My radio light (display) is out does it need a fuse or bulb?

What is your question?

I am wondering if sitting in extreme heat has anything to do with it. The car normally sits in my garage if I dont drive to work. This happened one time before but the light came on again. I have Sirius/cd/AM/FM,..I also have a subwoofer and amp hooked up done by a specialist. I cant see what channels or the name of the song playing. (No light) Please help me. Thanx