I was stopped at a red light, stacked about 10 cars deep. Once the light turned green, I pressed the gas pedal, but the auto start-stop feature malfunctioned and turned the car completely off. I then pressed the button to reactivate the ignition, and pressed the gas pedal again. After moving forward a few car lengths (or more), the computer engaged the emergency brake and clamped down on the wheels. I was then rear-ended at about 15-20mph.