Be absolutely sure the clutch is engaged!

If it engages and the pressures move some when it does engage, then the compressor is a likely candidate. The compressor is a variable displacement type. That means it doesn't ever shut off to control evap temp. The way it controls is that internally a device like a POA valve maintains evap pressure by reducing pumping capacity. It does that by decreasing the angle of the wobble plate.

BTW POA stands for pilot operated absolute which used to sit in front of the rest of the device called a STV. So the whole device is thus called a pilot operated absolute suction trottling valve. It maintained evap temp by throttling the suction at the exit from the evap. Now similar control is inside the compressor.

Pressures as you state are usually due to lack of pumping capability.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician