Refrigerant Pressure Sensor / Switch: Description and Operation
A/C PRESSURE SWITCHESThe A/C system is protected by two pressure switches. The A/C high pressure switch interrupts the A/C request signal when the A/C line pressure exceeds a predetermined value. The A/C low pressure switch interrupts the A/C refrigerant low pressure switch signal when the A/C line pressure falls below a predetermined value. When the PCM sees an open in either signal, the A/C compressor clutch relay control circuit is no longer grounded, thus shutting off the compressor.