Last spring, I had loaned my truck to a friend, and after a week he returned it to me, statint that my radio was going bad. Sure enough, the radio, and all of the electronics associated with it, clock, CD player and even my remote key fob died. My first assumption was a fuse, but when I tried to pull it, it had a yellow cap on it, that prevents me from pulling it. Took it down to auto zone, and they put it on their machine, but they couldn't get any reading, so I'm kinda stuck. Don't know how to get the fuse out, and still don't know whether that is even the problem. Any suggestions?