Restore Your Truck’s Performance and Reliability
As a technician with over two decades of experience under the hood, I’ve seen firsthand the frustration a faulty Engine Control Module (ECM) can cause. If your 2012-2016 Silverado 2500 is suffering from a persistent check engine light, poor fuel economy, erratic shifting, or a dreaded no-start condition, the problem often lies with the vehicle’s computer. The ECM is the brain of your engine, managing everything from fuel injection and ignition timing to transmission signals. When it fails, your dependable workhorse can become a major headache.
This isn’t just a replacement part; it’s a complete solution. We are offering a genuine OEM-quality Engine Control Module, part number 12668991, that comes fully programmed to your truck’s specific Vehicle Identification Number (VIN). This critical step ensures that all systems communicate correctly, right out of the box. You get the latest software updates from GM, which can resolve issues the original factory programming may have had. By providing your VIN at checkout, you eliminate the need for an expensive trip to the dealership for programming, saving you both time and hundreds of dollars.
A Technician’s Notebook
I remember a 2014 Silverado 2500 with the 6.0L that came into my bay with a bizarre set of symptoms. The check engine light was on with a U0100 code (Lost Communication with ECM/PCM), but it would only happen intermittently, usually after the truck was warm. The owner had already replaced the battery and checked grounds. We could have spent days chasing wires, but experience pointed to an internal ECM failure. The processor was failing under heat. We installed one of these VIN-programmed modules, performed the security relearn, and the problem was solved permanently. The customer was back on the road the same day, avoiding costly and inconclusive diagnostic time.
Is Your Truck Showing These Symptoms?
A failing ECM can manifest in many ways. If you’re experiencing any of the following, it’s a strong indicator that your engine’s computer needs attention:
- âś” Check Engine Light is on with communication or internal processor codes (e.g., P0601, P0606, U0100).
- âś” The engine cranks but refuses to start.
- âś” Noticeable decrease in fuel mileage.
- âś” The transmission shifts harshly or at the wrong times.
- âś” Stalling, stumbling, or hesitation during acceleration.
- âś” Unexplained loss of power.
A Straightforward Guide to Installation
Replacing the ECM on your Silverado is a manageable job for a DIYer with basic tools. Our pre-programmed module makes it even simpler. Follow these general steps to get your truck back in top shape:
- Safety First: Disconnect the negative terminal from your truck’s battery to prevent any electrical shorts.
- Locate the ECM: On the 2012-2016 Silverado HD, the ECM is typically located in the front left (driver’s side) of the engine compartment, often mounted to the fender well or a bracket near the airbox.
- Disconnect the Harnesses: Carefully release the locking tabs on the electrical connectors and pull them straight out from the module. Inspect the pins for any corrosion or damage.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. There are usually a few 10mm or 13mm bolts holding it in place.
- Install the New ECM: Mount your new, programmed ECM in the same location and secure it with the bolts. Reconnect the electrical harnesses, ensuring they click securely into place.
- Reconnect Battery & Perform Relearn: Reconnect the negative battery terminal. You will need to perform a security relearn procedure (often called a Passlock or anti-theft relearn) to allow the truck to start. This procedure is simple and typically involves cycling the key in the ignition; instructions are readily available online for your specific model.
Verified Vehicle Compatibility
While this is the primary ECM for the 2012-2016 Silverado & Sierra 2500/3500 with the 6.0L engine, its versatile design allows it to be programmed for a wide variety of other GM vehicles. Please ensure your part number is listed below or that your vehicle is on this list. This module is a direct replacement for part numbers: 12668866, 12668994, 12643636, 12663405, 12670335, 22819494, and 12692200.
- BUICK ENCORE: 2013-2016 (1.4L)
- CADILLAC ELR: 2014-2016
- CHEVROLET CRUZE: 2012-2016 (Gasoline)
- CHEVROLET EXPRESS 2500/3500 VAN: 2016 (4.8L, 6.0L)
- CHEVROLET SILVERADO 2500/3500 PICKUP: 2012-2016 (6.0L)
- CHEVROLET SONIC: 2012-2016
- CHEVROLET SPARK: 2014-2015 (Gasoline)
- CHEVROLET SUBURBAN 3500: 2016
- CHEVROLET TRAX: 2013-2016
- CHEVROLET VOLT: 2011-2015
- GMC SAVANA 2500/3500 VAN: 2016 (4.8L, 6.0L)
- GMC SIERRA 2500/3500 & DENALI: 2012-2016 (6.0L)
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) is essential for us to program the ECM with the exact software and calibrations your truck needs. This ensures perfect compatibility with your engine, transmission, and other onboard systems, making the installation process smooth and effective.
Is this ECM difficult to install myself?
No, for someone with basic mechanical skills, it’s a very manageable job. Since we pre-program the module, the most complex part is already done. You’ll just need to physically swap the modules and perform a simple key-cycle security relearn procedure.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the ECM (common codes include P0601, P0606, or U0100), then yes, this part is the correct fix. It’s crucial to properly diagnose the issue first, as other sensors or wiring problems can also trigger a check engine light.
What does ‘security relearn’ mean?
The security relearn is a simple, required procedure that syncs the new ECM with your vehicle’s anti-theft system. Without it, the truck will not start. It typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. Specific instructions are easy to find for your truck.
Is this a new or used part?
This is a high-quality, inspected, and tested recycled OEM part. Each module is verified to be fully functional before being programmed with the latest GM software for your specific VIN, ensuring reliability and performance that meets or exceeds the original.