AC is stuck on defrost and floor which is default. What needs to be done to get the air blowing thru vents?
I found a similar problem in our database. It seems like the Ford products have a module that can fail. GM products use vacuum tube which fail. You can't win sometimes. http://www.cargurus.com/Cars/Discussion-d362_ds499104
It most likely has a vacuum leak. Only a few times have i seen the control head go bad. you need to take the control head out and see if you have vacuum to it. and if not track down the broken hose
The guys are right, a vacuum hose has popped off or cracked.
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