If it is a fuse, it is probably the 20A or 30A “Rad 2” fuse in the under hood fuse box. But there is also a second fuse panel in back of the coin tray to the left of the steering wheel. There may be a radio fuse there as well. You remove (Open then pull up) the coin tray to get to it. The fuse diagram is on the back of the coin tray.
Equally likely is that the always on radio power line that bypasses the ignition switch has come off the radio. On many cars – I’m not sure about this one – it is a separate wire that is not part of the wiring harness for the radio.