2001 caravan a/c blower only blows to defrost

My cousin's Caravan is only blowing air to the windshield. Sounds to me like a vacum problem but I may be wrong.
Any advice
Thanks

Believe its all electrically driven. You may just need to recalibrate the system. Try one of these procedures: http://www.allpar.com/fix/codes-climate.html

If your A/C isn't working, get it fixed before you try a calibration or you may have constant blinking lights on the HVAC control panel until it is.