2002 Grand Cherokee air vent control issue

I have 2002 GC and I am curently have a problem with my air vent
control. Currently, all air (AC or heat) comes through the defrost
vents on the dash. None of the other locations work.

Has anyone had similar problems. I called a dealer and they said that
they have seen this problem before and it will require a lot of labor
(labor = $$$) because the piece they need to replace is behind the
dash. I was hoping that the issue is not mechanical but simply
replacing the control behind the knob (maybe the connections are
shot??)

I am thinking of replacing if possible the switch and then go down the
road of replacing the valve or whatever that channels the airflow if
that does not work


Thanks in advance
Steve

 

if u have a 4.0 litre engine look under the hood for a vac supply line
that falls off the nipple on the intake manifold. hose swells out from
oil and won't fit tight