Restore Peak Performance to Your GM Vehicle
Is your Chevrolet Cruze, Sonic, or other compatible GM vehicle suffering from frustrating issues like a persistent check engine light, stalling, rough idling, or a complete no-start condition? These are classic signs of a failing Engine Control Module (ECM), the central computer of your vehicle. A faulty ECM can disrupt everything from fuel delivery and ignition timing to transmission shifting, leading to poor performance, reduced fuel economy, and failed emissions tests. Don’t let a bad module keep you off the road. This replacement ECM, part number 12643636, is the reliable, straightforward solution you need.
What sets this module apart is our professional programming service. Before we ship your part, we flash it with the latest official GM software updates, specifically calibrated to your vehicle’s unique Vehicle Identification Number (VIN). This means you receive a part that is truly ready for installation, eliminating the need for expensive dealership programming or specialized scan tools. It’s the most efficient way to get your car running correctly again.
Case Study: A Tricky Diagnosis
A 2014 Chevy Sonic with the 1.4L turbo came into my bay with a bizarre set of symptoms. The owner reported intermittent stalling at red lights and a check engine light that would come and go. My scan tool pulled a P0601 (Internal Control Module Memory Check Sum Error) and a U0100 (Lost Communication With ECM/PCM). While a loose ground or wiring issue can sometimes cause U-codes, the P0601 code is almost always a definitive sign of internal ECM failure. The module’s own self-check was failing. We replaced the original ECM with one of these VIN-programmed units. The installation took less than 30 minutes, and after a quick throttle body relearn, the car ran perfectly. The codes were cleared and never returned, solving a problem that had frustrated the owner for months.
Common Signs of a Failing ECM
- ✔ Check Engine Light is on, often with codes like P0601, P0606, or U0100.
- ✔ Engine stalls, misfires, or runs rough.
- ✔ Vehicle will not start, even with a good battery and starter.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ Automatic transmission shifts erratically or harshly.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Failure to pass state emissions inspections.
A Straightforward Guide to Installation
- ✔ Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- ✔ Locate the ECM: On most compatible vehicles like the Cruze or Sonic, the ECM is located in the engine bay, often near the battery or firewall. It’s a silver metal box with several large electrical connectors.
- ✔ Disconnect and Remove: Carefully unplug the wiring harness connectors. They have locking tabs that need to be released. Once disconnected, unbolt the old module from its mounting bracket.
- ✔ Install the New Module: Bolt the new, pre-programmed ECM into place. Firmly reconnect the wiring harnesses, ensuring each connector clicks securely into place.
- ✔ Final Steps: Reconnect the negative battery terminal. In some cases, a security or throttle relearn procedure may be necessary. This can typically be done without special tools by following instructions in your owner’s manual or a quick online search for your specific model. Start the vehicle and let it idle to confirm the repair.
Verified Vehicle Compatibility
This ECM is a direct replacement for part number 12643636 and interchanges with 12668866, 12668994, 12663405, 12670335, 22819494, and 12692200. It fits a wide range of GM vehicles. Please verify your part number or contact us with your VIN to ensure compatibility. Key models include:
CHEVROLET SONIC (2012-2016)
CHEVROLET TRAX (2013-2016)
CHEVROLET SPARK (2014-2015)
CHEVROLET VOLT (2011-2015)
CHEVROLET ELR (2014-2016)
CHEVROLET SILVERADO 2500/3500 (2012-2016 w/ 6.0L)
CHEVROLET SUBURBAN 3500 (2016)
CHEVROLET EXPRESS 2500/3500 VAN (2016 w/ 4.8L or 6.0L)
BUICK ENCORE (2013-2016)
GMC SIERRA 2500/3500 & DENALI (2012-2016 w/ 6.0L)
GMC SAVANA 2500/3500 VAN (2016 w/ 4.8L or 6.0L)
*Fitment depends on specific options. Providing your VIN is the best way to guarantee a perfect match.
Frequently Asked Questions
How does the VIN programming work?
How does the VIN programming work?
After you complete your purchase, simply send us a message with your 17-digit VIN. Our technicians will use this number to load the correct, most current GM software for your vehicle’s specific configuration onto the module before we ship it out.
Will I need to do anything else after installation?
While our programming handles the engine and transmission software, some GM vehicles require a simple security relearn procedure (often called VATS or Passlock) to sync the new ECM with your keys. This procedure can usually be done in your driveway and does not require a scan tool. Instructions are widely available online for your specific model.
Is this a new or used part?
This is a high-quality, tested, and guaranteed functional used component. Each module is thoroughly inspected and then programmed with fresh GM software to ensure it performs reliably, offering a cost-effective alternative to a brand-new dealership part.
How do I find my original part number?
Your original part number is printed on a sticker on the case of your current ECM. You can compare it to our list of compatible numbers. However, the easiest and most accurate method is to simply provide us with your VIN, and we will verify perfect compatibility for you.