Senior lady here - I had a new battery installed and the radio/display won’t turn off. The radio fuse was removed as a temporary solution but the battery was dead after sitting for a day. Any ideas and solutions!!!

The battery replacement should have no effect on the radio staying on or off. Maybe its just councidence that your radio broke at the same
time.

Is it a stock stereo or aftermarket?

thanks for your input! It is a stock stereo. I read somewhere about a code???
But more problems today so more questions - windshield defrost fan stays on and no rear defrost (I’m guessing the radio fuse also controls that)
More to follow in a day or two on what else. Argh!
update:
ok, the ‘audio fuse’ controls whole navigation display which includes rear defrost but windshield defrost fan stays on when fuse is removed

I'd disconnect/connect the battery again.

I remember on my car my blower blower fan would stay on if I had the climate control panel disconnected. I thought its pretty strange but I think thats normal behavior. Ive heard it from a fee others as well.

Thats probably why your fan stays on with the fuse removed.