Refrigerant Pressure Switch. Type Transducer. ???? © ISUMO® Error Codes • P0530 – A/C Refrigerant Pressure Sensor Circuit • P0531 – A/C Pressure Sensor Range/Performance • P0532 – A/C Pressure Sensor Low Input • P0533 – A/C Pressure Sensor High Input • P0534 – A/C Refrigerant Loss Detected.