Get Your Truck Back on the Road, Fast.
Is your Sierra, Silverado, or Express van running rough, refusing to start, or flashing a persistent check engine light? A failing Engine Control Module (ECM) can bring your workhorse to a grinding halt, costing you time, money, and peace of mind. This isn’t just an inconvenience; it’s a critical failure that compromises your vehicle’s reliability. Stop chasing symptoms and address the core of the problem with our professionally programmed 12663405 engine control module, the definitive solution to restore your vehicle’s performance and dependability.
Common Symptoms of a Failing ECM & Your Direct Solution
If you’re experiencing any of the following issues, a faulty engine computer is the likely culprit. This unit is the direct fix for problems such as:
- Complete no-start or intermittent starting conditions
- Rough idling, stalling, or hesitation during acceleration
- Poor fuel economy and reduced engine power
- Erratic transmission shifting behavior
- Check Engine Light (CEL) with communication codes (e.g., U0100) or multiple false sensor codes
- Cooling fans running constantly or not at all
Instead of paying for expensive diagnostic fees and dealer programming, our programmed 12663405 engine control module arrives at your door ready for installation. We use your vehicle’s VIN to flash the unit with the latest GM-certified software, ensuring perfect compatibility and optimal operation right out of the box.
Features & Tangible Benefits
- ✔ VIN-Programmed for Your Vehicle: Eliminates the need for costly dealer programming. This module is a true plug-and-play solution, designed to get you back on the road with minimal downtime.
- ✔ Loaded with Latest GM Software: We ensure your ECM is updated with the most current calibrations for improved performance, fuel efficiency, and emissions control.
- ✔ Broad Model Compatibility: This single unit replaces a wide range of part numbers (including 12668866, 12643636, and 12670335), making it a versatile solution for many GM trucks, vans, and cars.
- ✔ Restored Engine Performance: A properly functioning ECM is critical for precise fuel injection, ignition timing, and transmission control. Restore the smooth, reliable power you depend on.
- ✔ Confidence in Your Repair: This unit is backed by our one-year replacement warranty. Drive with the assurance that your vehicle’s electronic brain is solid and protected.
An Expert’s Note on Diagnostics
“We had a customer with a 2014 Sierra 2500 used for heavy towing. The truck had a persistent, random misfire that multiple shops couldn’t solve after replacing plugs, wires, and coils. The issue was a weak injector driver inside the original ECM. Once they installed our pre-programmed 12663405 engine control module, the problem was solved in under an hour. Don’t waste money throwing parts at a problem; a faulty ECM can mimic many other failures, so it’s often the most effective solution.”
Frequently Asked Questions
Do I need to have this module programmed by a dealer?
No. The main benefit of our service is that we program the module to your vehicle’s specific VIN before we ship it. It arrives ready to be installed.
What information do you need from me after I order?
After you complete your purchase, you will need to provide us with your 17-digit Vehicle Identification Number (VIN). This is essential for us to program the module correctly for your vehicle’s specific options and software.
Is the installation difficult?
For most trucks like the Sierra and Silverado, the ECM is located in the front left of the engine compartment and is straightforward to access. Installation involves disconnecting the battery, unplugging the electrical connectors, and unbolting the old unit. While it’s a DIY-friendly job for many, you may need to perform a simple security relearn procedure, which can be found in your owner’s manual or online.
Will this fix my check engine light?
This module will resolve any Diagnostic Trouble Codes (DTCs) that are directly caused by a failing ECM. If your check engine light is due to a faulty sensor or mechanical issue, you will still need to address that separate problem.
How does the one-year replacement warranty work?
If the module fails within one year of the purchase date, we will provide a direct replacement. This warranty covers the part itself, giving you confidence in your repair.
Is this compatible with part number 12668866?
Yes. This ECM, part number 12663405, is a direct replacement for several other part numbers, including 12668866, 12668994, 12643636, and others listed in the fitment data.