Is Your Cadillac or GM Vehicle Running Rough?
If your 2008-2009 Cadillac CTS, STS, or another compatible GM vehicle is suffering from perplexing issues like a persistent check engine light, erratic engine behavior, poor fuel economy, or even a no-start condition, the culprit is often a failing Engine Control Module (ECM). The ECM is the central computer of your vehicle, responsible for managing everything from fuel injection and ignition timing to transmission shifting and emissions control. When it begins to fail, it can create a cascade of problems that are frustrating and difficult to diagnose.
Don’t let a faulty computer keep you off the road. This direct-fit Engine Control Module, part number 12605672, is the definitive solution to restore your vehicle’s performance, reliability, and efficiency. The most significant advantage of our service is that we take the guesswork and dealership hassle out of the equation. Before this module ever leaves our facility, it is professionally programmed with the latest official GM software updates, tailored specifically to your vehicle using its unique Vehicle Identification Number (VIN). This ensures a seamless installation process and optimal performance from the moment it’s connected.
From the Diagnostic Bay
We had a 2009 Acadia come into the shop with a bizarre set of symptoms. The owner complained of intermittent stalling at stoplights and a check engine light with codes for random misfires (P0300) and a throttle position sensor fault. We checked the wiring, replaced the throttle body, and even swapped coils, but the problem persisted. After hours of chasing ghosts, we hooked up a scope to the ECM outputs and noticed the 5-volt reference signal was dropping out intermittently. The internal voltage regulator in the original ECM was failing under load. We installed one of our pre-programmed modules, performed a quick crankshaft position relearn, and the vehicle ran perfectly. The customer was thrilled to have their reliable family hauler back, and it was a stark reminder that sometimes the ‘brain’ is the source of all the trouble.
Symptoms of a Failing Engine Control Module
- ✔ Check Engine Light: The most common symptom. The light may be on constantly or flash, often with codes related to sensors, communication errors (U-codes), or processor faults.
- ✔ Poor Engine Performance: You may experience rough idling, hesitation during acceleration, engine misfires, or a noticeable loss of power.
- ✔ Reduced Fuel Economy: A failing ECM can’t properly calculate the air-fuel mixture, leading to the engine running too rich or too lean, drastically impacting your MPG.
- ✔ Intermittent Stalling: The engine may stall for no apparent reason, either while driving or when coming to a stop.
- ✔ No-Start Condition: In severe cases, the ECM may fail to control the fuel pump or ignition system, preventing the vehicle from starting at all.
- ✔ Transmission Shifting Issues: The ECM works with the Transmission Control Module (TCM) to ensure smooth shifts. A faulty ECM can cause harsh shifting, delayed engagement, or getting stuck in one gear.
The Premier Solution: A Programmed 2008-2009 CTS ECM
This isn’t just a replacement part; it’s a comprehensive solution. By providing us with your VIN during checkout, you ensure that the 2008-2009 CTS ECM you receive is loaded with the correct software calibration for your vehicle’s specific configuration, including engine, transmission, and emissions equipment. This process corrects many factory-known software bugs and drivability issues, often resulting in performance that’s better than the original. This plug-and-play approach saves you a costly trip to the dealership for programming.
Simple Installation Process
Once you receive your programmed module, the physical installation is straightforward. For the Cadillac CTS and STS, the module is typically located in the engine compartment on the right-hand (passenger) side. For the GM SUVs like the Acadia and Traverse, it’s often found behind the fan shroud. Simply disconnect the battery, unplug the electrical connectors from the old module, unbolt it, and install the new one in its place. After reconnecting the battery, your vehicle may require a simple security relearn procedure (often called a Passlock or anti-theft relearn), which can typically be done in your driveway without special tools. Instructions for this procedure are widely available online or in your owner’s manual. In some cases, a crankshaft position variation relearn may be needed, which requires a capable scan tool.
Guaranteed Compatibility
This module is a direct replacement for the following part numbers:
- 12623325
- 12628387
- 12605672
- 12630594
- 19300016
It is confirmed to fit the following vehicles with the specified options:
- 2008 Cadillac CTS: Electronic Control Module; (RH front engine compartment), (3.6L), VIN V (8th digit)
- 2009 Cadillac CTS: Electronic Control Module; (RH front engine compartment), 3.6L, VIN V (8th digit)
- 2008 Cadillac STS: Electronic Control Module; (RH engine), 3.6L
- 2009 Cadillac STS: Electronic Control Module; (RH engine), (3.6L)
- 2009 GMC Acadia: Electronic Control Module; (behind fan shroud)
- 2009 Chevrolet Traverse: Electronic Control Module; (behind fan shroud)
- 2009 Saturn Outlook: Electronic Control Module; (behind fan shroud)
- 2009 Buick Enclave: Electronic Control Module; (behind fan shroud)
Restore your vehicle’s brainpower and get it running like new. Order your pre-programmed 2008-2009 CTS ECM today and experience the difference a perfectly matched module makes.
Frequently Asked Questions
Is this ECM ready to install when I receive it?
Yes! This ECM comes fully programmed to your vehicle’s specific VIN with the latest GM software updates. In most cases, it’s a plug-and-play installation, though some vehicles may require a simple anti-theft relearn procedure that you can do at home.
How do I provide my VIN?
After you complete your purchase, you will need to send us your 17-digit Vehicle Identification Number (VIN). We cannot program and ship the module without it. You can typically find your VIN on your driver’s side dashboard (visible through the windshield) or on the driver’s side door jamb sticker.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the ECM, then yes, this part will resolve the issue. However, the check engine light can be triggered by many other components (like a bad sensor or a loose gas cap). It is always best to have the codes read by a professional to confirm the ECM is the likely cause of the problem.
What tools are needed for installation?
Basic hand tools, such as a socket set, are typically all that is required to physically swap the module. No special programming tools are needed from you, as we handle all the programming before shipment.
Do I need to send my old ECM back?
No core charge or return is required for this part. You can keep your old module or dispose of it responsibly.