Restore Your Truck’s Power and Reliability
Is your 2012-2016 Silverado 3500 suffering from a persistent Check Engine Light, erratic performance, or a frustrating no-start condition? The Engine Control Module (ECM) is the brain of your truck’s 6.0L engine, managing everything from fuel injection and spark timing to transmission shifting. When it fails, it can cause a cascade of problems that are often difficult to diagnose. This direct-fit ECM, part number 12668866, is the definitive solution to get your workhorse running like new again.
What sets this module apart is our complimentary VIN programming service. Before we ship your part, we flash it with the latest official GM software specific to your truck’s Vehicle Identification Number. This critical step ensures seamless communication with your vehicle’s other electronic systems, eliminating the need for an expensive trip to the dealership for programming. It’s a true plug-and-play solution designed to save you time and money.
A Technician’s Notebook
I remember a 2014 Silverado 2500 (which uses the same ECM) that came into my shop with a complaint of intermittent stalling at stoplights and a P0601 code (Internal Control Module Memory Check Sum Error). The owner had already replaced the spark plugs and MAF sensor with no luck. After verifying power and ground to the ECM, it was clear the module itself was failing internally. We installed one of these pre-programmed units, and the problem was solved in under 30 minutes. The customer was thrilled to avoid a hefty dealership bill and get his reliable truck back on the road fast.
Common Signs of a Failing ECM
- ✔ Check Engine Light is on with communication codes (like U0100) or internal processor codes (P0601, P0606).
- ✔ Engine cranks but refuses to start.
- ✔ Unexplained drop in fuel economy.
- ✔ Rough or unstable idle.
- ✔ The engine stalls unexpectedly while driving or at idle.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Noticeable loss of engine power and poor acceleration.
A Straightforward Guide to Installation
Installing your new 2012-2016 Silverado 3500 ECM is a manageable job for a DIYer with basic tools. Follow these steps for a successful replacement.
- Safety First: Disconnect the negative terminal from your truck’s battery to prevent any electrical shorts.
- Locate the ECM: On your Silverado, the ECM is found in the left-hand (driver’s side) front of the engine compartment, typically mounted near the battery or air filter housing.
- Disconnect the Connectors: Carefully release the locking tabs on the electrical wiring harnesses and pull them straight out from the module. Avoid pulling on the wires themselves.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep the hardware, as you may need it for the new installation.
- Install the New ECM: Mount the new module securely onto the bracket and reconnect the wiring harnesses. You’ll hear a click when they are properly seated.
- Reconnect the Battery: Reattach the negative battery terminal and tighten it securely.
- Final Steps: In most cases, no further action is needed. The vehicle may need to complete a drive cycle for all emissions monitors to become ready. Start the engine and check for proper operation and ensure the Check Engine Light is off.
Will This Fit My Vehicle?
This ECM is a guaranteed fit for the 2012-2016 Silverado 3500 PICKUP with the 6.0L engine. It is also a direct replacement for part numbers 12668866, 12668994, 12643636, 12663405, 12670335, 22819494, and 12692200, and fits a wide range of other GM vehicles, including:
- ✔ 2012-2016 Chevrolet Silverado 2500 / 3500 (6.0L)
- ✔ 2012-2016 GMC Sierra 2500 / 3500 & Denali models (6.0L)
- ✔ 2016 Chevrolet Express / GMC Savana 2500 & 3500 Vans (4.8L, 6.0L)
- ✔ 2016 Chevrolet Suburban 3500
- ✔ And many other GM models including the Cruze, Sonic, Trax, Encore, Volt, and ELR. Please verify your part number to ensure compatibility.
By purchasing this 2012-2016 Silverado 3500 ECM, you are getting a reliable, fully tested component that restores your truck’s factory performance and drivability without the dealership hassle.
Frequently Asked Questions
Do I need to do anything after I install this ECM?
No. Because we program the module to your VIN before shipping, it is ready for installation right out of the box. In some rare cases, a security relearn procedure may be necessary, which can typically be done without special tools by cycling the key.
How do I provide my VIN?
After you complete your purchase, you will need to send us your 17-digit Vehicle Identification Number (VIN). We cannot program and ship the module without it. You can typically add it as a note during checkout or send it to us in a message referencing your order number.
What if my original part number is not 12668866?
This module is a direct replacement for several part numbers, including 12668994, 12643636, and others listed in the description. As long as your original module’s part number is on our cross-reference list, this part will work for you.
Is this a guaranteed fix for my truck’s problems?
This ECM will fix problems directly caused by a faulty module. While the symptoms listed are common for ECM failure, they can also be caused by other issues. Proper vehicle diagnosis is always recommended. However, if you have confirmed the ECM is the culprit with codes like P0601, this is the solution.