Yukon, Suburban, Astro/Safari, Express/Savana, and more.