A/C Refrigerant Pressure Sensor
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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 pressure condition exists. The HVAC control module disables the compressor if the A/C pressure is more than 3295 kPa (478 psi) or less than 14.9 kPa (2.17 psi).