Refrigeration System

A/C Pressure Sensor

An electronic A/C pressure sensor is mounted on the discharge line (high side) of the A/C compressor suction/discharge hose assembly. Its output to the PCM is variable and is dependent upon pressure inside the line. The PCM communicates the status of the A/C system pressure to the Body Control Module (SDM) via class 2 serial data. A higher pressure results in a higher voltage output. A/C pressure is constantly monitored to:

^ Disengage the A/C clutch if the pressures are high-2968 kPa (430 psi).
^ Disengage the A/C clutch if pressures are too low-below 255 kPa (37 psi).