Restore Peak Performance to Your GM Truck or Car
Is your 2012-2016 Silverado 2500, Sierra, or another GM vehicle acting up? Stalling unexpectedly, shifting erratically, or displaying a persistent Check Engine Light can be more than just an annoyance—it can sideline your workhorse. As the central command center for your engine, a failing Engine Control Module (ECM) is often the root cause of these frustrating and hard-to-diagnose issues. This isn’t just a replacement part; it’s a direct solution, pre-programmed with the latest official GM software specifically for your vehicle’s VIN. You get a reliable fix that restores factory performance and communication without a costly trip to the dealership for programming.
Case Study: The Intermittent No-Start
A customer brought in a 2014 Sierra 2500 with the 6.0L V8. The complaint was maddening: some mornings it would start perfectly, others it would just crank with no fire. They had already replaced the fuel pump and crank sensor with no luck. After connecting my scan tool, I noticed intermittent communication loss with the ECM (a classic U0100 code). On a hunch, I checked the ECM’s internal temperature data and saw erratic readings. In my 20+ years, I’ve seen this hundreds of times—internal circuit board failure due to heat cycles and vibration. We installed one of our VIN-programmed ECMs, and the truck has started flawlessly ever since. This part saved the customer from chasing phantom electrical gremlins for weeks.
Is Your GM Vehicle Showing These Red Flags?
A failing ECM can manifest in numerous ways. If you’re experiencing any of the following, this module is the likely solution your vehicle needs.
- ✔ Engine stalling or misfiring for no apparent reason
- ✔ Complete no-start condition where the engine cranks but won’t turn over
- ✔ Drastic decrease in fuel economy
- ✔ Harsh or erratic automatic transmission shifting
- ✔ Check Engine Light with codes like P0601, P0606 (Internal Control Module Failure), or U0100 (Lost Communication with ECM/PCM)
- ✔ Inconsistent performance that comes and goes with temperature changes
A Straightforward Guide to Installation
Getting your vehicle back in top shape is easier than you think. This module is designed for a direct-fit replacement. While a security relearn procedure is typically required, the physical swap is simple.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before beginning any electrical work.
- Locate the ECM: On most Silverado and Sierra HD trucks, the ECM is located in the front of the engine bay on the driver’s side, near the battery and airbox.
- Disconnect and Remove: Carefully unplug the electrical connectors. They have locking tabs that need to be released. Once disconnected, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed ECM into place. Firmly reconnect the electrical harnesses, ensuring they click and lock securely.
- Reconnect Power: Reattach the negative battery terminal and tighten it.
- Perform Security Relearn: Most GM vehicles require a security relearn procedure to allow the vehicle to start. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’, and repeating two more times. Consult your vehicle’s specific procedure for exact steps.
Verified Compatibility Across the GM Family
This Engine Control Module is a direct replacement for part number 12663405 and other interchangeable numbers like 12668866, 12668994, and 12643636. It is confirmed to fit a wide range of GM vehicles, including but not limited to:
- Chevrolet Silverado 2500/3500 Pickup (2012-2016) with 6.0L engine
- GMC Sierra 2500/3500 & Denali (2012-2016) with 6.0L engine
- Chevrolet Express 2500/3500 Van (2016) with 4.8L or 6.0L engine
- GMC Savana 2500/3500 Van (2016) with 4.8L or 6.0L engine
- Chevrolet Cruze (2012-2016) with 1.4L engine or specific IDs
- Chevrolet Sonic (2012-2016) with 1.4L engine or specific IDs
- Buick Encore (2013-2016) with 1.4L engine
- Chevrolet Trax (2013-2016)
- Cadillac ELR (2014-2016)
- Chevrolet Volt (2011-2015)
- Chevrolet Spark (2014-2015) gasoline models
- Chevrolet Suburban 3500 (2016)
IMPORTANT: We program this module using the VIN you provide at checkout. This ensures it communicates perfectly with your vehicle’s specific options and systems. Please double-check your VIN for accuracy before submitting your order.
Frequently Asked Questions
How do I provide my VIN for programming?
After you complete your purchase, you will receive an email prompting you for your vehicle’s 17-digit VIN. You can also add it as a note during the checkout process. We cannot ship your part until we receive this information, as the programming is essential for the part to function.
What does “pre-programmed” mean for me?
It means this ECM arrives ready to install. We load the latest GM-certified software that matches your vehicle’s VIN. This saves you a trip to the dealer and the high cost of their programming service, making this a true plug-and-play solution (after the security relearn).
Will I need to perform any other programming after installation?
No. The critical engine and transmission programming is complete. The only procedure required is the vehicle’s anti-theft security relearn, which syncs the new ECM to your key. This is a simple procedure you can do yourself in about 30 minutes with no special tools.
Is this compatible with other part numbers?
Yes. This module is a direct replacement for several part numbers, including 12668866, 12668994, 12643636, 12670335, 22819494, and 12692200. If your original module has one of these numbers, this part will work for you.
What if my vehicle isn’t a Silverado or Sierra?
This ECM fits a very wide range of GM vehicles. Please review the detailed compatibility list on this page. As long as your make, model, year, and engine match one of the entries, this module will fit and function correctly once programmed to your VIN.