My vent is only staying on Face then and wont change to feet or Defrost. I can't push the AC button on the unit or the back of the window defroster. I cant change the *** from hot to cold ether. But i can turn the fan off and on. I also cant turn on my back window wiper. Any help? Is it just broken in the control head or do you think a fuse is blown because I fixed Number 25 on the inside control panel because if was blown but I still didn't work .