Mazda 626 GXi - W Reg

AC does not work! Green light is on, but no increase in RPM, no relay click from anywhere. Checked the fuses, two offside eng compartment relays and appear OK. No voltage at compressor wire (blue/red) when switching AC on/off.

How does AC operate? Is there a pressure switch in the circuit that (low side?). Could it be that system needs pressure in it to 'activate' circuit???

Will have it checked by Mazda, but would like to know before hand.