Restore Peak Performance to Your Buick Lucerne
Is your 2009, 2010, or 2011 Buick Lucerne suffering from frustrating and unpredictable engine problems? The Engine Control Module (ECM), often called the vehicle’s main computer, is the central command for all critical powertrain functions. It meticulously manages everything from fuel injection and ignition timing to transmission shifting and emissions control. When it begins to fail, it can cause a cascade of issues that are often difficult to diagnose, leading to poor performance, reduced fuel economy, and even a vehicle that won’t start. This replacement ECM is the definitive solution to restore your vehicle’s original performance and reliability.
From the Diagnostic Bay
We had a 2010 Buick Lucerne with the 3.9L V6 come into the shop with a persistent, random misfire on cylinder 3 (P0303) and a complaint of harsh shifting. The owner had already spent hundreds replacing the spark plug, ignition coil, and fuel injector for that cylinder, but the problem remained. After hooking up our diagnostic scanner and monitoring live data, we noticed the injector pulse width for cylinder 3 was erratic. All wiring checked out perfectly. The root cause wasn’t a mechanical part; it was a failing injector driver inside the original ECM. Installing a VIN-programmed module like this one solved the misfire and the shifting issue in one go, saving the customer from further expensive and unnecessary parts replacements.
Common Symptoms of a Failing ECM
A faulty engine computer can manifest in numerous ways. If you’re experiencing any of the following, it may be time to replace your ECM:
- ✔ Persistent Check Engine Light (CEL) that won’t clear, or illuminates intermittently.
- ✔ Engine stalling, stumbling, or hesitating during acceleration.
- ✔ Noticeable decrease in fuel efficiency for no apparent reason.
- ✔ Rough idling or inconsistent engine RPMs.
- ✔ Hard starting or a complete no-start condition where the engine cranks but won’t fire.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Loss of communication with the OBD-II port, making diagnostics impossible.
- ✔ Specific diagnostic trouble codes (DTCs) pointing to internal module failure.
Why this 2009-2011 Lucerne ECM is a Versatile Solution
This isn’t just a replacement part; it’s a complete, ready-to-install solution. We take the guesswork and hassle out of the repair process. When you order, you simply provide us with your vehicle’s 17-digit Vehicle Identification Number (VIN). Our technicians then flash the module with the latest, most stable software updates directly from GM. This ensures perfect compatibility with your vehicle’s specific configuration and options. This module, service number 12597125, is engineered by GM as a direct replacement for a wide range of original part numbers, including 12611549, 12612397, 12594750, 12629019, and 12635902. Its broad compatibility extends to dozens of other GM models like the Chevrolet Malibu, Impala, Silverado 1500, HHR, Cobalt, and Pontiac G6, making it a proven and reliable component across the GM family.
Plug-and-Play Installation
Because we program the module to your VIN before it leaves our facility, the installation process is straightforward. In most cases, it’s a simple plug-and-play procedure. Simply disconnect the battery, remove the old module (located in the lower part of the air cleaner box on the Lucerne), install the new one, and reconnect the battery. While the module is pre-programmed, some GM vehicles may require a simple security relearn procedure (often called a Passlock or anti-theft relearn) to sync the new ECM with your vehicle’s keys. This procedure can typically be done in your driveway without any special tools and instructions are widely available.
Frequently Asked Questions
Do I need to have this ECM programmed by a dealer?
No. We handle all the programming for you before we ship the part. Simply provide your vehicle’s 17-digit VIN during checkout, and we will flash the module with the latest GM software specific to your car. This saves you a trip to the dealership and expensive programming fees.
Where is the ECM located on my 2009-2011 Buick Lucerne?
On the Buick Lucerne with the 3.9L engine, the Engine Control Module is typically found attached to the lower part of the air cleaner filter box in the engine compartment.
Is this installation difficult? Can I do it myself?
The physical installation is quite simple for anyone with basic mechanical skills. It involves disconnecting the battery and swapping the module. However, some vehicles may require a security relearn procedure to sync the new ECM with your keys. This is a straightforward process you can often do yourself.
What is the difference between an ECM and a PCM?
The terms are often used interchangeably. ECM stands for Engine Control Module, while PCM stands for Powertrain Control Module. In modern vehicles, a single module (the PCM) typically controls both the engine and the transmission. This part serves that function.
How do I know this part will fit my vehicle?
This module replaces multiple GM service numbers, including 12611549, 12597125, and others listed in the description. By providing your VIN, we guarantee that the programming will match your vehicle’s exact specifications for a perfect fit and function.