Ford Repair: air cond clutch, air cond, electrical portion

Question
ive owned a 89lincoln town car since new,two yrs ago i had the A/C  overhauled ,on trying the A/C this yr i noticed the clutch wasnt kicking in , result no A/C,. i checked my fuse found it was ok , so my qestion is " could it be  a "relay" problem,? also where would i locate the relay on my car ?"i owe it to myself to check this out be
vince danagherfore i put it in the shop for repair  thank you  PS the freon was replaced with  this  new enviromently freindy  stuff at time of overhaul  

Answer
Vince, the A/C compressor may not come on if the freon level is low... put gauges on the system and see if there is about 80-100 psi available.  
The cycling switch will prevent compressor engagement if the pressure drops to about 24-28, and allows it to come back on when it climbs to about 40-45.  You can jumper this switch (on the accumulator) to test the electrical portion of the circuit and verify the compressor will come on.  Don't run the compressor long, though, if the pressures are low.
The schematic of the system is different if you EATC or manual A/C controls... and it gets a little complicated.
Hope this helps...
Clay