Is Your GM Vehicle Running Rough, Stalling, or Showing a Check Engine Light?
A failing Engine Control Module (ECM), often called the engine computer, is the brain of your vehicle’s engine management system. When it begins to fail, it can cause a cascade of frustrating and seemingly unrelated problems. From poor fuel economy and rough idling to a complete no-start condition, a faulty ECM can leave you stranded and facing a costly diagnostic bill. If you’re experiencing erratic engine behavior, persistent diagnostic trouble codes (DTCs), or communication errors with your scan tool, it’s highly likely the ECM is the culprit.
This replacement Engine Control Module, part number 12674472, is the definitive solution to restore your vehicle’s performance and reliability. Unlike generic, off-the-shelf modules that require expensive dealership programming, this unit is professionally programmed specifically for your vehicle using your VIN. We install the latest, most stable software updates from General Motors, ensuring optimal engine performance, fuel efficiency, and emissions control right out of the box. This critical programming step ensures all the unique parameters and systems of your vehicle are correctly managed, providing a seamless and effective repair.
From the Diagnostic Bay
We had a 2017 Sierra 1500 towed in with a baffling no-start condition. The engine would crank but never fire. The owner had already replaced the battery, spark plugs, and even the fuel pump with no success. Our initial scan showed multiple communication loss codes with the ECM. After verifying power and ground to the module were solid, we suspected an internal failure. Instead of a generic replacement, we ordered a VIN-programmed unit. Once it arrived, we installed it, performed the mandatory vehicle theft deterrent relearn using our GM software, and the truck fired up on the first try. The pre-programming saved hours of diagnostic time and eliminated the need for a trip to the dealer, getting the customer back to work faster.
Common Symptoms of a Failing ECM
- ✔ Check Engine Light is illuminated with various, often inconsistent, trouble codes.
- ✔ Engine cranks but will not start.
- ✔ Stalling, stumbling, or hesitation during acceleration.
- ✔ Noticeable decrease in fuel economy.
- ✔ Rough or erratic idling.
- ✔ Transmission shifting issues or harsh engagement.
- ✔ Loss of communication with the OBD-II port, preventing diagnostics.
- ✔ Misfire codes that persist even after replacing coils and plugs.
Why Choose Our Programmed GM ECM?
Choosing the right replacement part is critical for a lasting repair. Our service is designed to provide a reliable, plug-and-play (post-relearn) solution. We handle the complex programming so you don’t have to. By providing us with your vehicle’s VIN during checkout, you receive a module that is loaded with the correct calibration files for your specific engine, transmission, and emissions equipment. This eliminates guesswork and compatibility issues, making the installation process as straightforward as possible for you or your mechanic. This module is a direct fit for a wide range of GM vehicles, including the Cadillac XTS, Escalade, Chevrolet Silverado, Tahoe, Suburban, and GMC Sierra, among others. Please verify your original part number against our cross-reference list (12692068, 12704476, 12686382, 12674052, 12674472, 12678815) to ensure perfect compatibility.
Important Installation Information
A Vehicle Theft Deterrent System (VTD) relearn is mandatory after installation. This is a security procedure that syncs the new ECM to your vehicle’s ignition key and Body Control Module. If this procedure is not performed, your vehicle will not start. This relearn must be done using a professional-grade scan tool with GM-specific software, such as GM’s TIS2Web or Techline Connect. Additionally, other procedures like a crankshaft position variation relearn or injector flow rate programming may be necessary depending on your specific vehicle. These procedures are the responsibility of the installer and are standard practice when replacing an engine computer.
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) allows us to load the exact GM-approved software and calibration files for your vehicle’s specific engine, transmission, and options. This ensures the ECM functions perfectly and avoids compatibility problems.
What is a theft deterrent relearn?
It’s a security procedure that pairs the new ECM to your vehicle’s anti-theft system. Without it, the system assumes the module is stolen and will disable the engine. This procedure requires a compatible professional scan tool and cannot be bypassed.
Can I install this myself?
While the physical installation is often straightforward (disconnecting the battery, unbolting the old unit, and plugging in the new one), the required post-installation electronic procedures, like the theft relearn, require specialized tools. We recommend professional installation by a qualified technician.
Is this part compatible with my vehicle?
This module fits a wide range of 2016-2018 GM trucks and cars. Please check the fitment list on this page and, most importantly, match your original part number to one of the compatible numbers listed: 12692068, 12704476, 12686382, 12674052, 12674472, or 12678815.
What if my vehicle has other issues?
This ECM will solve problems directly caused by a faulty module. However, it will not fix underlying mechanical or electrical issues, such as a bad sensor or wiring harness. Always ensure a proper diagnosis has been performed before ordering.