Separately, an incident involving a push-button start in a Lexus in 2009 killed 79-year-old Ernest Codelia Jr. and left his companion, Mary Rivera, brain-damaged.

"It shook me to my core. I was very scared," said John Negron. Now, Rivera can't get around without help from full time nurses. Key fobs allow you to start and stop a car with a push of the button ...