Restore Your Vehicle’s Core Performance and Reliability
As a technician with over two decades of experience under the hood, I’ve seen firsthand how a failing Engine Control Module (ECM) can turn a reliable vehicle into a source of constant frustration. Erratic idling, poor fuel economy, a persistent Check Engine Light, or even a no-start condition can often be traced back to this critical component—the brain of your engine. If you’re facing these issues with your GM vehicle, you’ve found the definitive solution. This isn’t just a replacement part; it’s a fully programmed, ready-to-install module that restores your vehicle’s factory-specified operation.
We take the guesswork and extra cost out of the equation. Before this module ships, our experts will program it with the very latest GM software updates using the Vehicle Identification Number (VIN) you provide. This ensures perfect communication between the module and your vehicle’s specific systems, often correcting underlying software issues that the original module may have had. This professional programming service, included with your purchase, means you can skip the expensive trip to the dealership for flashing. For the professional mechanic, this means faster bay turnover. For the DIYer, it means a confident, straightforward repair at home.
A Technician’s Notebook: The Intermittent Stall Case
A customer brought in a 2014 Cruze with a maddening problem: it would randomly stall at stoplights, but not throw a specific engine code—just a generic U0100 ‘Lost Communication with ECM’ code that would sometimes appear. We checked wiring, grounds, and power feeds, all of which tested fine. After hours of diagnostics, experience pointed to an internal ECM failure. The module was failing intermittently under specific thermal conditions. We installed one of our pre-programmed ECMs, and the problem was solved instantly. The customer was back on the road the same day, avoiding a lengthy and costly diagnostic process at the dealer. This is a classic scenario where a quality, tested 2012-2016 Cruze Engine Module is the only real fix.
Is Your GM Vehicle Showing These Signs?
A failing ECM can manifest in numerous ways. If you’re experiencing any of the following, this module is the likely solution. Proper diagnosis is always recommended, but these are the tell-tale symptoms I see most often in my shop:
- ✔ Persistent Check Engine Light (CEL)
- ✔ Engine stalling, stumbling, or misfiring
- ✔ No-start or hard-start conditions
- ✔ Noticeable decrease in fuel efficiency
- ✔ Poor or erratic automatic transmission shifting
- ✔ Communication error codes such as P0601, P0606, or U0100
- ✔ Failure to pass emissions testing
A Straightforward Guide to Installation
Installing your new 2012-2016 Cruze Engine Module is a manageable job for a confident DIYer with basic tools. Following these steps will ensure a smooth process.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 15 minutes to allow the system to fully discharge.
- Locate the Module: On most supported models like the Cruze, Sonic, or Trax, the ECM is located in the engine bay. On vans and trucks, it’s often on the LH side of the engine compartment. Consult a vehicle-specific guide if you’re unsure.
- Disconnect and Remove: Carefully unlock and unplug the main wiring harness connectors. Be gentle, as these plastic clips can become brittle over time. Once disconnected, unbolt the module from its mounting bracket.
- Install the New Module: Bolt your new, pre-programmed module into place. Firmly reconnect the wiring harnesses, ensuring they click and lock securely. A clean, tight connection is critical.
- Reconnect and Test: Reconnect the negative battery terminal. Your vehicle may require a simple security relearn procedure (often turning the key to ‘ON’ for 10-15 minutes), but no further programming is needed. Start the engine and check for proper operation.
Verified Vehicle Compatibility
This ECM is a direct-fit replacement for a wide range of GM vehicles and interchanges with multiple part numbers, including 12668866, 12668994, 12643636, and more. Please verify your model and options below to ensure a perfect match for your 2012-2016 Cruze Engine Module needs and beyond.
CRUZE 15 (Gasoline, ID 12643636 or 12668866)
CRUZE 16 (VIN P – Limited)
SONIC 12-14 (1.4L or ID 12643636)
SONIC 15 (ID 12643636 or 12668866)
SONIC 16
TRAX 13-16 (1.4L)
ENCORE 13-16 (1.4L)
ELR 14-16
VOLT 11-15
SPARK 14-15 (Gasoline)
SILVERADO/SIERRA 2500/3500 12-16 (6.0L)
EXPRESS/SAVANA 2500/3500 16 (4.8L or 6.0L)
SUBURBAN 3500 16
Note: This is a partial list. Please see the full fitment data or contact us to confirm compatibility.
Frequently Asked Questions
Frequently Asked Questions
What do I need to do after I purchase this ECM?
After placing your order, you must provide us with your vehicle’s 17-digit VIN. We cannot program and ship the module without it. You can add the VIN in the order notes or send it to us in a message.
Is this module truly plug-and-play?
Yes, for over 95% of vehicles. It arrives programmed to your VIN with the latest software. In some cases, a simple, tool-free security relearn procedure (like the key-on method) may be necessary, which takes about 10-15 minutes.
Where can I find my VIN?
Your VIN is located on a tag on the driver’s side of the dashboard (visible through the windshield), on the driver’s side door jamb sticker, and on your vehicle’s registration and insurance documents.
Will this fix my car’s specific problem?
This module will resolve any issue directly caused by a faulty ECM. While the symptoms we’ve listed are common indicators, we always recommend a thorough diagnosis by a qualified mechanic to rule out other potential causes like wiring or sensor faults.
My original module has a different part number. Will this still work?
Yes. This ECM, part number 12670335, is the updated replacement for several older part numbers, including 12668866, 12668994, 12643636, and others listed in the description. We program it to function perfectly for your specific vehicle.
What if I have questions during installation?
Our team of experienced technicians is here to help. We provide support to ensure your installation is a success. We’re committed to getting you back on the road.