Is Your GM Truck or Van Acting Up?
If you’re dealing with a 1999-2000 Chevrolet 3500, or a similar GM vehicle from that era, you know it’s a workhorse. But when the brain of the operationโthe Powertrain Control Module (PCM)โstarts to fail, that reliable truck can become a real headache. You might be experiencing a frustrating mix of issues that seem to come out of nowhere.
Over my 20+ years in the shop, I’ve seen these exact modules cause some of the most confusing diagnostic problems. The symptoms aren’t always a simple ‘Check Engine’ light. They can be intermittent and maddening.
Common Symptoms of a Failing GM PCM
A faulty PCM can manifest in numerous ways. Before you start throwing expensive sensors at the problem, see if any of these sound familiar:
- โ Unexplained Check Engine Light (CEL) that won’t clear, or codes like P0601 or P0606 (Internal Module Failure).
- โ Harsh or erratic automatic transmission shifting.
- โ The engine cranks but refuses to start.
- โ Stalling, rough idling, or poor fuel economy.
- โ The anti-theft or security light stays on, preventing the engine from running.
- โ Communication errors when you plug in a scan tool.
A Technician’s Real-World Experience
“A customer’s 1999 Chevrolet 2500 with the 5.7L Vortec came in last week with these exact symptoms. It would randomly stall at red lights and sometimes wouldn’t restart for 10-15 minutes. The owner had already replaced the fuel pump and ignition coil with no luck. When we hooked up our professional scanner, we found a P0601 ‘Internal Control Module Memory Check Sum Error’ code. This code is a dead giveaway. After years of heat cycles and vibration under the hood, the internal processors and capacitors on the original PCM had failed. We installed one of our VIN-programmed modules, performed the quick security relearn, and the truck has been running perfectly ever since. It’s a fix I’ve performed hundreds of times on these GM platforms.”
The Solution: A Reliable, Programmed Replacement
This isn’t just a part in a box. This is a complete solution. We are offering a replacement Powertrain Control Module that is professionally programmed to your vehicle’s specific Vehicle Identification Number (VIN) before it ships. This is the most critical step in the process.
Why is VIN programming so important?
- โ Plug & Play Ready: Your VIN contains all the specific information for your truck’s optionsโengine size, transmission type, gear ratios, and emissions equipment. Our programming ensures the PCM works with these components seamlessly.
- โ Security System Compatibility: GM’s VATS or Passlock anti-theft systems are tied to the PCM. A non-programmed module will result in a no-start condition. Our service gets you past that hurdle.
- โ Latest GM Software: We flash the module with the newest available GM calibrations. This can often resolve factory bugs, improve transmission shift points, and enhance overall drivability compared to the original software.
- โ No Dealer Visit Needed: You avoid the hassle and high cost of having a dealership program a new module for you. This saves you significant time and money.
Guaranteed Compatibility
This module is a direct replacement for several part numbers. To ensure a perfect match, please verify that your original module has one of the following numbers printed on its label:
- โ 16263494
- โ 16265035
- โ 8162634940
- โ 218-11787
- โ 21811787
After you complete your purchase, simply send us a message with your vehicle’s 17-digit VIN. Our technicians will handle the programming, and your module will ship out ready for installation. In most cases, a simple 10-minute security relearn procedure (instructions included) is all that’s needed to get your truck back on the road.