Depends. If it's a hardware failure, then no one should go to jail, just like today, if my wheel falls off (through no fault of my own) and I run into a child, I wouldn't expect to go to jail (heck, drivers already get pretty much free rein to run down pedestrians by saying "I didn't see him"). The car manufacturer may have some financial liability if it was a product defect, but again no jail time.

The interesting moral dilemma is what to do if the car decided it was better to run into a pedestrian and protect the driver than to run into a brick wall and protect the pedestrian.

There's no easy answer to that dilemma.

https://www.nature.com/articles/d41586-018-07135-0