there is a switch that is put on these a/c compressor systems that turn off the compressor so the system does not run when you have no freon in it... its called the cycling switch..its located on top of the accumulator, a small tank about 4 in. wide and about 8 in. high... on my 96 V-6 engine its located right in front of the battery.. you got to take the battery out to get to it...you then take the wire harness off the cycling switch that is screwed on top of the accumulator tank... then take a small piece of wire and jump the harness.... the compressor should then come on... if so then you know if you have a full charge of freon that it must be the switch is bad.... go to auto zone or advanced auto parts and get a new one and take off the old one(unscrew it from the top of the accum. tank and put the new one on.... when taking off the old one and putting on the new one you got to do it in a hurry as not to loose any freon...some will come out but if you work quick it will stop flowing... just like a bicycle tire valve....
the last one i bought was about $25 or so for a taurus....
hope this helps.
