I just bought a 03 Dodge Caravan Sport. I was driving down the road and I heard a loud squealing noise and then the a/c starting blowing warm air. I tried to add freon but it said warning like it was full or something. Does anyone have any idea what it could be before I take it for someone to look at?

 

try adjusting the dash temp. controls a few times. i don't know why but on occasion mine blows hot, then remembers it's supposed to go by the temp I set.

As for the squeal, is it a fan squeal? Perhaps your fan motor bearings are going.