Is Your Chevy Sonic Running Rough? Let’s Get It Fixed.
You rely on your car every day, so when the check engine light glares at you from the dash, or the engine starts stalling, hesitating, or refusing to start at all, it’s more than just an inconvenience—it’s a major disruption. These are classic signs that the brain of your engine, the Engine Control Module (ECM), may have failed. Don’t let a faulty computer keep you sidelined. This is your direct-fit, reliable solution.
This isn’t just a replacement part; it’s a complete, ready-to-install fix. We take a genuine GM ECM (Part #12679199) and professionally program it with the latest, most stable software updates from GM, specifically matched to your vehicle’s unique VIN. This means no expensive trips to the dealership for programming, no special tools required. You get a module that’s truly plug-and-play.
Common Symptoms of a Failing 2012 Sonic ECM:
If you’re experiencing any of the following, a failing ECM is a likely culprit. In my 20+ years as a diagnostician, I’ve seen these modules cause some of the most frustrating and hard-to-diagnose issues. Replacing it often resolves problems that mechanics have chased for weeks.
- ✔ Persistent Check Engine Light (CEL) with various codes
- ✔ Engine stalling or shutting off while driving
- ✔ Rough or erratic idle
- ✔ Vehicle won’t start, but the battery and starter are good
- ✔ Noticeable decrease in fuel economy
- ✔ Hesitation or stumbling during acceleration
- ✔ Communication errors with diagnostic scan tools
Expert Pro Tip: Check Your Grounds Before You Replace!
Before you spend money on any ECM, do this simple check. On many GM vehicles like the Sonic and Cruze, a corroded or loose main engine-to-chassis ground strap can cause identical symptoms to a failed ECM. It can create electrical noise and voltage drops that confuse the computer. Locate the main ground strap (often a braided cable from the engine block to the frame rail), unbolt it, and clean both the terminal and the mounting surface with a wire brush until they are bright metal. This 10-minute check has saved countless customers in my shop from replacing a perfectly good module.
Plug-and-Play Installation: No Dealer Visit Required
We’ve made this process as simple as possible. Because we program the module to your VIN before shipping, you can install it yourself in your own driveway.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the ECM: On the 2012 Sonic, the ECM is typically found in the engine bay, often near the battery or firewall.
- Disconnect Connectors: Carefully unclip the wiring harness connectors from the old module. Inspect them for any corrosion or damage.
- Swap the Modules: Unbolt and remove the old ECM. Mount the new, pre-programmed module in its place.
- Reconnect & Secure: Firmly plug the wiring harnesses into the new ECM until they click. Reconnect your battery terminal.
- Start the Engine: Your vehicle is now ready to run with its new, properly configured ECM.
Guaranteed Compatibility for Your GM Vehicle
This ECM is a direct replacement for part number 12679199 and is also fully compatible with the following interchangeable part numbers: 12642927, 12636386, 12621466, and 12630789. It is designed to fit a wide range of GM models, including:
- CHEVROLET CRUZE: 2011-2012 (1.8L Engine)
- CHEVROLET AVEO: 2009-2011
- CHEVROLET SPARK: 2013
- PONTIAC WAVE: 2009-2010
- CHEVROLET TRAX: 2013-2014 (1.8L Engine)
- CHEVROLET SONIC: 2012 (1.8L Engine)
- PONTIAC G3: 2009-2010
IMPORTANT: After placing your order, please provide us with your vehicle’s 17-digit VIN. This is essential for us to program the module correctly for your specific car. Your order cannot be shipped without it.