I have a 2015 Prius C (made late December 15, I bought it late 2016) and in the past 2 weeks my wife said the Entune restarted (blue screen with a progress bar) and all the warning lights came on 2 different times. Wouldn't start until everything rebooted. Today got a call that car completely dead after coming out of the grocery store with baby and a full cart. No lights or anything. Rushed down and hooked up to the under hood jump point, nothing, no power. Pulled rear seat access panel to try to jump there and the little nut that held the positive tight was loose. Finger tightened it and no jump needed. So I guess that is what caused the reboots was a loose nut. Maybe dealer had to replace battery in new car since it sat so long? Anyways I am happy to have an obvious solution to the problem. If you have any bugs check that the 12v battery connection is nice and snug!