General Motors Co. is undergoing a massive recall of 1.5 million 2006-2009 model year vehicles to disable a heated washer fluid system that poses a potential fire risk. The recall, slated to begin on June 14, covers 18 models from the Buick, Cadillac, Chevrolet, GMC, Hummer and Saturn brands.The heated washer fluid system was the subject of an August 2008 recall that included many of the