Okay, I am going to assume the fan is a 2-pin fan, If you have a multimeter you should check the connection on the board for the fan first, if it's getting proper voltage then probably a dead fan, Also check on the fan for the amount of voltage it needs, if it isn't getting voltage then you probably have bigger problems. If it is a 3 or more-pin fan then probably a feature since most of the fans I have usually get a signal to turn on if their 3 or more pin. For the overheating, I can't give a good answer but the first thing that jumps to mind for me is that there is a short circuit somewhere on the board that is causing it to get hot, or it could be something else like poor ventilation.