Is your Cadillac, Chevrolet, or GMC vehicle suffering from erratic behavior, a persistent check engine light, or a no-start condition? The Engine Control Module (ECM), often called the vehicle’s main computer, is the brain behind your engine’s performance, fuel economy, and emissions. When it fails, it can cause a cascade of frustrating and difficult-to-diagnose problems. This genuine GM Engine Control Module, part number 12663391, is the definitive solution to restore your vehicle’s factory performance and reliability.
Unlike a generic part from a local auto parts store, this ECM is delivered to you fully programmed to your vehicle’s specific Vehicle Identification Number (VIN). We flash it with the latest, most stable software updates directly from General Motors. This critical step ensures seamless communication with all other modules in your vehicle, from the transmission to the anti-lock brakes. This eliminates the need for an expensive trip to the dealership for programming, saving you both time and money. The module arrives ready for a straightforward installation process.
We had a 2015 Silverado 1500 come into the shop with a complaint of intermittent stalling and a flashing check engine light. The customer had already replaced the spark plugs, ignition coils, and even the mass airflow sensor with no success. The diagnostic codes were all over the place—misfire codes, communication errors, and O2 sensor faults. After hours of chasing electrical gremlins, we connected a scope to the injector drivers at the ECM. We found that the signal for cylinder 3 was dropping out randomly. A new, properly programmed ECM fixed every single issue. It’s a powerful reminder that the ECM governs everything, and when it fails, it can mimic a dozen other problems.
Common Symptoms of a Failing ECM
- ✔ Check Engine Light is illuminated with various, often inconsistent, trouble codes.
- ✔ Engine stalling or misfiring for no apparent reason.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ Vehicle fails to start, even with a good battery and starter.
- ✔ Poor or rough engine performance, including hesitation during acceleration.
- ✔ Problems with automatic transmission shifting.
- ✔ Communication errors with diagnostic scan tools.
Your Plug-and-Play 2014-2016 XTS Engine Control Module Solution
The ECM is a complex and vital component. It processes information from dozens of sensors throughout your engine to control fuel injection, ignition timing, and emissions systems. A failing module can leave you stranded and facing a confusing repair. Our process simplifies the replacement. By providing us with your VIN during checkout, you ensure that the 2014-2016 XTS Engine Control Module you receive is a perfect match for your vehicle’s specific configuration and options. It’s built to meet or exceed OEM specifications for durability and performance.
This module is a direct replacement for a wide range of popular GM trucks and cars, ensuring broad compatibility. Please verify your original part number against our list to guarantee a perfect fit. This unit is compatible with the following part numbers: 12692067, 12676230, 12656993, 12662034, 12672537, 12673195, 12663391, 12672963, and 12669318.
Installation and Additional Procedures
While this module is sent programmed to your VIN, some vehicles may require an additional security relearn procedure or crankshaft position sensor relearn procedure after installation. These procedures can often be completed without special tools and instructions are widely available. This is a standard part of the process for many modern vehicles and ensures the anti-theft system recognizes the new module. By purchasing this pre-programmed 2014-2016 XTS Engine Control Module, you are handling the most complex part of the job before the part even arrives at your door.
Frequently Asked Questions
What information do you need to program the ECM?
We require your vehicle’s 17-digit Vehicle Identification Number (VIN) to program the module. Please provide this number in the notes section during checkout or send it to us via email after your purchase. This ensures the ECM has the correct software for your vehicle’s specific options.
Is this a simple plug-and-play installation?
Yes, for the most part. The module is programmed to your VIN, which handles the most difficult step. However, depending on your specific vehicle, you may need to perform a security relearn or a crankshaft variation relearn procedure. These are standard procedures and do not typically require a trip to the dealer.
Will this fix my check engine light?
If the check engine light and associated symptoms are caused by a faulty ECM, then this replacement part will resolve the issue. It’s crucial to have a proper diagnosis performed to confirm the ECM is the root cause of the problem before ordering.
How do I find my original part number?
The part number is printed on a sticker on your original ECM. You may need to remove the module from the vehicle to see it clearly. Matching this number to the list of compatible part numbers in our description is the best way to ensure a correct fit.
Does this part come with a warranty?
Yes, all of our electronic modules come with a standard warranty against defects. Please refer to our warranty policy page for complete details and duration.