First, put everything back to normal, pressure switches rarely go bad.
You need to unplug and measure the connector on the A/C compressor clutch. It should be a dark blue/black wire. The engine must be running with max A/C selected. If you are reading 0V, pull the low side pressure switch and jump the brown wire to ground. If the compressor does engage, plug the sensor back in and jump the dark blue wire from the high side switch to ground. If the compressor doesn't work, check the low side switch and wiring for continuity. If it does work, check the high side switch for continuity, if it checks good, check the light green/white wire for continuity to ground. If it doesn't check out, the wire is damaged between there and the A/C select switch.
If everything has checked out so far move to the underhood PDC.
Look for the A/C compressor clutch relay. pull it and probe pin 30 on the PDC, you should read battery voltage. If you didn't, replace fuse J in the PDC. If you did read battery voltage, probe pin 86, if there is no voltage, replace fuse 11 in the cabin junction block. If there is battery voltage on pin 86, switch to resistance and probe from ground to pin 85, you should read near 0 ohms. If you read near 0 ohms, swap the relay for a known good relay. If the known good relay clicks, probe for resistance from pin 87 to the dark blue/black wire on the compressor clutch, you should read near 0 ohms. If not, the wire is damaged and needs to be replaced.
If everything has checked out so far, use a fused jumper wire to jump the A/C compressor clutch to battery positive, if it fails to engage, replace the clutch.