A/C Pressure Sensor

A/C Pressure Sensor:

PURPOSE
The 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.

OPERATION
The PCM uses this input to determine A/C compressor load on the engine to help control idle speed with Idle Air Control (IAC) valve.

The A/C refrigerant pressure sensor electrical circuit consists of a S volt reference line, a ground line, 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. A problem in the A/C refrigerant pressure circuits or sensor should set a Diagnostic Trouble Code (DTC) P1530 will make the A/C compressor clutch inoperative. A faulty ground circuit at the sensor will result in a fixed high pressure value.

Refer to DTC P1530 for diagnosis of the A/C refrigerant pressure sensor. P1530