a/c issue's

Hello, i have a 1993 intrepid es with a 3.3 v6 engine, im currently working on my a/c system. For some reason my compressor is not engaging, I have auto climate control and my a/c is on, fan is blowing at full capacity but blowing out warm air:uhoh:. My freon is low but would adding a new charge of freon make my compressor engage or do i need more work done to the system:disappoin? Any and all help/advice would be greatly appreciated.....thank's:)