2000 saturn the ac comp wont engage. fuse is good freon is good new comp clutch and dryer the comp is not getting power some how. relay is good it was traded with another like one. could it be the ac diode or the high side switch? i dont see a low side switch on this model.

SOURCE: air conditioning

here is a link to your problem and a solution:
http://en.allexperts.com/q/4-Wheel-Drive-2700/2008/5/C-Clutch-engaging.htm

SOURCE: 2003 honda accord air conditioning

replace the black relay between the 2 blue relays in the fuse box. cost about 5 bucks.

SOURCE: air conditioning clutch

check to make sure the a/c system is fully charged, if it is not the system will not turn on, if you need more help get back to me. please rate my fix as i strive to be the best

SOURCE: 2000 Ford Taurus AC compressor not working;

if compressor clutch dont kick in .it has a open in clutch coil.

SOURCE: my ac blows hard, added freon, clutch not turning could it be fus

If the blower is working,it indicates your car blower system is ok.If the freon system is contain the correct amount and still clutch is not turning when the A/C switch is in the on position check the supply for the compressure.If there is supply that means the problem with the A/C compressur clutch coil and apply the repair procediure or replace A/C cpmpressure.If there is no supply Check the fuses,wiring system and A/C system pressure switch.