Refrigerant Pressure Sensor / Switch: Description and Operation
AIR TEMPERATUREA/C Refrigerant Pressure Sensor
The A/C refrigerant pressure sensor is a 3 wire piezoelectric pressure transducer. A 5 volt reference, low reference, and signal circuits enable the sensor to operate. The A/C pressure signal can be between 0-5 volts. When the A/C refrigerant pressure is low, the signal value is near 0 volts. When the A/C refrigerant pressure is high, the signal value is near 5 volts.
The A/C refrigerant pressure sensor protects the A/C system from operating when an excessively high or low pressure condition exists. The powertrain control module (PCM) disables the compressor clutch under the following conditions:
- A/C pressure is more than 2968 kPa (430 psi).
- A/C pressure is less than 255 kPa (35 psi).