Caprice Wagon V8-350 5.7L (1994)
Refrigerant Pressure Sensor / Switch: Description and Operation
A/C Circuit.
Purpose:
The PCM utilizes this signal to enable cooling fans when head pressure reaches about 189 psi. If a fault is present in the A/C refrigerant pressure
sensor circuit, a DTC 66 and 67 will set, the A/C clutch would be disabled.
Operation:
A 5 volt reference is supplied to the sensor and returned to the PCM on the signal line. As A/C pressure increases or decreases, the resistance of
the sensor changes and varies the amount of signal returning to the PCM.
Location:
The A/C pressure sensor is located above the right hand front wheelhouse, in the high pressure line.