Description
2012 GMC Sierra 4.8L ECM / ECU – VIN Programmed | Plug & Play
This Engine Control Module (ECM / ECU) is a genuine OEM replacement for all 2012 GMC Sierra 4.8L models.
Each unit is VIN-programmed, updated, and fully tested for a true plug-and-play installation with no dealer visit required.
Built to OEM standards for reliability, calibration accuracy, and long-term performance.
Strict Testing & Quality Assurance
Every ECU is inspected, refreshed, and verified through advanced diagnostic tools. Testing includes:
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Complete communication & CAN-bus verification
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Sensor input/output and signal integrity checks
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Injector & ignition pulse simulation
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Power, ground, and load-circuit analysis
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Flash memory integrity and checksum validation
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Thermal and voltage-stress testing to confirm reliability
This ensures a fully functional, reliable, plug-and-play module you can install with confidence.
Important Note
Some vehicles equipped with IMMO (Immobilizer) or PATS (Passive Anti-Theft System) may require additional key programming after installation. This is normal for models where security data must be synchronized with the vehicle’s body control system.
For a 100% plug-and-play solution with no relearns, no key programming, and no compatibility issues, we recommend our ECU Cloning Service, which transfers all original security, immobilizer, and configuration data directly into the replacement unit.
Contact Us
Email: info@fixecm.com
Phone: Local: 647-247-8555 | Toll-Free: 1-800-915-5566




Lucas Evans –
The ECM arrived quickly and was truly plug-and-play—my Sierra fired up without a hitch. Couldn’t be happier with the seamless install!
Fast shipping and a perfect fit for my 2012 GMC Sierra. The VIN programming saved me a lot of hassle, highly recommend!
Installed this ECM in under 30 minutes, no extra programming needed. Smooth transaction and excellent support made all the difference.
This ECU worked perfectly right out of the box with my 2012 Sierra. Fast delivery and hassle-free setup—exactly what I needed!
Super impressed with how easy the install was; the VIN programming meant zero compatibility issues. Definitely a five-star purchase!
Paul Wright –
Swapping out the ECM on my 2012 GMC Sierra was a breeze with this VIN programmed unit. It arrived quickly and fit perfectly without any hassle, which saved me a lot of time and frustration. After installation, the truck fired up right away and runs just like new. The quality and service definitely exceeded my expectations.