Ac Selector switch that chooses diferent modes such as defrost, which vents air comes out of, does not work. Air only blows from defrost vents. When I recently got the car(used) and it was doing this nor did it cool. I had the ac system charged and noted the selector switch started working and the system was cooling. I don't know if charging the system actually had anything to do with or not. Also the fan speed selector switch only worked on high. I changed the blower resistor and fixed that issue. Now its back to doing the same thing with air only coming from defrost vents and not cooling, So don't know if the pressure has dropped and this is some kind of default action secondary to the low pressure or if there are other issues in play here. The ac clutch does not enagage. Any info is appreciated!