Restore Peak Performance to Your Cadillac
Is your 2009-2010 Cadillac STS, or another compatible GM vehicle, suffering from perplexing electrical issues, a persistent check engine light, or poor engine performance? The Engine Control Module (ECM) is the central computer of your vehicle, orchestrating everything from fuel mixture and ignition timing to transmission shifts and emissions controls. When it begins to fail, it can cause a cascade of frustrating and difficult-to-diagnose problems. This genuine GM engine control module, part number 12630464, is the definitive solution to restore your vehicle’s factory performance and reliability.
Unlike a generic, off-the-shelf part, this ECM is delivered to you fully programmed to your specific vehicle. Upon purchase, you simply provide us with your Vehicle Identification Number (VIN), and our technicians will flash the module with the latest, most up-to-date software directly from General Motors. This critical step ensures that the ECM communicates flawlessly with all other modules in your vehicle, recognizing its specific engine, transmission, and factory options for a true plug-and-play installation.
From the Diagnostic Bay
We once had a 2009 Cadillac STS 4.6L in the shop that was driving its owner crazy. It had an intermittent stalling problem and a random misfire code that would jump between cylinders. The owner had already replaced spark plugs, ignition coils, and even the fuel pump to no avail. After hours of checking wiring diagrams and sensor data, we noticed the 5-volt reference signal from the ECM would occasionally dip. Under load and heat, the internal voltage regulator in the original module was failing. We installed a VIN-programmed ECM, performed the security relearn, and the car ran perfectly. It’s a classic example of how a failing module can mimic other, more common component failures.
Is Your Vehicle Exhibiting These Symptoms?
A failing ECM can manifest in numerous ways. If you’re experiencing any of the following, a faulty engine computer could be the culprit:
- ✔ Persistent Check Engine Light (CEL) that won’t clear or returns immediately.
- ✔ Unexplained loss of engine power or poor acceleration.
- ✔ A noticeable decrease in fuel economy.
- ✔ Rough idling, engine stumbling, or stalling.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Intermittent no-start or hard-starting conditions.
- ✔ Communication error codes (U-codes) when using a diagnostic scan tool.
- ✔ Misfire codes that persist after replacing plugs, coils, and injectors.
The Importance of a VIN-Programmed 2009-2010 STS ECM
Modern vehicles are complex networks of computers. The ECM must be correctly configured to work within this network. Our VIN-programming service is not an option—it’s a necessity for proper function. By flashing the module with your vehicle’s unique data, we ensure it correctly manages the anti-theft system (VATS/Passlock), emissions equipment, and engine/transmission parameters specific to your Cadillac STS. This eliminates the need for expensive dealership programming and allows for a straightforward installation process for you or your mechanic.
This module is a direct replacement for a wide range of GM vehicles and is interchangeable with the following service numbers: 12636659, 12639300, 1263605, 12628993, 12628911, 12625453, 12622175, 12630464, and 12678512. Please verify your vehicle’s fitment in the compatibility list to ensure this is the correct part for your application.
Frequently Asked Questions
Do I need to do any additional programming after I receive this ECM?
No. We flash the module with the latest GM software using the VIN you provide. In most cases, the only additional step is a simple security relearn procedure, which does not require any special tools.
What is a security relearn procedure?
It’s a sequence of key turns that syncs the new ECM with your vehicle’s anti-theft system. This allows the car to start. We can provide easy-to-follow instructions for this process.
Is this part difficult to install?
The physical installation is straightforward for anyone 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 on the 2009-2010 STS is typically on the driver’s side frame rail.
Where can I find my vehicle’s VIN?
Your 17-digit VIN can be found on the driver’s side of the dashboard (visible through the windshield), on the sticker in the driver’s side door jamb, or on your vehicle’s registration and insurance documents.
How can I be sure my old ECM is the problem?
While this part resolves all issues related to a faulty ECM, it’s crucial to have your vehicle properly diagnosed. Ensure that wiring, grounds, sensors, and other related components have been checked, as they can sometimes cause similar symptoms.
My original module has a different part number. Will this still work?
Yes. This ECM, part number 12630464, is the updated service replacement for several older part numbers, including 12636659, 12628993, and others listed in the description. As long as your vehicle model and year are on the compatibility list, this module will function correctly.