Audio won’t turn on and buttons don’t respond..

Write all the codes down and get as much info as possible from the car in its current state... Then disconnect the 12volt for 10 minutes and either problem ends or the car repair journey begins...

 

sounds like a new mfd required id p/c's advice doesn't work.
should be cheap on eBay.

 

Depends on your definition of "cheap"! At least some are down to $100 now (last time I looked, $200 was the bottom!) A Pick'N'Pull is a better bet (cheaper and usually a money-back guarantee.)
The early years Prius MFD (Multi-Function Display) have a know flaw, and a lot were replaced by Toyota years ago. Symptoms were loss of communication (Audio and Climate) and eventually "freezing up" and running VERY SLOWLY. Usually a reset will fix it, but only temporarily (but, "temporarily" might be a day, a month, or a year!). So, @PriusCamper has really good advice, disconnect the regular battery in the back for 10 minutes (it will probably wipe all settings in the radio), and hope for the best!

 

agreed, but aren't new ones big bucks?

 

I get your point! $100-$200 is VERY cheap compared to $5,900!

 

My factory stereo unit died when I put a library CD with anti-theft tape on it.
The unit, which also had Navigation on it, couldn't eject the CD. And it kept trying for months until the unit burned out.
Dealer Service department said it would cost over $2k to replace. Went without a radio for a few months. Eventually had to drop about $800 to buy an after market stereo unit with installation.