2005 Toyota Sienna A/C

A/C not working I have check for power at the presure switch there is none also no powere at the compresser, I have checked all the fuses that I know about and have switched the relay but nothing also ran 12v power to the compresser also nothing, tried adding a can of of freon to see if it would kick the presure switch on but also this did not work.
I would like to make sure that the compresser is the problem before I replace it. Im concrened that there is no power there.
Any suggestion?