Restore Your Buick’s Performance and Reliability
As a technician with over two decades of experience under the hood, I’ve seen firsthand the frustration a failing Engine Control Module (ECM) can cause. Your 2010-2011 Buick LaCrosse might be experiencing perplexing issues like stalling at intersections, erratic idling, a persistent Check Engine light, or a sudden drop in fuel economy. These aren’t just annoyances; they’re signs that the very brain of your engine is struggling. This isn’t the time for guesswork. You need a dependable solution that gets you back on the road with confidence.
This is a direct-fit replacement Engine Control Module for your vehicle, identified by part number 12642665 and its equivalents. The biggest hurdle with ECM replacement has always been the expensive and time-consuming programming required at a dealership. We eliminate that step entirely. Before this module ships, we will flash it with the latest official GM software, precisely matched to your vehicle’s unique Vehicle Identification Number (VIN). This ensures seamless integration and optimal performance right out of the box, restoring the smooth operation and efficiency you expect from your LaCrosse.
Case Study: A Tricky Diagnosis
I remember a 2011 LaCrosse that came into my bay with a complaint of intermittent no-start and random stalling, but with no consistent trouble codes. The owner had already replaced the battery and checked the fuel pump. After running a full diagnostic, I noticed the data stream from the ECM would occasionally drop out completely. This pointed to an internal failure within the module itself, likely a cracked solder joint on the main board from years of heat cycles. We replaced it with a VIN-programmed module like this one. The car started every time, the stalling vanished, and the owner was thrilled to have their reliable car back without a massive dealership bill. This is a common failure mode, and a pre-programmed module is the most efficient fix.
Is Your LaCrosse Showing These Symptoms?
A failing ECM can manifest in various ways. If you’re noticing any of the following, this module is the likely solution:
- ✔ Persistent Check Engine Light (CEL)
- ✔ Engine stalling, stumbling, or hesitating
- ✔ No-start or hard-starting conditions
- ✔ Noticeable decrease in fuel efficiency
- ✔ Poor engine performance or lack of power
- ✔ Transmission shifting problems or harsh shifts
- ✔ Stored diagnostic trouble codes (DTCs) such as P0601, P0606, or U0100
A Straightforward Guide to Installation
Replacing the 2010-2011 LaCrosse ECM is a manageable task for a confident DIYer. With our pre-programming, you skip the hardest part. Follow these general steps to get the job done:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait a few minutes to ensure the system is fully discharged.
- Locate the ECM: On the 2010-2011 LaCrosse, the ECM is typically found in the left-hand (driver’s side) of the engine compartment. It’s a metal box with several large electrical connectors.
- Disconnect and Remove: Carefully unclip and disconnect the wiring harnesses from the old module. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed ECM into place. Securely reconnect the wiring harnesses, ensuring each clip clicks firmly into place.
- Reconnect Battery: Reattach the negative battery terminal and tighten it securely.
- Perform Security Relearn: Your vehicle may require a simple key-cycle security relearn procedure to recognize the new ECM. This typically involves turning the key to the ‘ON’ position for 10-15 minutes. Consult your owner’s manual or a reliable online resource for the specific procedure for your vehicle.
Verified Vehicle Compatibility
This module is a guaranteed fit for a wide range of GM vehicles. Please verify your part number or match your vehicle, year, and engine option from the list below. This module is a direct replacement for part numbers: 12616889, 12630908, 12637106, 12642665, 12650256, 12651993.
ALLURE 10 (2.4L, 3.0L)
LACROSSE 10 (3.0L)
LACROSSE 10-11 (2.4L)
REGAL 11
Cadillac:
CTS 10-12 (3.0L)
CTS 12 (3.6L)
SRX 10-11 (3.0L)
Chevrolet:
CAMARO 12 (3.6L)
CAPTIVA SPORT 12
EQUINOX 10-11
IMPALA 12
ORLANDO 12-13
GMC:
TERRAIN 10-11
Saab:
SAAB 9-5 10-11 (2.0L)
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) is essential. We use it to load the exact, correct GM factory software for your car’s specific options and systems. This ensures the module works perfectly upon installation without needing a trip to the dealer.
Is this a simple plug-and-play installation?
Yes, because we program the module to your VIN, it is a plug-and-play part. However, most GM vehicles will require a simple security relearn procedure (often a key cycle) to sync the new ECM with your vehicle’s anti-theft system. This procedure does not require special tools.
Will this fix my specific problem?
This module corrects issues directly caused by a faulty ECM, such as internal processor faults (P0606) or memory errors (P0601). While it solves many common problems, always ensure your vehicle has been properly diagnosed by a professional or that you’ve ruled out other potential causes like bad sensors or wiring.
Does this part come with a warranty?
Yes, all of our electronic modules come with a warranty that protects you against defects. Please see the warranty tab on this listing for complete details and peace of mind.
Are any other part numbers compatible?
Yes, this ECM, 12642665, also directly replaces several other part numbers, including 12616889, 12630908, 12637106, 12650256, and 12651993. If your original module has one of these numbers, this part is a correct replacement.