A/C air only blows out of defroster

[slimjv]

I cannot figure out how to fix this problem. The air only blows out of the defroster no matter what I do. The air for the back seat vents works as advertised. I suspect a vacuum problem but cannot find any problems with the lines. Is there any systematic steps to follow to figure out what happened? The Ford dealer here want $100 just to diagnose the problem--the real charges start after that.

Thanks
Slim

 

[racebronco2]

i have an 2000 x and i have the same problem ... but i noticed that if a/c in in the on position when i start it it will blow thru the dash vents ... but if i turn on the a/c after i start the x then it only blows out of the defroster ... i had the same problem with my old aerostar and i was told that it was probably the a/c heater control, and it would cost about 300.00 for the aerostar .... so i am just dealing with the problem ....don't want to pay in excess of 500.0 or so .... but if anyone know how to diagnos this problem we would surely like to know