Restore Your Truck’s Core Performance and Reliability
Is your GMC Sierra or Silverado running rough, stalling unexpectedly, or showing a persistent check engine light? These are classic signs that the brain of your engine—the Engine Control Module (ECM)—may be failing. As a technician with over two decades of experience, I’ve seen firsthand how a faulty ECM can cause a cascade of frustrating and hard-to-diagnose issues, from poor fuel economy to erratic shifting. This isn’t just an inconvenience; it’s a reliability problem that can leave you stranded. This replacement Engine Control Module, part number 12674472, is the definitive solution to restore your vehicle’s factory performance and peace of mind.
We take the guesswork and dealership hassle out of the equation. Before this module ships, we program it specifically to your truck using your Vehicle Identification Number (VIN). This means it arrives loaded with the latest, most stable software updates directly from GM. You get a component that is precisely matched to your vehicle’s specifications, ensuring optimal engine performance, fuel efficiency, and emissions control right out of the box. This is the same level of precision you’d get from a dealership, without the high cost or the need to have your truck towed in for programming.
Is Your Truck Showing These Telltale ECM Failure 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. In the shop, we often see these issues accompanied by diagnostic trouble codes (DTCs) like P0601, P0606, or U0100.
- ✔ Unexplained Check Engine Light that won’t go away.
- ✔ Engine stalling, sputtering, or misfiring for no apparent reason.
- ✔ A noticeable drop in fuel mileage.
- ✔ Harsh or unpredictable automatic transmission shifting.
- ✔ The engine cranks but refuses to start (no-start condition).
- ✔ Communication errors with other vehicle modules.
From the Diagnostic Bay: The Case of the Intermittent No-Start
A customer brought in his 2017 Sierra 1500 with a problem that was driving him crazy. The truck would start and run perfectly for days, then suddenly refuse to start. No crank, no click, nothing. After it sat for a few hours, it would fire right up again. His local shop had replaced the battery and starter to no avail. When I hooked up my scan tool, I found intermittent communication loss codes with the ECM. On these GM trucks, the ECM is mounted on the front driver’s side of the engine compartment, where it’s exposed to intense heat cycles and vibration. Over time, this can cause internal solder joints on the circuit board to fail. We confirmed the diagnosis, ordered a VIN-programmed 2016-2018 Sierra 1500 ECM, and installed it. The customer called a month later to say his truck hadn’t missed a beat since. It’s a classic failure mode where a pre-programmed module is the fastest, most reliable fix.
Your Straightforward Installation Guide
Replacing the ECM is a manageable job for a confident DIYer or any professional technician. Follow these steps carefully for a smooth installation. Remember to provide us with your VIN upon purchase so we can program the module for you.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 15 minutes for the system capacitors to discharge.
- Locate the ECM: On most 2016-2018 Sierra and Silverado models, the ECM is located on the driver’s side of the engine compartment, near the air filter housing.
- Disconnect the Connectors: Carefully release the locking tabs on the electrical connectors and pull them straight out from the module. Never force them. Inspect the pins for any corrosion or damage.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep the hardware as you will need it for the new module.
- Install the New Module: Mount your new, pre-programmed ECM onto the bracket and secure it with the original hardware.
- Reconnect Everything: Firmly plug the electrical connectors back into the new ECM until they click into place. Reconnect the negative battery terminal.
- Perform Relearn Procedures: Turn the key to the ‘ON’ position. In many cases, the truck will start and run. However, if it does not start, a Vehicle Theft Deterrent System (VTDS) relearn is required. This procedure pairs the new ECM to your vehicle’s security system and requires a GM-compatible scan tool with access to Tis2web or Techline Connect. Other procedures, like a crankshaft variation relearn, may also be necessary to clear certain codes and ensure perfect operation. This is the final and most critical step.
Will This Fit My Vehicle? Verified Compatibility
This Engine Control Module is a direct-fit replacement for a wide range of GM trucks and SUVs. Please verify your vehicle and part number from the list below. This module is compatible with part numbers 12692068, 12704476, 12686382, 12674052, 12674472, and 12678815.
- ✔ 2016-2018 GMC Sierra 1500 / Sierra Denali 1500
- ✔ 2016-2018 Chevrolet Silverado 1500
- ✔ 2017 Cadillac Escalade / Escalade ESV
- ✔ 2017 Chevrolet Tahoe / Suburban 1500
- ✔ 2017 GMC Yukon / Yukon XL 1500
- ✔ 2017 Cadillac ATS, CTS, XTS (specific engines, check notes)
- ✔ 2017 Chevrolet Corvette
Frequently Asked Questions About Your 2016-2018 Sierra 1500 ECM
Frequently Asked Questions
Why do you need my VIN?
Your VIN is essential. We use it to load the exact, factory-correct software and calibrations for your truck’s specific engine, transmission, and options. This ensures seamless integration and performance without a trip to the dealer for programming.
What is a ‘theft relearn’ and will I need to do it?
The theft relearn (or VTDS relearn) synchronizes the new ECM with your vehicle’s anti-theft system. If the truck doesn’t start after installation, this procedure is necessary. It requires a professional scan tool with access to GM’s software (like Techline Connect). It is the responsibility of the installer.
Is this a plug-and-play part?
It is ‘plug-and-program.’ We handle the complex programming to your VIN before shipping. You handle the physical installation and any necessary post-installation relearn procedures, such as the theft relearn or crankshaft position variation relearn.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the old ECM (like DTC P0601), then yes, this new module will resolve the issue once installed correctly and any related codes are cleared.
What other part numbers does this replace?
This module is a direct replacement for several part numbers, including 12692068, 12704476, 12686382, 12674052, 12674472, and 12678815, ensuring broad compatibility.