Multi Function Display /MIS Screen Doesn't Work | PriusChat This was a good hit when searching for "MFD stopped responding"
There are enough reports on here of that happening, but no one is really sure why. It could have to do with the electronics becoming cooked in the sun, under that huge windscreen. A unit from a salvage yard is about the best you can do. It is a plug and play unit, so possible to DIY. And the windshield reflector sold on PC is worthwhile, if you don't use one.
It's "DIY" if you have many free days available and no need to drive the car during those days while all the various dash components are strewn hither and yon to access the display. That whole dash assembly is one big Rube Goldberg joke on us. Do LOTS of research including photos and exploded view drawings before beginning that extended operation.
