Sony MVC FD85 won't turn on.

There are some micro fuses on these units. They are hard soldered onto the board and are surface mount devices. They are usually marked F301, 302 etc ( from my memory) if you examine the board and interior of the case there is a warning notice to replace with the exact same type and a small arrow pointing to their location.
The mavica often has a thin sheet of clear plastic covering the power board