AC help plz- 1990 acura integra LS

im trying to fix my AC cuz Virginia is starting to get hot. it seems to only give out hot air. all lights and switches work. Also my defroster doesnt work. my front and side window defroster works just not rear. rear switch lights up and wiper works

Your read defrost is controlled, [timer] by the ICU, it is a common problem on older Honda/Acura.

For A/C it is a good bet your refrigerant is low, [leak in system], check the front of the A/C compressor is it turning, [when A/C is on]? 94