Restore Your Vehicle’s Performance and Reliability
Is your Chevrolet, Buick, or GMC vehicle suffering from frustrating issues like a persistent Check Engine Light, sudden stalling, rough idling, or a no-start condition? These are classic signs of a failing Engine Control Module (ECM), the central computer that manages your engine’s most critical functions. Don’t let a faulty module keep you sidelined. This genuine GM Engine Control Module, part number 12668991, is the definitive solution, arriving at your door pre-programmed with the latest factory software for your specific vehicle.
As a technician with over two decades of experience, I’ve seen firsthand how a failing ECM can cause a cascade of hard-to-diagnose problems. From erratic transmission shifting to poor fuel economy, the symptoms can be misleading. That’s why we take the guesswork out of the repair. By programming this module to your vehicle’s VIN before we ship, we eliminate the need for an expensive trip to the dealership for programming. This is a direct-fit, reliable replacement designed to restore the precise performance and efficiency you expect from your vehicle.
Case Study: A Tricky Diagnosis
I remember a 2015 Chevy Cruze that came into the shop with an intermittent no-start condition that had stumped two other mechanics. It would start fine for a week, then refuse to crank for a day. There were no consistent trouble codes, just a frustrated owner. After ruling out the battery, starter, and wiring, we focused on the ECM. On a hunch, we connected a scope and found the 5-volt reference signal would occasionally drop out. A replacement ECM, programmed correctly, solved the problem for good. This highlights how internal ECM failure can cause baffling, intermittent issues that a direct replacement like this one can fix permanently.
Is Your Vehicle Showing These Symptoms?
A failing ECM can manifest in numerous ways. If you’re experiencing any of the following, this module is likely the solution you need.
- âś” Persistent Check Engine Light (CEL)
- âś” Diagnostic Trouble Codes (DTCs) such as P0601 (Internal Control Module Memory Check Sum Error) or P0606 (ECM/PCM Processor Fault)
- âś” Unexplained drop in fuel economy
- âś” Engine stalling, stumbling, or hesitating
- âś” Complete no-start or intermittent starting problems
- âś” Rough or erratic automatic transmission shifting
- âś” Failure to pass an emissions inspection
A Straightforward Guide to Installation
Replacing your 2014-2015 Spark Engine Control Module is a manageable job for a confident DIYer or any professional technician. Our pre-programming service handles the most complex step for you.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 15 minutes for capacitors to discharge before beginning work.
- Locate the ECM: The module’s location varies by vehicle. It’s often found in the engine bay (e.g., on the firewall or inner fender) or sometimes inside the vehicle. Consult a repair manual for your specific model if you’re unsure.
- Disconnect Connectors: Carefully release the locking tabs on the electrical wiring harnesses and disconnect them from the old ECM. 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 to reuse it.
- Install the New Module: Mount your new, pre-programmed ECM in place and secure it with the original hardware.
- Reconnect and Secure: Firmly plug the wiring harnesses into the new module until they click, ensuring a solid connection. Reconnect the negative battery terminal.
- Perform Security Relearn: On many GM vehicles, a security relearn procedure (often called a Passlock or anti-theft relearn) is required. This simple procedure typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. This allows the new ECM to sync with your vehicle’s security system.
Verified Vehicle Compatibility
This module is a direct replacement for part number 12668991 and also interchanges with part numbers 12668866, 12668994, 12643636, 12663405, 12670335, 22819494, and 12692200. It is confirmed to fit a wide range of GM vehicles. Please verify your specific model and options below.
- Buick Encore: 2013-2016 (1.4L)
- Cadillac ELR: 2014-2016 (Gasoline)
- Chevrolet Cruze: 2012-2015 (Gasoline, 1.4L), 2016 (VIN P, Limited)
- 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 (Gasoline)
- GMC Savana 2500/3500 Van: 2016 (4.8L, 6.0L)
- GMC Sierra 2500/3500 Pickup: 2012-2016 (6.0L)
- GMC Sierra Denali 2500/3500: 2012-2016 (6.0L)
Frequently Asked Questions
Frequently Asked Questions
How does the programming process work?
It’s simple. After you complete your purchase, you will need to provide us with your vehicle’s 17-digit VIN. We use this to download the latest, most stable software directly from GM and flash it onto the module before shipping it to you.
Is this a plug-and-play part?
Because we pre-program the module, it is nearly plug-and-play. However, most GM vehicles will require a simple security relearn procedure after installation, which does not require any special tools. We provide instructions for this common procedure.
Will this fix my specific problem?
This module corrects all issues directly caused by a faulty ECM, including internal processor faults (P0606), memory errors (P0601), and failed driver circuits. While it’s a very common point of failure, always ensure your vehicle has been properly diagnosed by a qualified technician.
Where do I find my VIN?
Your Vehicle Identification Number (VIN) can be found on your vehicle’s registration, your insurance card, or on the driver’s side of the dashboard, visible through the windshield.
Do I need to send my old ECM back?
No core charge or return is required for this part. You can recycle your old module locally.
Why is getting the latest software important?
Automakers frequently release software updates to fix bugs, improve transmission shifting, enhance fuel efficiency, and correct other drivability issues. Our programming service ensures your replacement 2014-2015 Spark Engine Control Module has all these improvements built-in.