Get Your Workhorse Running Right Again
Is your trusty Chevy, GMC, or Cadillac truck or van suddenly running rough, refusing to start, or throwing confusing check engine lights? A failing Powertrain Control Module (PCM) is often the culprit behind these frustrating and hard-to-diagnose issues. This isn’t just an inconvenience; it’s downtime that costs you time and money. This replacement PCM is the reliable, straightforward solution to restore your vehicle’s performance and get you back on the road with confidence.
Common Symptoms & Your Solution
If you’re experiencing any of the following, a faulty engine computer is the likely cause. This pre-programmed unit is designed to be the definitive fix for:
- Harsh or erratic automatic transmission shifting
- Engine stalling, stumbling, or rough idling
- Complete no-start condition with power to all other accessories
- Poor fuel economy and loss of power
- Check Engine Light with communication-related Diagnostic Trouble Codes (DTCs) like P0601, P0602, P0605, or P0606
- Intermittent issues that seem to have no other logical cause
Instead of struggling with a problematic original computer, you can solve the problem at its source. We flash this module with the latest GM software updates using your vehicle’s unique VIN, ensuring it’s ready for installation upon arrival.
Features & Benefits
- ✔ Plug & Play Ready: This PCM comes pre-programmed to your vehicle’s specific VIN. This crucial step ensures compatibility and helps avoid a costly trip to the dealership for programming.
- ✔ Updated GM Software: We load the newest available software from General Motors, which can resolve factory bugs, improve transmission shift points, and enhance overall engine performance.
- ✔ Direct-Fit Replacement: Guaranteed to fit and function for all part numbers listed, including 09355699, 16266645, 9355699, 16250279, 16258815, 09366810, and 9366810.
- ✔ Cost-Effective Repair: Get your truck, van, or SUV back in service without the high cost and hassle of sourcing a new computer from a dealer.
- ✔ Peace of Mind: This unit is backed by our one-year replacement warranty.
Expert Insight: The Brain of Your Drivetrain
As a technician, I’ve seen countless late-90s GM trucks and vans with well over 200,000 miles still running strong. Their engines and transmissions are legendary for their durability. However, the 20+ year old electronics are often the first major failure point. Heat cycles, vibration, and time can cause internal connections in the PCM to fail, leading to bizarre symptoms that can mimic a bad sensor or fuel pump. Replacing the PCM with a properly programmed unit like this 1999 Chevrolet 2500 PCM 16266645 is often the key to keeping these incredible vehicles reliable for years to come.
Frequently Asked Questions
What does ‘programmed to my VIN’ actually mean?
It means we use your 17-digit Vehicle Identification Number (VIN) to load the exact software and calibrations your specific vehicle needs. This includes information about your engine size, transmission type, and other factory options. This makes the installation process much smoother and is essential for proper vehicle operation.
How do I provide my VIN after purchase?
After you complete your purchase, you will receive instructions on how to send us your vehicle’s VIN. We cannot ship your part until we receive this information, as the programming is a required step.
Is this part difficult to install?
For someone with basic mechanical skills, replacing a PCM is typically straightforward. It’s usually located in the engine bay, held in by a few bolts and connected by electrical harnesses. Always disconnect the battery before starting. The most critical part is ensuring the connectors are clean and seat firmly.
Will I need to do anything after installing this PCM?
In many cases for these specific GM vehicles, you may need to perform a security relearn procedure (often called Passlock or Passkey) to allow the vehicle to start. On some models, a Crankshaft Variation Relearn (CASE Relearn) may also be needed with a capable scan tool to clear a specific check engine code. These procedures are standard for this type of repair.
How can I be sure this fits my vehicle?
Please check the comprehensive fitment list on this page. The most important step is to match one of the compatible service numbers (like 16266645 or 09355699) with the number on your original computer’s sticker. This ensures you are ordering the correct hardware for your 1999 Chevrolet 2500 PCM 16266645 replacement.