I went into an underground parking lot, and I lost satellite signal - like usual. However, when I came out, the power to the stereo was gone. I don't think it's a fuse issue because it still reads "Stereo System Designed by Sony" and the temperature still shows. But, none of the features work. I tried going to CD and AM/FM, but I get no sound at all. I was about to detach a battery lead, but I wanted to see if anyone else had an idea. There are always concerns about memory. It's a 2009 F-150.