1999 Chevy Truck Cannot get compressor to run

I can make the compressor run and ac function with a jumper wire but, not with vehicle controls. I have checked all 3 pressure switches they are all closed, relay ok, fuses ok, and replaced the fan and temp controls in the dash. what is left? System refrigerant pressures are ok. a jumper wire at any of the three switches does not work. I do not have power at any of the wires to the pressure switches or the compressor clutch.