Get Your Vehicle Back on the Road, Fast.
Is your vehicle plagued by a persistent check engine light, erratic stalling, poor fuel economy, or a frustrating no-start condition? These are classic signs of a failing Engine Control Module (ECM), the central computer of your vehicle. Don’t let a faulty computer keep you sidelined. This direct-fit, professionally programmed 12639300 ECM is the definitive solution to restore your vehicle’s performance, reliability, and drivability without an expensive trip to the dealership.
We take the guesswork out of the repair. Simply provide us with your vehicle’s VIN during checkout, and our technicians will flash this module with the very latest GM factory software specific to your car or truck. It arrives at your door ready for a straightforward installation, ensuring all components in your vehicle communicate perfectly, just as the manufacturer intended.
Common Symptoms of a Failing ECM & Your Direct Solution
If you’re experiencing any of the following issues, a faulty engine computer is the likely culprit. This module is designed to resolve them:
- Persistent Check Engine Light (CEL) with codes like P0601, P0603, or P0606
- Unexplained engine stalling or hesitation
- Engine misfires or rough idling
- Noticeable decrease in fuel efficiency
- Erratic automatic transmission shifting
- Intermittent or complete no-start situations
- Communication errors with diagnostic scan tools
Installing this pre-flashed 12639300 ECM is the most reliable way to correct these complex electronic issues and restore the precise engine management your vehicle needs.
Features & Benefits
- ✔ VIN-Specific Programming: We flash the module to your exact VIN, ensuring 100% compatibility with your vehicle’s specific options and security systems for a hassle-free installation.
- ✔ Latest GM Software Updates: Your ECM arrives with the most current software from General Motors, often correcting factory bugs and improving overall performance and efficiency.
- ✔ Plug-and-Play Design: Simply install the module and perform the straightforward security relearn procedure (instructions available). No dealership visit required.
- ✔ Broad Compatibility: This unit is a direct replacement for a wide range of service numbers, including 12636659, 12639300, 1263605, 12628993, and more.
- ✔ Restored Engine Performance: A properly functioning ECM ensures optimal fuel delivery, ignition timing, and emissions control, bringing back the smooth power you expect.
- ✔ Peace of Mind Protection: This unit is backed by our one-year replacement warranty, giving you confidence in your purchase.
Expert Insight: The Critical Role of VIN Programming
Why is VIN-specific programming so important? In modern vehicles, the ECM doesn’t work alone. It’s in constant communication with the Transmission Control Module (TCM), Body Control Module (BCM), anti-lock brake system, and more. A generic, non-programmed computer can’t speak their language. This leads to a cascade of new error codes and system malfunctions. Our process ensures your new Programmed 12639300 ECM integrates seamlessly into this network, functioning as a perfect digital citizen within your vehicle’s ecosystem and preventing future electronic headaches.
Frequently Asked Questions
Do I need to do any additional programming or flashing?
No. This ECM arrives fully programmed to your vehicle’s VIN with the latest GM software. In most cases, you will only need to perform a simple security relearn procedure, which can typically be done in your driveway without any special tools. This procedure pairs the new ECM to your existing keys.
Where do I provide my vehicle’s VIN?
You can enter your 17-digit Vehicle Identification Number (VIN) during the checkout process. If you miss it, you can also reply to your order confirmation email with the VIN, and we will match it to your order.
My original part number is different. Will this still work?
Yes. This module is a direct replacement for multiple GM service numbers. As long as your vehicle is listed in the compatibility chart and your original part number is one of the following, this ECM will work perfectly: 12636659, 12639300, 1263605, 12628993, 12628911, 12625453, 12622175, 12630464, or 12678512.
How can I be sure my old ECM is the problem?
The symptoms listed above are strong indicators of ECM failure. Common diagnostic trouble codes (DTCs) pointing to a faulty computer include P0601 through P0606. However, we always recommend having a qualified mechanic perform a full diagnostic to rule out other potential issues like wiring or sensor faults before ordering.
Is this part difficult to install?
The physical installation is typically straightforward for someone with basic mechanical skills. It involves disconnecting the battery, unplugging the electrical connectors, and unbolting the old module to swap in the new one. The location varies by vehicle (e.g., LH engine bay, RH firewall), so we recommend consulting a repair manual for your specific model.