Is my computer messed up? HELP!!

I have an 02 Jeep Liberty. It's been great until the last few days. Last week my radio stopped working. Sometimes it will come on when I start up; sometimes it will not. The clock flashes on and off. Everyone told me that it was just a blown fuse, or loose wire. Then today my interior lights started flashing on and off. Everything else is working fine. I've had no problems with any of my guages. I need to know if this is my computer messing up, or if it's just a simple wire/ fuse problem. The local dealership told me they'd "diagnose" it for $100. I can't help but think that the problem is too simple to spend that kind of money. Am I wrong? HELP!!

I am now having the same problem it is a fuse that is blowing, but we have not found the problem as to why. If you have figured it out please let me know