Restore Peak Performance to Your GM Vehicle
Is your Corvette, Silverado, or CTS suddenly running rough, refusing to start, or flashing a persistent Check Engine Light? A failing Engine Control Module (ECM) is often the culprit. As the central computer of your vehicle, the ECM governs everything from fuel injection and ignition timing to transmission shifting and emissions control. When it falters, the symptoms can be frustrating and widespread. In my 20 years of experience under the hood, I’ve seen how a faulty ECM can sideline even the most well-maintained vehicles, turning a reliable daily driver or a high-performance sports car into a source of constant headaches.
This isn’t just a replacement part; it’s a complete, ready-to-install solution. We offer a genuine GM Engine Control Module, part number 12662034, that arrives at your door pre-programmed with the very latest GM software updates. All we need is your vehicle’s VIN at checkout. This critical step ensures the module is perfectly matched to your vehicle’s specific configuration, eliminating the need for an expensive trip to the dealership for programming. For a DIY enthusiast or a professional mechanic, this means less downtime and a more efficient, reliable repair.
From the Diagnostic Bay: The Ghost in the Machine
A customer brought in his 2015 Sierra 1500 with a perplexing issue: it would randomly stall at stoplights and occasionally refuse to start, but there were no consistent trouble codes—just a few random communication errors (U0100) that would come and go. We checked the battery, grounds, and fuel pump, all of which were fine. After hours of diagnostics, we noticed the 5-volt reference signal from the ECM would momentarily drop out. This tiny fluctuation was enough to cause chaos. We installed one of these pre-programmed ECMs, and the truck has run flawlessly ever since. It’s a classic example of how a failing ECM can create ghost-like problems that are nearly impossible to trace without replacing the core component.
Is Your GM Vehicle Showing These Symptoms?
A failing ECM can manifest in many ways. If you’re experiencing any of the following, this module is the likely solution. I’ve personally traced these issues back to a faulty ECM hundreds of times in my shop.
- ✔ Unexplained Check Engine Light illumination
- ✔ Engine stalling or misfiring for no apparent reason
- ✔ Vehicle refuses to start, even with a good battery and starter
- ✔ Noticeable decrease in fuel economy
- ✔ Harsh or erratic automatic transmission shifting
- ✔ Communication-related Diagnostic Trouble Codes (DTCs) like U0100, U0101
- ✔ Internal module failure codes, such as P0601, P0606, or P062B
A Straightforward Guide to Installation
Replacing your ECM is a manageable job for a confident DIYer. By sending you a pre-programmed module, we’ve handled the most complex part. Follow these general steps to get your vehicle back in top form.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before beginning any electrical work.
- Locate the ECM: On a 2014-2016 Corvette, the ECM is found on the right-hand side, under the cowl panel near the dash. On trucks like the Silverado or Sierra, it’s typically in the front left of the engine compartment. Consult a service manual for your specific model if you’re unsure.
- Disconnect Connectors: Carefully release the locking tabs on the electrical harness connectors and pull them straight out from the module. Never force them. Inspect the connectors for any corrosion or damage.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep the mounting hardware, as you will need it for the new module.
- Install the New Module: Mount your new, pre-programmed ECM in place and secure it with the original hardware.
- Reconnect Everything: Firmly plug the electrical connectors back into the new ECM until they click into place. Reconnect the negative battery terminal.
- Final Steps: Depending on your vehicle, a security relearn procedure or crankshaft position variation relearn may be required. This can often be done without special tools (e.g., by cycling the key) or with a capable scan tool. Your vehicle is now ready to start.
Verified Compatibility Across the GM Lineup
While this is a direct-fit 2014-2016 Corvette ECM, this versatile module is also the correct service part for a wide range of popular GM cars, trucks, and SUVs. Please verify your part number or match your vehicle from the list below. This module is a direct replacement for part numbers: 12692067, 12676230, 12656993, 12672537, 12673195, 12663391, 12672963, and 12669318.
- ATS (2014-2016)
- Camaro (2016)
- Canyon / Colorado (2015-2016)
- Corvette (2014-2016)
- CTS (2014-2016)
- Escalade / Escalade ESV (2015-2016)
- Sierra 1500 / Silverado 1500 (2014-2016)
- Suburban / Tahoe (2015-2016)
- XTS (2014-2016)
- Yukon / Yukon XL (2015-2016)
Frequently Asked Questions
Do I really need to provide my VIN?
Yes, providing your VIN is essential. We use it to load the precise, factory-correct software and calibrations for your specific vehicle. This ensures seamless integration and proper function of all vehicle systems, saving you from a costly programming fee at a dealership.
Is this a simple plug-and-play installation?
For most vehicles, yes. Because we program it to your VIN, it’s designed to be a direct replacement. Some GM vehicles may require a simple security or crankshaft variation relearn procedure after installation, which can often be done with a basic key-cycling procedure or a standard professional scan tool.
Will this fix my specific problem?
This module corrects issues directly caused by a failing ECM, such as internal processor faults (P06xx codes), no-start conditions, and erratic engine behavior. While it solves the most common problems, always ensure your vehicle’s issues have been properly diagnosed by you or a qualified technician first.
Are there any other parts I need to buy?
No additional parts are required for the installation of the module itself. You will reuse your existing mounting bolts and brackets.
What if my original part number is not 12662034?
No problem. This ECM is a superseding part that replaces numerous older part numbers. Please check the compatible part number list in our description (e.g., 12692067, 12676230, etc.). If your number is on that list, this module is the correct, updated replacement for your vehicle.