Restore Peak Performance to Your Vehicle’s Engine
Is your Chevrolet Caprice, or another compatible GM vehicle, suffering from perplexing issues like a persistent check engine light, sudden stalling, poor fuel economy, or a complete no-start condition? The Engine Control Module (ECM), the central computer of your vehicle’s powertrain, is often the root cause. This fully tested, genuine used ECM, part number 12633555 (interchangeable with 12653998, 12655007, and 12644446), is the definitive solution to get your vehicle running reliably again.
Unlike a generic module from a parts store, this ECM is specifically programmed to your vehicle’s unique Vehicle Identification Number (VIN) before it ships. We flash it with the latest GM factory software updates, ensuring optimal performance, fuel efficiency, and emissions control. This critical programming step means you receive a part that is ready for installation, often eliminating the need for an expensive trip to the dealership for further programming.
We had a 2015 Caprice PPV in the shop with an intermittent no-start and random stalling that was driving the owner crazy. No diagnostic codes were stored consistently. We checked fuel pressure, spark, and wiring harnesses for hours. On a hunch, we monitored the ECM’s data stream and noticed it would occasionally drop all communication right before a stall. We ordered a pre-programmed module like this one, swapped it in, performed the quick security relearn, and the car fired up instantly. The problem was completely gone. It’s a reminder that when the vehicle’s ‘brain’ isn’t functioning correctly, it can create symptoms that mimic a dozen other failures.
Common Symptoms of a Failing ECM
- ✔ Persistent Check Engine Light (CEL) that won’t clear or returns immediately.
- ✔ Engine stalling or shutting off unexpectedly while driving.
- ✔ Noticeable decrease in fuel economy.
- ✔ Engine misfires, rough idling, or hesitation during acceleration.
- ✔ Complete no-start condition where the engine cranks but won’t turn over.
- ✔ Automatic transmission shifting erratically or harshly.
- ✔ Inability for diagnostic scan tools to communicate with the module.
Solving Your Engine Problems with a Programmed 2014-2016 Caprice ECM
Replacing your vehicle’s ECM can seem daunting, but our service simplifies the process. By providing us with your VIN during checkout, you ensure that the replacement 2014-2016 Caprice ECM you receive is a perfect match for your vehicle’s specific configuration. This includes the engine and transmission calibration, anti-theft system parameters, and any other vehicle-specific options. This attention to detail is what separates a simple part from a true, effective repair solution.
This module is a direct-fit replacement for a wide array of GM vehicles, including the Chevrolet Camaro, Malibu, Equinox, Impala, Traverse; Buick Enclave, LaCrosse, Regal; GMC Acadia, Terrain; and Cadillac ATS, CTS, SRX, and XTS from various model years. Please verify the part number and consult the detailed fitment list to confirm compatibility with your exact model and options.
Frequently Asked Questions
Do I need to do any programming myself?
No. We handle all the programming for you. This ECM will arrive flashed with the latest GM software updates and coded specifically to the VIN you provide. This makes the installation process much simpler.
What is a security relearn procedure?
For many GM vehicles, a security relearn (also known as a key relearn or anti-theft relearn) is a simple procedure required to sync the new ECM with your vehicle’s existing keys and anti-theft system. It typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating the cycle two more times. Specific instructions for your vehicle can be easily found online or in a service manual.
Is this a brand new part?
No, this is a high-quality, fully functional used ECM sourced from a salvaged vehicle. Each unit is thoroughly inspected and tested to ensure it meets operational standards before being programmed and shipped.
How do I provide my VIN?
After you complete your purchase, please send us a message with your 17-digit Vehicle Identification Number (VIN). We cannot program and ship your part without it. You can typically find your VIN on your vehicle’s dashboard (visible through the windshield) or on your insurance/registration documents.
Will this part fit vehicles other than the Caprice?
Yes, absolutely. This ECM is compatible with a wide range of GM cars, trucks, and SUVs, including models like the Chevy Equinox, GMC Terrain, Cadillac SRX, and Buick LaCrosse. Please refer to the detailed compatibility list on this page to ensure it matches your specific year, make, and model.