Restore Peak Performance to Your Buick Lucerne
Is your 2009-2011 Buick Lucerne experiencing frustrating issues like stalling, a persistent check engine light, or a complete no-start condition? As a technician with over two decades of experience, I’ve seen these symptoms countless times, and they often point directly to a failing Engine Control Module (ECM). This isn’t just a part; it’s the brain of your vehicle’s engine, responsible for managing everything from fuel mixture and ignition timing to transmission shifting. When it falters, your car’s reliability and performance suffer dramatically.
This replacement ECM, part number 12628911, is the definitive solution. We take the guesswork and hassle out of the repair by programming the module specifically for your vehicle using your VIN. This means it arrives at your door with the latest GM software updates, ready for installation. You get a reliable fix that restores factory performance without the exorbitant costs and scheduling headaches of a dealership visit.
Case Study: A Tricky Diagnosis
A 2010 Lucerne with the 4.6L V8 came into my bay with a problem that was driving the owner crazy. It would randomly stall at stoplights, but not every time. There were no consistent trouble codes, just a history of a generic P0606 (ECM Processor Fault) that would clear itself. We checked fuel pressure, sensors, and wiring—all perfect. On a hunch, I monitored the ECM’s internal processor data on a long test drive. Sure enough, I saw data dropouts just before it would stall. The internal processor was failing intermittently under load. Swapping in a properly programmed 2009-2011 Lucerne Engine Module like this one solved the issue completely. It’s a classic example of how a failing ECM can create ghost-like problems that are hard to pin down without experience.
Is Your Lucerne Showing These Symptoms?
- ✔ Unexplained stalling or engine hesitation.
- ✔ Complete no-start condition where the engine cranks but won’t fire.
- ✔ Check Engine Light is illuminated with codes like P0601, P0602, P0606, or U0100.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Misfires or rough idling that can’t be traced to plugs or coils.
A Straightforward Guide to Installation
- ✔ Safety First: Disconnect the negative terminal from your vehicle’s battery and wait 10 minutes for the system to discharge.
- ✔ Locate the ECM: On the 2009-2011 Lucerne, the ECM is conveniently located in the lower portion of the air cleaner filter box assembly.
- ✔ Remove the Air Box: You will need to unclip and remove the top of the air cleaner box and the air filter to access the module.
- ✔ Disconnect and Remove: Carefully unplug the electrical connectors from the old ECM. Press the release tabs firmly. Once disconnected, unbolt the module from its mounting bracket.
- ✔ Install the New Module: Seat the new, pre-programmed ECM into the mounting bracket and secure it. Reconnect the electrical harnesses, ensuring they click securely into place.
- ✔ Reassemble and Reconnect: Reinstall the air filter and air cleaner box lid. Reconnect the negative battery terminal.
- ✔ Perform Security Relearn: Your vehicle may require a simple key-cycle security relearn procedure. Turn the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds. Repeat this two more times. On the fourth try, the vehicle should start and run normally.
Verified Vehicle Compatibility
This ECM is a direct replacement for service number 12628911 and is also interchangeable with 12636659, 12639300, 1263605, 12628993, 12625453, 12622175, 12630464, and 12678512. It fits a wide range of GM vehicles, including:
LUCERNE 09-11 (lower part of air cleaner box), 4.6L
Cadillac:
CTS 09 (RH front engine compartment), 6.2L
DTS 09-11
SRX 09 (LH engine compartment), 4.6L
STS 09 (LH frame rail), 4.4L or 4.6L
STS 10 (LH frame rail), 4.6L
XLR 09 (RH front engine compartment), ID 12625453 or 12636659
Chevrolet:
COLORADO 09 (RH firewall)
COLORADO 10-12 (RH firewall), 2.9L or 3.7L
CORVETTE 09 (RH engine compartment), ZR1
TRAILBLAZER 09 (LH engine), 6.0L
GMC:
CANYON 09 (RH firewall)
CANYON 10-12 (RH firewall), 2.9L or 3.7L
ENVOY 09 (LH engine), 5.3L
Hummer:
HUMMER H3 09-10 (RH firewall)
Saab:
SAAB 9-7X 09 (LH engine)
Frequently Asked Questions
Frequently Asked Questions
Do I need to program this module?
No. We handle all the programming for you before shipment. Simply provide your vehicle’s 17-digit VIN during checkout, and it will arrive ready to install with the latest GM software.
Where do I find my VIN?
Your VIN can be found on your vehicle’s registration, insurance card, or on a placard on the driver’s side of the dashboard visible through the windshield.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the original ECM (e.g., codes P0601-P0606), this part is the correct fix. It will not fix issues related to other faulty sensors or mechanical problems.
Is this a simple DIY job?
For most individuals with basic mechanical skills, this is a straightforward replacement. The location on the Lucerne is accessible, and our pre-programming service eliminates the most complex step. Just follow our installation guide.
What happens after I install it?
After installation and completing the security relearn procedure, your vehicle should start and run smoothly. We recommend clearing any old fault codes with a standard OBD2 scanner after the repair is complete.