Recently My A/C wouldn't get cold and was stuck on defrost. None of the other settings worked. A few days later it got cold, but still stuck on defrost. Another day the heat was stuck on super hot and coming from defrost. A day or two later it was back to normal. Now it only blows hot from the defrost and no other settings works, with or without a/c button engaged. This is a button control with a digital temp read out instead of a sliding lever. A few months ago we had to replace the battery but this started far too long afterwards. I'm guessing the switch in the dash?? Might I need to reset something? Could it be a vacuum thing? I have a misfire one of the plugs and a bad coil which are all being replace this weekend. I'm in Florida so I have to get it working properly before we get the next hot/muggy spell.