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Refrigerant Pressure Sensor / Switch: Description and Operation

A/C REFRIGERANT PRESSURE SENSOR
The electronic A/C refrigerant pressure sensor is mounted to the line between the condenser and the evaporator. The output to the PCM is variable. The output of the PCM depends on the pressure inside of the line. A higher pressure will result in a higher voltage output.
The PCM constantly monitors the A/C system pressure in order to achieve the following effects:
^ Disengage the A/C clutch if the pressure is above 2700 kPa (440 psi).
^ Disengage the A/C clutch if the pressure is below 255 kPa (38 psi).
^ Boost the idle air control in order to compensate for the A/C load at idle.
^ Control the cooling fan operation.

Replace the pressure sensor if the pressure sensor fails. The pressure sensor is not repairable. Refer to A/C Refrigerant Pressure Sensor Replacement