It doesn't exactly control everything, there are many posts on this forum that detail what it controls, and
www.impalahq.com has a good explanation under the How-To section, about 3/4 of the way down on the left.
It sounds like you may have a loose connection somewhere. Your car isn't going to blow up, your airbag will not deploy "just because", your ABS will still work and frogs won't fall from the sky (well, OK, maybe) just because the radio isn't working properly. I mention it because some people believe that the radio controls all of these things (not the frogs).
If you can take the time, pull your dash, remove the 3 or 4 screws holding your radio in, and check the connection on the back. Also check the antenna to see if it is coming loose.
Jim