Is Your Sierra 2500 Experiencing Frustrating Engine Problems?
If your 2012-2016 GMC Sierra 2500 is suffering from a no-start condition, erratic shifting, a persistent Check Engine Light, or random stalling, a failing Engine Control Module (ECM) is often the culprit. As the brain of your truck’s engine, when the ECM begins to fail, it can cause a cascade of confusing and performance-robbing issues. You need a reliable solution that gets your heavy-duty truck back on the road without the hassle and expense of a dealership visit.
The Direct-Fit, Programmed Solution for Your Truck
This is a genuine GM Engine Control Module, part number 12670335, which arrives at your door fully programmed to your truck’s specific Vehicle Identification Number (VIN). We handle the complex part for you. By flashing the module with the latest GM-certified software updates before it ships, we ensure it communicates flawlessly with your vehicle’s other systems right out of the box. This eliminates the need for expensive dealer-only programming tools or additional labor costs.
Expert Real-World Diagnosis: “A customer’s 2014 Sierra 2500 with the 6.0L came into my shop last month with a complaint of intermittent stalling at stoplights and a whole host of communication error codes (U-codes) that would come and go. The parts cannon had already been fired at itโnew throttle body, new MAF sensorโwith no change. After verifying the main power and ground circuits to the ECM were solid, we knew the internal logic of the module itself was failing. Swapping in a VIN-programmed module like this one resolved all the codes and the stalling issue on the first test drive. It’s a common failure point I’ve seen dozens of times on these workhorses.”
Why Choose Our Pre-Programmed ECM?
- โ VIN-Specific Programming: We flash the module with your truck’s VIN, ensuring perfect compatibility with its specific options and systems.
- โ Latest GM Software: Your new ECM will be loaded with the most current software available, often correcting factory bugs and improving performance and fuel efficiency.
- โ No Dealer Required: This module is ready for installation upon arrival, saving you time and hundreds of dollars in dealership programming fees.
- โ Solves Common Issues: A direct solution for symptoms like harsh automatic transmission shifts, false sensor codes, poor fuel economy, and no-start conditions related to the ECM.
Easy Installation for the 2012-2016 Sierra 2500 ECM
Replacing the ECM on your Sierra is a straightforward process you can do in your own driveway. The module is located in the front left (driver’s side) of the engine compartment.
- Safety First: Disconnect the negative terminal from your truck’s battery.
- Locate the ECM: Find the module on the driver’s side of the engine bay, near the firewall or inner fender.
- Disconnect Connectors: Carefully unlatch and remove the main electrical wiring harnesses from the old module. Inspect the pins for any signs of corrosion or damage before proceeding.
- Remove Old Module: Unbolt the old ECM from its mounting bracket.
- Install New Module: Bolt the new, programmed ECM into place.
- Reconnect Everything: Securely plug the wiring harnesses into the new module until they click. Reconnect the negative battery terminal.
- Final Step: Your truck is now ready to start. In some cases, a security relearn procedure may be required, which can typically be done without special tools by cycling the key.
Guaranteed Compatibility
This module is a direct replacement for a wide range of GM vehicles and part numbers. If your original module has any of the following numbers, this part is the correct fit for you:
Replaces Part Numbers: 12668866, 12668994, 12643636, 12663405, 12670335, 22819494, 12692200
While this listing is focused on the 2012-2016 Sierra 2500 PICKUP with the 6.0L engine, it also fits a broad array of other GM models, including the Silverado 2500/3500, Express/Savana Vans, Cruze, Sonic, and more. Providing your VIN during checkout guarantees we send you the correctly programmed part for your exact vehicle.