Is your 2014-2016 Sierra Denali 1500 acting up? If you’re dealing with frustrating issues like random stalling, a persistent check engine light, poor fuel economy, or a complete no-start condition, the problem often points directly to a failing Engine Control Module (ECM). As the ‘brain’ of your truck’s engine, the ECM is responsible for managing everything from fuel injection and ignition timing to transmission shifting. When it fails, it can cause a cascade of problems that are often difficult to diagnose.
This isn’t just a replacement part; it’s a complete solution. We are offering a genuine GM Engine Control Module, part number 12669318, that comes fully programmed to your specific vehicle. Before we ship it, we flash the module with the very latest GM-certified software updates using your truck’s Vehicle Identification Number (VIN). This critical step ensures perfect communication between the ECM and all other systems in your vehicle, restoring the performance and reliability you expect. By providing us with your VIN at checkout, you eliminate the need for an expensive trip to the dealership for programming. You get a part that is truly ready for installation right out of the box.
A Technician’s Notebook
I remember a 2015 Silverado that came into the bay on a tow truck. The owner had spent a fortune at other shops chasing a ghost—the truck would run fine for days, then suddenly die at a stoplight and refuse to restart for an hour. There were no consistent codes, just a random U0100 (Lost Communication with ECM). After checking all the wiring and grounds, we suspected the ECM itself was failing internally when it got hot. We installed one of our pre-programmed modules, performed the security relearn, and the truck has been running without a single hiccup for over a year. These intermittent issues are classic signs of a failing ECM, and a pre-programmed module is the most reliable fix.
Is Your Truck Showing These Symptoms?
A faulty 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 codes like P0601, P0606 (ECM Processor Fault) or communication codes (U-codes).
- âś” Engine cranks but will not start.
- âś” Intermittent stalling, especially when the engine is warm.
- âś” Noticeable drop in fuel mileage.
- âś” Rough or unstable idle.
- âś” Transmission shifting harshly or at the wrong times.
- âś” Other warning lights on the dash, such as for the traction control or stabilitrak system.
A Straightforward Guide to Installation
Installing your new 2014-2016 Sierra Denali 1500 ECM is a manageable job for a DIYer with basic tools. Since the module comes programmed, you skip the hardest part. After physical installation, you will need to perform a security relearn procedure so the vehicle recognizes the new module. This procedure does not require a special scan tool.
- Safety First: Disconnect the negative terminal from your truck’s battery.
- Locate the ECM: On most GM trucks from this era, the ECM is located in the front of the engine compartment on the driver’s side, near the air filter box.
- Disconnect Connectors: Carefully release the locking tabs and unplug the wiring harness connectors from the old ECM. Inspect them for any corrosion or damage.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Bolt the new, pre-programmed ECM into place and securely reconnect the wiring harnesses.
- Reconnect Battery: Reattach the negative battery terminal.
- Perform Security Relearn: Turn the key to the ‘ON’ position (do not start the engine). The security light may be flashing. Leave the key on for 10-12 minutes, or until the security light turns off. Turn the key off for 10 seconds. Repeat this cycle two more times for a total of three cycles. After the third cycle, the vehicle will have learned the new ECM, and you can start the engine.
Verified Vehicle Compatibility
This module is a direct replacement for part number 12669318 and is compatible with several other service numbers. It fits a wide range of GM vehicles. Please verify your vehicle is on the list below. Providing your VIN is the best way to guarantee perfect fitment.
ATS 14-16, CAMARO 16, CANYON 15-16, COLORADO 15-16, CORVETTE 14-16, CTS 14-16, ESCALADE 15-16, ESCALADE ESV 15-16, SIERRA 1500 PICKUP 14-16, SIERRA DENALI 1500 14-16, SILVERADO 1500 PICKUP 14-16, SUBURBAN 1500 15-16, TAHOE 15-16, XTS 14-16, YUKON 15-16, YUKON XL 1500 15-16.
Note: Specific engine and option codes may apply. Supplying your VIN ensures we program the module correctly for your exact vehicle configuration.
Frequently Asked Questions About Your ECM
Why do you need my VIN?
Why do you need my VIN?
Your Vehicle Identification Number (VIN) contains critical information about your truck’s specific options, engine, transmission, and emissions systems. We use the VIN to load the exact, correct GM software and the latest updates onto the ECM before shipping. This ensures it works perfectly with your vehicle, just like a module from the factory.
Is this part difficult to install?
No, the physical installation is straightforward. It involves disconnecting the battery, unplugging a few connectors, and unbolting the module. The most important step after installation is the security relearn procedure, which we detail in our guide. It takes about 30 minutes and does not require any special tools, making this a very DIY-friendly repair.
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 related communication errors, then yes, this module will resolve the issue. However, if the light is on for another reason, such as a bad sensor, that separate issue will still need to be addressed.
Is this a new or used part?
This is a high-quality, tested, and verified OEM part that is guaranteed to function to factory specifications. Each module is inspected and then programmed with new, vehicle-specific software, ensuring reliable performance.
What if my original part number is different?
GM often supersedes part numbers over the years. This module, 12669318, is the compatible service replacement for several older part numbers, including 12692067, 12676230, and 12656993, among others. As long as your vehicle is on our compatibility list, this module will work once programmed to your VIN.