2001 Mitsubishi Eclipse air conditioner malfunction?

Hi, I have an issue with my ac/heater. The blower fans for the heater only work on 4, the highest setting, when i put it on 1,2,or 3 the fan doesnt work, but when on 4 or high, it does. Also when I try and use the A/C the green a/c indicator light on my switch comes on on 1,2 , and 3 but the ac fan doesnt blow. when I put it on 4, the a/c light goes out and it just blows regular air..Please help!!