A/C Refrigerant Pressure Sensor
WARNING: This page is about a different car, the 2002 Pontiac Sunfire and 2002 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
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 zero 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 432 psi (2979 kPa).
- The clutch will be enabled after the pressure decreases to less than 219 psi (1510 kPa).
- A/C pressure is less than 27 psi (186 kPa).
- The clutch will be enabled after the pressure increases to more than 30 psi (207 kPa).