Firebird V8-5.7L VIN G (2001)
Refrigerant Pressure Sensor / Switch: Description and Operation
A/C REFRIGERANT PRESSURE SENSOR
The A/C system is protected by the A/C refrigerant pressure sensor. The sensors output to the PCM is variable and is dependent upon pressure inside the
line. A higher pressure results in a higher voltage output. The A/C pressure is constantly monitored in order to allow the A/C compressor clutch to
disengage as needed. If line pressures climb above 2826 kPa (410 psi) or fall below 207 kPa (30 psi), the PCM will turn off the A/C compressor clutch.
When high side pressures drop back down between 1034 kPa (150 psi) to 1724 kPa (250 psi), the PCM will allow the A/C compressor to operate.
A 5 volt reference signal is sent out over the 5 volt reference circuit, from the PCM, to the A/C refrigerant pressure sensor. The PCM reads the A/C
pressure by monitoring the voltage on the A/C refrigerant pressure sensor signal circuit. Ground for the A/C refrigerant pressure sensor is provided by
the low reference circuit.
