Dead KitchenAid Wall Oven

My wall oven died after I’d used it and turned it off; it was off for about five minutes when it died. The breaker is fine. The door opens, but no display or sounds. I’ve checked around and it seems it could be one of several things wrong–thermal fuse, terminal block… Apart from calling a tech, is there a way to know exactly what’s wrong so we may repair it ourselves? All suggestions are welcome!