Refrigerant Pressure Sensor / Switch: Description and Operation

AIR CONDITIONING PRESSURE TRANSDUCER - PCM INPUT
The Powertrain Control Module (PCM) monitors the A/C compressor discharge (high side) pressure through the air conditioning pressure transducer. The transducer supplies an input to the PCM. The PCM engages the A/C compressor clutch if pressure is sufficient for A/C system operation.