Restore Peak Performance and Reliability to Your Vehicle
Is your vehicle suffering from frustrating, hard-to-diagnose issues like a persistent check engine light, erratic engine behavior, or a complete no-start condition? The Engine Control Module (ECM), the electronic brain of your vehicle, is often the root cause. After 20 years in the garage, I’ve seen firsthand how a failing ECM can mimic a dozen other problems, leading to wasted time and money on incorrect repairs. This replacement Engine Control Module, part number 12639300, is the definitive solution, arriving at your door fully programmed with the latest GM software updates specifically for your vehicle’s VIN.
Forget the expensive trip to the dealership and the hassle of coordinating programming. We handle the complex part for you. Simply provide your Vehicle Identification Number (VIN) during checkout, and our technicians will flash the module, ensuring it’s a true plug-and-play component. This process restores factory communication protocols and engine performance parameters, resolving the core electronic issues and getting you back on the road with confidence. This is the same reliable fix I would perform in my own service bay.
Case Study: The Phantom Misfire on a C6 ZR1
A customer brought in a beautiful 2009 Corvette ZR1 with an intermittent, high-RPM misfire that no one could solve. They had already replaced plugs, wires, and coils. Scans showed random misfire counts but no consistent codes. After checking fuel pressure and wiring integrity, my experience pointed toward the ECM. Under heavy load, the processor was likely faltering. We installed a VIN-programmed 2009 Corvette Engine Control Module just like this one. The installation took less than 30 minutes. On the test drive, the ZR1 pulled cleanly to redline with zero hesitation. The problem was solved—not with more hard parts, but by restoring the engine’s central command unit.
Is Your Vehicle Showing These Telltale Signs?
- ✔ Unexplained Check Engine Light with codes like P0601, P0606, or U0100.
- ✔ Engine cranks but refuses to start.
- ✔ Noticeable decrease in fuel economy.
- ✔ Rough idling, stalling, or hesitation during acceleration.
- ✔ Automatic transmission shifting erratically.
- ✔ Apparent loss of power and poor overall performance.
- ✔ Communication issues with diagnostic scan tools.
A Straightforward Guide to Installation
- ✔ Safety First: Disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent accidental reconnection.
- ✔ Locate the ECM: On a 2009 Corvette, the ECM is typically found in the right-hand side of the engine compartment. For other models, its location can vary (e.g., RH firewall, inside the air cleaner box).
- ✔ Disconnect Connectors: Carefully unclip the wiring harness connectors from the old module. These usually have a locking tab that needs to be released. Avoid pulling on the wires themselves.
- ✔ Remove Old Module: Unbolt the old ECM from its mounting bracket. Keep the mounting hardware as you will need it for the new unit.
- ✔ Install New Module: Mount your new, pre-programmed 2009 Corvette Engine Control Module using the original hardware. Ensure it is secure.
- ✔ Reconnect and Secure: Firmly plug the wiring harnesses into the new ECM. You should hear or feel a click as they lock into place.
- ✔ Final Steps: Reconnect the negative battery terminal. A security relearn procedure may be required, which typically involves turning the key to the ‘ON’ position for 10-15 minutes. Start the engine and let it idle to confirm proper operation.
Verified Vehicle Compatibility
This module is a direct replacement for a wide range of General Motors vehicles. Please verify your specific model and engine option below. This unit is interchangeable with service numbers: 12636659, 12639300, 1263605, 12628993, 12628911, 12625453, 12622175, 12630464, and 12678512.
CADILLAC DTS 2009-2011
CADILLAC SRX 2009 (4.6L)
CADILLAC STS 2009 (4.4L, 4.6L), 2010 (4.6L)
CADILLAC XLR 2009
CHEVROLET COLORADO 2009-2012 (2.9L, 3.7L)
CHEVROLET CORVETTE 2009 (ZR1)
CHEVROLET TRAILBLAZER 2009 (6.0L)
GMC CANYON 2009-2012 (2.9L, 3.7L)
GMC ENVOY 2009 (5.3L)
HUMMER H3 2009-2010 (3.7L)
BUICK LUCERNE 2009-2011 (4.6L)
SAAB 9-7X 2009
Frequently Asked Questions
Do I need to do any programming myself?
No. This module comes fully programmed to your vehicle’s specific VIN. It is ready for installation right out of the box, with no additional programming required.
Where do I provide my VIN?
Please enter your 17-digit Vehicle Identification Number (VIN) in the designated field during the checkout process. We cannot ship the module without it.
Is this a brand new part?
This is a high-quality, tested component guaranteed to function to OEM specifications. It is loaded with the newest software available from GM for your vehicle.
What if my original part number isn’t 12639300?
This module is a direct replacement for several service numbers, including 12636659, 12628993, and others listed in the description. As long as your vehicle is on the compatibility list, this part will work.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the ECM (common codes P0601-P0606), then yes, this part is the correct fix. It’s crucial to have a proper diagnosis to ensure the ECM is the faulty component.