Programmed 2010-2012 CTS Engine Control Module ECM 12642665

Restore Your Cadillac’s Performance and Reliability

Is your 2010-2012 Cadillac CTS suffering from frustrating, hard-to-diagnose issues? A persistent Check Engine Light, unexplained stalling, rough idling, or a sudden drop in fuel economy are often signs that the very brain of your engine—the Engine Control Module (ECM)—is failing. As a technician with over two decades of experience under the hood, I’ve seen how a faulty ECM can turn a reliable luxury vehicle into a source of constant stress. This isn’t just an inconvenience; it affects your car’s safety, performance, and emissions.

This is your direct-fit, reliable solution. We offer a genuine GM Engine Control Module, part number 12642665, that arrives at your door programmed specifically for your vehicle. Simply provide us with your Vehicle Identification Number (VIN) after purchase, and our experts will flash the module with the latest, most stable software updates from General Motors. This critical step ensures seamless communication between the ECM and all other vehicle systems, restoring the precise engine management your Cadillac was designed for. You get a part that’s ready for installation, saving you from expensive programming fees and long waits at the dealership.

Is Your Vehicle Showing These Symptoms?

A failing ECM can cause a wide range of problems. If you’re experiencing any of the following, your engine computer is the likely culprit. Replacing your 2010-2012 CTS Engine Control Module is the definitive fix.

• ✔ Check Engine Light is on with codes like P0601, P0606, or U0100
• ✔ Engine cranks but refuses to start
• ✔ Unexplained stalling or rough, inconsistent idling
• ✔ Noticeable decrease in fuel efficiency
• ✔ Poor engine performance and hesitation during acceleration
• ✔ Transmission shifting issues or erratic behavior
• ✔ Problems with other vehicle electronics that seem unrelated

A Straightforward Guide to Installation

Installing your new ECM is a manageable task for a confident DIYer or a quick job for any professional mechanic. Following these steps will ensure a smooth process.

1. Safety First: Disconnect the negative terminal from your vehicle’s battery and wait at least 15 minutes to ensure all systems are fully powered down.
2. Locate the ECM: On the 2010-2012 Cadillac CTS, the Engine Control Module is typically located in the engine bay, on the right-hand (passenger) side. It’s a silver metal box with large electrical connectors.
3. Disconnect the Wiring: Carefully release the locking tabs on the electrical harness connectors and pull them straight off the module. Avoid pulling on the wires themselves.
4. Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep the hardware, as you may need it for the new installation.
5. Install the New ECM: Mount your new, pre-programmed module in place and securely tighten the bolts. Reconnect the wiring harnesses, ensuring they click firmly into place.
6. Reconnect the Battery: Reattach the negative battery terminal.
7. Perform Security Relearn: In many GM vehicles, a security relearn procedure (often called a “key-on, key-off” cycle) is required to sync the new ECM with your vehicle’s anti-theft system. This procedure typically takes 10-30 minutes and can be done without special tools. Consult your vehicle’s service information for the exact steps.

Verified Vehicle Compatibility

This module is a direct replacement for part number 12642665 and is compatible with several other GM part numbers, including 12616889, 12630908, 12637106, 12650256, and 12651993. It fits a wide range of vehicles. Please confirm your part number or match your specific model and engine from the list below:

Note: Please match your original part number or vehicle options to ensure correct fitment. If you are unsure, contact us with your VIN before ordering.