Restore Your Vehicle’s Core Command Center
Is your Cadillac CTS, Corvette, or other GM vehicle acting erratically? Experiencing frustrating issues like intermittent stalling, a persistent check engine light, or a complete no-start condition can be a major headache. These are classic 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 firsthand how a faulty ECM can cripple a perfectly good vehicle. This isn’t just a part; it’s the central nervous system for your engine’s performance, fuel economy, and emissions.
This replacement Engine Control Module, part number 12622175, is the definitive solution to get your vehicle running reliably again. What sets this part apart is our professional programming service. Before we ship it, we flash the module with the latest, most stable software updates directly from GM, using your vehicle’s specific VIN. This means it arrives at your door ready for installation, saving you a costly trip to the dealership and eliminating the need for expensive scan tools. Getting a reliable fix for your 2009 CTS Engine Module has never been more straightforward.
From the Diagnostic Bay: The Phantom Stall
I remember a 2009 Cadillac CTS 6.2L that came into my shop with a maddening problem. The owner said it would run perfectly for days, then suddenly stall at a red light without warning. No consistent codes were stored, just a history of random communication faults. We checked fuel pressure, sensors, and wiring harnesses—all were fine. After hours of diagnostics, we connected a scope to the ECM’s power and ground circuits and finally caught it: a momentary internal voltage drop inside the module itself. The processor was briefly failing under load. We replaced it with a VIN-programmed module just like this one, and the phantom stalling vanished for good. It’s a textbook example of how a failing ECM can mimic a dozen other problems, making a quality replacement the only true fix.
Is Your Vehicle Showing These Symptoms?
- âś” Check Engine Light is on with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (ECM/PCM Processor Fault).
- âś” The engine cranks but refuses to start.
- âś” Unexplained drops in fuel economy and poor engine performance.
- âś” Intermittent stalling or rough idling for no apparent reason.
- âś” Automatic transmission shifting erratically or harshly.
- âś” Communication errors with diagnostic scan tools.
A Straightforward Guide to Installation
Replacing your 2009 CTS Engine Module is a manageable job for a confident DIYer. The key is taking your time and being methodical. Always consult a vehicle-specific repair manual if you are unsure about any step.
- Safety First: Disconnect the negative terminal from your vehicle’s battery and wait at least 15 minutes to ensure all capacitors in the system are discharged.
- Locate the ECM: On the 2009 CTS, the ECM is typically found in the engine compartment on the right-hand (passenger) side. Its exact location can vary on other compatible models, so confirm its position on your vehicle.
- Disconnect Connectors: Carefully release the locking tabs on the electrical wiring harnesses and gently pull them straight out from the module. Never force them. Inspect the connectors for any corrosion or damaged pins.
- Remove the Old Module: Unbolt the mounting hardware holding the old ECM in place and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed ECM in the same location and secure it with the original hardware.
- Reconnect and Secure: Firmly plug the wiring harnesses back into the new module until they click into place. Reconnect the negative battery terminal.
- Final Steps: Some vehicles may require a security relearn or crank position sensor relearn procedure after installation, which can often be done without special tools. Turn the key to the ‘ON’ position for 10-15 minutes before attempting to start the engine. This allows other modules to recognize the new ECM.
Verified Vehicle Compatibility
This module is a direct replacement for service number 12622175 and is interchangeable with several other part numbers, including 12636659, 12639300, and 12625453. It is guaranteed to fit the following vehicles and configurations:
CADILLAC DTS 2009-2011
CADILLAC SRX 2009 (4.6L)
CADILLAC STS 2009-2010 (4.4L, 4.6L)
CADILLAC XLR 2009
CHEVROLET COLORADO 2009-2012 (2.9L, 3.7L)
CHEVROLET CORVETTE 2009 (ZR1)
CHEVROLET TRAILBLAZER 2009 (6.0L)
GMC CANYON 2009-2012 (2.9L, 3.7L)
GMC ENVOY 2009 (5.3L)
HUMMER H3 2009-2010 (3.7L)
BUICK LUCERNE 2009-2011 (4.6L)
SAAB 9-7X 2009
A properly functioning 2009 CTS Engine Module is essential for your vehicle’s health. Don’t let a faulty computer keep you off the road. This VIN-programmed unit is the most reliable and efficient way to solve your engine management problems.
Frequently Asked Questions
Do I need to do any programming myself?
No. We handle all the programming before shipment. Simply provide your vehicle’s VIN during checkout, and the module will arrive with the latest GM software, ready for installation.
Is this a direct replacement for my original part?
Yes, this is a direct-fit replacement for the original equipment and is interchangeable with multiple service numbers, including 12636659, 12628993, and 12622175.
Will this fix my check engine light?
If the check engine light is caused by an internal ECM failure (like codes P0601-P0606), this part will resolve the issue. However, you should always confirm the diagnosis, as other failing sensors could also trigger a warning light.
What is a VIN and where do I find it?
The VIN is your 17-digit Vehicle Identification Number. You can find it on your vehicle’s registration, insurance card, or on the driver’s side dashboard viewable through the windshield.
Do I need to perform a security relearn procedure?
On many GM vehicles, a simple security relearn is required. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. This allows the anti-theft system to sync with the new ECM.