Does the ac system have to be empty to change high pressure switch on 2006 jeep liberty. I have tested everything on the system electrical and I have power ac is full of Freon but clutch will not engage. Jumpered low pressure switch and still no ac
Before tearing into the AC system I would cross all my t's and dot my I's.
The fastest way to check a big chunk of the system is by using the clutch relay. Most relays (not all) can be opened and plugged back in. By pushing on the contacts with your finger the fuse and wiring is checked if the clutch comes on and off. If it does not come on then check the fuse and wiring. If the relay can't be disassembled then unplug the relay and jumper across the load side of relay.
If all that checks out ok then explore the control system. If you think that it might be a high side switch issue then jumper the switch (carefully) to verify first before replacing things.