Just found this in the VX shop manual to help with identifying if the PS switch is bad:

POWER–ASSISTED STEERING SYSTEM 2A–33
"Pressure Switch Check the switch operation as follows: With engine idling and A/C on, turn the steering wheel fully to the left; compressor should interrupt and engine idle speed will increase. Shut off A/C and again turn
steering fully to the left; engine idle will increase. If system fails to function properly, disconnect connector at the pressure switch and repeat system check while testing continuity across disconnected SW connector."


I don't know exactly where this switch is but looks like it's at the bottom of the steering pump - wish someone has a pic