Is Your Cadillac or Buick Running Rough?
If your 2004-2007 Cadillac CTS, SRX, or a compatible Buick model like the Allure, LaCrosse, or Rendezvous is suffering from mysterious electrical gremlins, poor engine performance, or a persistent Check Engine Light, the root cause is often a failing Engine Control Module (ECM). The ECM is the brain of your vehicle, managing everything from fuel injection and ignition timing to transmission shifting. When it starts to fail, it can create a cascade of frustrating and difficult-to-diagnose problems. Don’t let a faulty computer keep you off the road. This pre-programmed ECM is the reliable, straightforward solution to restore your vehicle’s factory performance and dependability.
From the Diagnostic Bay
We once had a 2006 Cadillac SRX come into the shop with an intermittent no-start condition and a laundry list of seemingly unrelated trouble codes. The owner had already replaced the battery, alternator, and a couple of sensors with no luck. After hours of chasing wires, we focused on the ECM. On the surface, it looked fine, but a bench test revealed an internal short that would only appear when the module heated up. We installed a pre-programmed replacement ECM, performed the security relearn, and the SRX fired up instantly. All the ghost codes vanished. It’s a classic case where the central component was the culprit, masquerading as multiple smaller issues.
Common Symptoms of a Failing ECM
- ✔ Check Engine Light is on with various, often inconsistent, communication or sensor codes.
- ✔ Engine stalling, misfiring, or running rough for no apparent reason.
- ✔ A complete no-start condition where the engine cranks but will not fire.
- ✔ Noticeable decrease in fuel economy and overall engine power.
- ✔ Problems with the automatic transmission, such as harsh or erratic shifting.
- ✔ Inability to communicate with the ECM using a standard diagnostic scan tool.
The Direct Solution: A VIN-Programmed 2004-2007 CTS ECM
This isn’t just a part in a box; it’s a complete solution. We take a quality, tested ECM and flash it with the latest official GM software updates specific to your vehicle’s Vehicle Identification Number (VIN). This critical step ensures that the computer has the correct calibration for your engine, transmission, and factory options. By programming it before shipment, we eliminate the need for an expensive trip to the dealership for programming. This makes the replacement process as simple as possible, getting you back on the road faster.
This unit is a direct replacement for several service numbers, including 12581144, 12588472, 12592124, and 19260507. Please verify your part number or consult our fitment list to ensure compatibility.
Installation and Fitment
This ECM is designed to fit the following vehicles:
- Cadillac CTS: 2004-2007 (Base models)
- Cadillac SRX: 2004-2006 (3.6L models)
- Buick Allure: 2005-2008 (3.6L models)
- Buick LaCrosse: 2005-2008 (3.6L models)
- Buick Rendezvous: 2004-2006 (3.6L models)
While the module is programmed for your VIN, most GM vehicles of this era require a security relearn procedure after installation. This process syncs the new ECM with your vehicle’s anti-theft system and keys. It is a simple procedure that can typically be done without special tools and takes about 30 minutes. Instructions are widely available online or in service manuals.
Frequently Asked Questions
Do I need to send you my old ECM?
No, there is no core charge or need to send in your old part. This is a direct purchase.
What happens after I place my order?
After you purchase the ECM, you must provide us with your vehicle’s 17-digit VIN. We cannot program and ship the module without it. Please send it via email or in the order notes.
Is this a new part?
No, this is a fully tested, used ECM sourced from a salvaged vehicle. Each unit is inspected and verified to be in good working condition before being programmed and shipped.
Will this ECM fix my vehicle’s problem?
This part will correct issues directly caused by a faulty ECM. It is crucial to have your vehicle properly diagnosed by a professional mechanic to ensure the ECM is the true source of the problem before ordering.
What is the security relearn procedure?
It’s a process that allows your vehicle’s anti-theft system to recognize the replacement ECM. It typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’, and repeating this cycle three times. Specific instructions can be easily found for your model.