A/C control Head

[Chuck Pierce]

In the last couple weeks my A/C control head has started to not want to 
change to different modes. It gets stuck in the Economy mode and I can 
not turn it off or move to a different mode
or   I can put it into the auto mode and then can only be switched to 
the defrost mode. In either episode it will not allow me to just turn it 
off. Then later at some arbitrary time the head will allow me to turn 
off the system.
Can the control head be pulled apart to clean contacts inside the 
control head? Would that be where the challenge comes from?

Thanks
Chuck Pierce
91 200tq 20v Avant