This defect can affect the safe operation of the airbag system. Until this recall is performed, customers should remove all items from their key rings, leaving only the ignition key. The key fob (if applicable), should also be removed from the key ring. General Motors LLC (GM) notified the agency on February 10, 2014 that they are recalling 619,122 model year 2005-2007 Chevrolet Cobalt, and 2007 Pontiac G5 vehicles. On February 25, 2014, GM increased the recall to include an additional 748,024 model year 2006-2007 Chevrolet HHR and Pontiac Solstice vehicles and 2003-2007 Saturn Ion vehicles and 2007 Saturn Sky vehicles. In these models, the weight on the key ring and/or road conditions or some other jarring event may cause the ignition switch to move out of the run position, turning off the engine. On March 27, 2014, GM notified the agency that the defective ignition switches may have been used as service replacement parts on other vehicles, and as a result GM will be recalling certain model year 2008-2010 Chevrolet Cobalt, Saturn Sky, and Pontiac G5 and Solstice, and 2008-2011 Chevrolet HHR vehicles. The part numbers for the service parts are 10392423 (a/k/a ACDelco D1461F), 10392737, 15857948, 15854953, 15896640, and 25846762. This expansion represents an additional 823,788 vehicles.