Circuit Description
WARNING: This page is about a different car, the 2004 Toyota Camry. However, it is still accessible from the selected car via links, so may be relevant.
The pressure switch sends the appropriate signals to the A/C amplifier when the A/C refrigerant pressure drops too low or rises too high. When the A/C amplifier receives these signals, it outputs signals via the A/C amplifier to switch OFF the compressor relay and turns the magnetic clutch OFF.