A/C Signal: Description and Operation
DescriptionThe Air Conditioning (A/C) refrigerant pressure sensor provides a signal to the Powertrain Control Module (PCM) which indicates varying high side refrigerant pressure between approximately 0 psi and 450 psi.
The PCM uses this input in order to determine the A/C compressor load on the engine in order to help control idle speed with the Idle Air Control (IAC) valve.
Operation
The A/C refrigerant pressure sensor electrical circuit consists of a 5 volt reference line and a ground line, both provided by the PCM, and a signal line to the PCM. The signal is a voltage that varies from approximately 0.1 volt at 0 psi, to 4.9 volts at 450 psi or more.
Circuit Faults
A problem in the A/C refrigerant pressure circuits or sensor may set a DTC P0530 and will make the A/C compressor inoperative.