DTC P0530: A/C Refrigerant Pressure Sensor Circuit: Description

Air Conditioning (A/C) pressure sensor is a transducer that varies resistance according to changes in high side refrigerant pressure. PCM measures signal voltage from A/C refrigerant pressure sensor, which is a reduced value of PCM 5-volt reference. Maximum voltage ranges of the sensor are around 0.1 volt at zero psi and 4.9 volts at 443 psi. Sensor input is primarily used by PCM to determine when to turn on cooling fans. Sensor input also aids in determining acceptable low/high refrigerant pressure for A/C operation and Idle Air Control (IAC) position for A/C idle speed. DTC sets when A/C pressure sensor signal voltage at PCM is more than or less than calibrated value.