I have a 2010 Ford Fusion SE, 4 cyl. My air was doing likewise. Ford dealership said it was temperature control head. If that didn't work, blend doors may be a problem, but only diagnose after temp head replaced. At the same time battery would go dead. Called road service for dead battery. Air blowing hot and cold at same time. Road service said battery ok and alternator ok. Went to auto parts store, battery ok and alternator ok. Went to Ford dealer, battery ok. Alternator ok according to Ford. Battery was under Ford warranty and Ford would not replace battery since test showed ok. For Ford to warrant battery, test sent to Ford. Had disagreement with dealer over price to repair a/c. Told dealer to stop all work. Replaced battery, air working like artic air. Everyone involved dumbfounded. Even sought auto mechanic online. Both said blend doors. Battery will show no problem, but it was the problem for me.