The short could result in a fire, and it's potentially severe enough for the automaker to advise that owners park affected vehicles outside until they're fixed.
In 2006-2007 Chevrolet Trailblazer, GMC Envoy, and Buick Rainier models—as well as 2005-2007 Saab 9-7X and 2006-2007 Isuzu Ascender models, which were also built by GM—fluid entering the master power-window switch module could cause corrosion and then a short in the circuit board.
The short could cause intermittent malfunction (the windows raising or lowering themselves), or failure, according to GM; or it could result in overheating (a burning smell), smoke, or fire—potentially when the vehicle is not even in use, which is why you should park such vehicles away from the house.
This recall, of 184,611 vehicles in all, builds on one issued last year, and may require those who already brought their vehicle in for that 'fix' to check back in again for this remedy. Last year's recall involved the testing of the module, and the application of a protective coating to the affected pieces if working properly. This year's revised fix has dealerships check the part number of the door module and swap it out for a new one if it's affected.
According to GM spokesman Alan Adler, the dealer bulletin with the revised service procedure will go out to dealers soon, as will customer advisory letters. New parts for the recall won't be available until fall.
In the meantime, owners should check with their dealership to see if their vehicle is affected; or they may call customer service at 800-521-7300 (Buick), 800-222-1020 (Chevrolet), 800-462-8782 (GMC), 800-955-9007 (Saab), or 800-255-6727 (Isuzu).