In affected vehicles—certain 2011 Buick LaCrosse and Cadillac SRX models—the climate-control module might completely disable the ability to adjust climate settings. In the event of a failure, the defogging and defrosting functions might not be available when they're needed, and could potentially contribute to an accident.
The issue is with software—not the components themselves—so dealerships will perform a software update and recalibration on the affected modules. The update itself will only take about 25 minutes, though the dealership will need to have your vehicle a little longer than that.
There have been no incidents or accidents attributed to the issue so far, and GM found the flaw in an internal test when working on a new version of the flawed software.
The recall effort is expected to begin this Friday, March 11, 2011. Owners with any questions may contact Buick at 866-608-8080, Cadillac at 866-982-2339, or check the GM Owner Center.