Restore Your Vehicle’s Performance and Reliability
Is your Buick LaCrosse, Cadillac CTS, or other compatible GM vehicle suffering from frustrating engine issues? Stalling, rough idling, a persistent check engine light, or a no-start condition can often be traced back to a failing Engine Control Module (ECM). As a technician with over two decades of experience, I’ve seen how a faulty ECM can disrupt everything from fuel delivery to transmission shifting. This isn’t just an inconvenience; it’s a critical failure that needs a reliable solution.
This listing is for a thoroughly tested, used OEM Engine Control Module, part number 12592124. The real value here is our professional programming service. Before we ship the part, we flash it with the latest GM-approved software updates, specifically matched to your vehicle’s VIN. This means you receive a part that is ready for installation, saving you the significant time and expense of a trip to the dealership for programming. It’s the most direct path to getting your vehicle running correctly again.
From the Diagnostic Bay: The Case of the Intermittent Stall
I remember a 2007 LaCrosse with the 3.6L V6 that came into my shop. The owner was frustrated with random stalling at traffic lights and a check engine light that would come and go. His scanner showed a P0606 code (ECM/PCM Processor Fault). After verifying the power and ground circuits to the ECM were solid—a crucial first step—we confirmed the module itself was failing internally. Instead of a costly new unit, we sourced a tested used module like this one, programmed it to his VIN, and performed the security relearn. The car ran perfectly, and the customer saved hundreds. This is a common story for these vehicles, and this part is the proven fix.
Is Your GM Vehicle Showing These ECM Failure Signs?
A failing ECM can cause a wide range of symptoms. If you’re experiencing any of the following, a faulty engine computer is a likely culprit. Look out for these common indicators:
- ✔ Persistent Check Engine Light (CEL)
- ✔ Diagnostic Trouble Codes (DTCs) such as P0601, P0602, P0606, or U0100
- ✔ Engine stalling or shutting off unexpectedly
- ✔ No-start or hard-starting conditions
- ✔ Noticeable drop in fuel economy
- ✔ Poor engine performance, hesitation, or misfires
- ✔ Erratic automatic transmission shifting
A Straightforward Guide to Installation
Replacing the ECM on these vehicles is a manageable job for a confident DIYer or any professional mechanic. Our pre-programming service handles the most complex part for you. Follow these general steps to get your vehicle back on the road.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 15 minutes for the system capacitors to discharge.
- Locate the ECM: On the LaCrosse and Allure, the ECM is typically found in the lower air cleaner housing. On other models like the CTS or SRX, it’s often in the engine compartment. Consult a service manual for your specific vehicle if you’re unsure.
- Disconnect Connectors: Carefully release the locking tabs on the electrical harness connectors and pull them straight out from the module. Do not force them. Inspect the pins for any corrosion or damage.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep the hardware, as you will need it to install the new unit.
- Install the New ECM: Mount your new, pre-programmed ECM in place and secure it with the original hardware.
- Reconnect Everything: Firmly plug the electrical connectors back into the new module until they click into place. Reconnect the negative battery terminal.
- Perform Security Relearn: You will likely need to perform a security relearn procedure (often called a Passlock or anti-theft relearn). This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’, and repeating this cycle three times. This allows your vehicle’s anti-theft system to recognize the new ECM.
Verified Vehicle Compatibility List
This module is a direct replacement for service numbers 12581144, 12588472, 12592124, and 19260507. Please verify your part number or match your vehicle from the list below to ensure proper fitment.
ALLURE 06-08 Electronic Control Module; (lower air cleaner housing), 3.6L
CTS 04 Electronic Control Module; (RH engine compartment), Base, ID 19260507
CTS 04-06 Electronic Control Module; (RH engine compartment), Base, ID 12592124
CTS 07 Electronic Control Module; (RH engine compartment), Base
LACROSSE 05 Electronic Control Module; 3.6L
LACROSSE 06-08 Electronic Control Module; (lower air cleaner housing), 3.6L
RENDEZVOUS 04-05 Electronic Control Module; (LH engine compartment), ID 19260507
RENDEZVOUS 06 Electronic Control Module; 3.6L
SRX 04-06 Electronic Control Module; (RH front engine compartment), (3.6L)
Frequently Asked Questions
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) is essential for us to program the ECM with the correct software and calibrations for your specific vehicle’s engine, transmission, and options. This ensures seamless integration and proper function without a trip to the dealer.
Is this a new part?
No, this is a high-quality, tested used part sourced from a salvaged vehicle. Each unit is inspected and verified to be fully functional before being programmed and shipped. This provides a reliable, cost-effective alternative to a new dealership part.
What is the security relearn procedure?
The security relearn syncs the new ECM with your vehicle’s anti-theft system. For most GM vehicles of this era, it involves a simple ’10-minute key-on’ procedure that you can do yourself. We can provide general instructions upon request.
Will this fix my check engine light?
If your check engine light is caused by an internal ECM failure (like codes P0601-P0606), this part is the correct solution. However, you should always ensure other potential issues (wiring, sensors, etc.) have been ruled out for a complete and accurate repair.
Do I need any special tools to install this?
For most applications, you will only need basic hand tools like a socket set and screwdrivers to access and replace the module. No special programming tools are required since we handle that for you.