Is Your 2017 GM Vehicle Acting Up? It Could Be The ECM.
The Engine Control Module (ECM), often called the engine computer, is the electronic brain of your vehicle. It manages everything from fuel injection and ignition timing to transmission shifting and emissions control. When it starts to fail, it can cause a cascade of confusing and frustrating problems that can be difficult to diagnose. If your 2017 Buick Verano, Chevy Traverse, Cadillac XTS, or another compatible GM model is experiencing erratic behavior, a faulty ECM is a common culprit. This replacement ECM, part number 12666070, is the definitive solution to restore your vehicle’s performance, reliability, and efficiency.
We had a 2017 Chevy Equinox come into the shop with a complaint that stumped two other mechanics. The car would randomly stall at stoplights, had a persistent Check Engine Light with a slew of communication error codes (U-codes), and the transmission would sometimes shift harshly. The owner had already replaced the throttle body and a few sensors with no luck. After hooking up our professional scan tool and monitoring the live data stream, we noticed the ECM’s voltage readings were fluctuating erratically. All other power and ground tests to the module were solid. We suspected an internal failure in the original computer. Instead of sending the customer to the dealership for a costly replacement and programming session, we sourced this exact pre-programmed module. After a straightforward installation and performing the security relearn procedure, all the communication codes vanished, the engine ran smoothly, and the stalling issue was completely resolved. It’s a powerful reminder that sometimes the most complex-seeming issues have a direct, component-level solution.
Common Symptoms of a Failing Engine Computer
A failing ECM can manifest in many ways. If you’re noticing any of the following issues, it’s a strong indicator that your engine computer may need replacement:
- ✔ Check Engine Light: The most obvious sign. The light may be on constantly or illuminate intermittently. Codes related to module communication, sensor circuits, or processor faults often point directly to the ECM.
- ✔ Engine Stalling or Misfiring: The engine may stall for no apparent reason, either while driving or at idle. You might also experience rough idling or noticeable engine misfires.
- ✔ Poor Performance & Fuel Economy: A faulty ECM can’t properly calculate the air-fuel mixture, leading to a significant drop in power, acceleration, and miles per gallon (MPG).
- ✔ Starting Problems: The vehicle may crank but refuse to start, or it may not crank at all. This can happen if the ECM isn’t properly controlling the fuel pump or ignition system.
- ✔ Automatic Transmission Issues: In modern vehicles, the ECM works with the Transmission Control Module (TCM). A bad ECM can cause harsh shifting, delayed engagement, or the transmission getting stuck in one gear (limp mode).
- ✔ Apparent Failure of Multiple Sensors: If your scanner shows error codes for multiple, unrelated sensors at once, the problem is often not the sensors themselves, but the central computer that’s reading them.
The Simple, Plug-and-Play Solution for Your 2017 Verano ECM
Replacing an ECM used to be a job reserved for the dealership, involving expensive proprietary tools and software. We’ve eliminated that hassle. This module isn’t just a part; it’s a complete service. When you purchase from us, you provide your vehicle’s 17-digit Vehicle Identification Number (VIN). Our technicians then use official GM software to flash the module with the latest, most up-to-date calibration specifically for your car. This ensures that the computer is perfectly matched to your vehicle’s engine, transmission, and factory options. It arrives at your door ready for installation, saving you hundreds of dollars in dealership programming fees and towing costs.
This module is a direct replacement for part numbers 12667002, 12666070, and 12667189 and fits a wide range of popular 2017-2019 GM vehicles. Please verify the fitment list to ensure compatibility with your specific make and model.
Installation and Setup
While professional installation is always recommended, replacing the ECM is often within reach for a skilled DIY mechanic. The module is typically located in the engine bay (e.g., on the LH side in a Regal or Equinox, or behind the fan shroud in a Traverse or Enclave). The basic process involves disconnecting the vehicle’s battery, carefully unplugging the electrical connectors from the old module, unbolting it, and then installing the new one in the reverse order. After installation, some vehicles may require a simple ‘Security Relearn’ or ‘Anti-Theft’ procedure, which can usually be done without any special tools. This often involves cycling the ignition key in a specific sequence. We highly recommend consulting a service manual for your specific vehicle for detailed instructions and torque specifications.
Frequently Asked Questions
Does this ECM come programmed?
Yes! This is the core of our service. We program the ECM with the latest GM software using the VIN you provide during checkout. It arrives ready to be installed in your vehicle, with no extra programming required.
Where do I find my vehicle’s VIN?
Your 17-digit VIN can be found on your vehicle’s registration, insurance card, or on the vehicle itself. Look for a small metal plate on the driver’s side of the dashboard (visible through the windshield) or on the sticker inside the driver’s door jamb.
Will I need to do anything else after installing the module?
In many cases, you may need to perform a simple security relearn procedure. This typically involves a 10-30 minute key cycle process that syncs the new ECM with your vehicle’s anti-theft system. This procedure does not require any special tools and instructions can be readily found online or in your vehicle’s service manual.
How do I know if this part number will fit my car?
This ECM, 12666070, is a direct replacement for part numbers 12667002 and 12667189. Please review the detailed fitment list on this page which includes models like the 2017 Caprice, Traverse, XTS, Acadia Limited, Enclave, Regal, Verano, Impala, Equinox, and Terrain. Matching your original part number or confirming your model is on the list ensures compatibility.
What happens if I forget to provide my VIN?
Providing your VIN is a critical step. We cannot ship your order until we receive your VIN, as the programming is specific to your exact vehicle. We will contact you via email to request the VIN if it is not provided at the time of purchase to avoid any delays.