Jeep Repair: 1999 Jeep GCL HVAC, vac line, climate control

Question
My wife's Jeep has an A/C issue.  When you turn the climate control selector air only comes through the defroster vents.  The air will turn off, but will only blow through the defroster even when you select any of the other options.  What may cause this and is this something one can fix at home.

Answer
look under the hood  and I take it u have a 4.0L engine =)
On the driver side there is the manifold look where the brake lines are at and u will see a vac line that has come off U might haft to cut part of the tube so that it will stay on. They just expand with all the heat and cooling down so they just pop off. Easy fix .