The fan on my climate control only works on settings 3 and 4. For some reason settings 1 and 2 do not do anything. Can someone tell me why?

 

There is electrical plug behind your glove compartment that plugs to a type of resistance device that controls your fan speed, there are like 3 different sized coils that act like resistors to vary the speeds, full power doesn't use has no resistance. Chances are a couple of yours are broken. If you take your glovebox out you should see it, there are 2 screws that hold it in I believe. I don't think that they are very expensive from the dealership either. HTH.

 

He is talking about the blower motor resistor, and that is usually the problem in cases like yours.