after reading another thread where the a/c knob cracked i realized this could be a common problem in del sols/civics?mine cracked and wouldnt turn on the a/c or blower motor so i removed it and got some duco cement(this stuff works on most anything,comes in a tube like model glue)put it on the cracked portion inside the crack and hold it together for a couple hours(i used vise grips set to just gently grip it without deforming the part)when dry just push it back on and youll be able to use the a/c again.