Folks I have a 03 Focus ZX5 that I believe the ac button has gone bad? Problem started with the fan stopped blowing on setting 1,2,3 but would blow on 4 (high) but no cold air. The ac button light came on when on 1,2,3 (no air) but would go off on 4 and blow ambient air (not cold). I replaced the blower resistor and now air blows on all settings but ac will not come on. After reading a few other posts I put knob on defrost with temp set at cold and ac is blowing cold air/compressor running but no light on ac button. From what I read means my actual ac button is bad? If that is the issue How do I fix/replace it?