A/C Pressure Transducer
WARNING: This page is about a different car, the 2010 Lincoln MKX and 2010 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.
The A/C pressure transducer monitors the compressor discharge pressure and communicates with the PCM. The PCM will interrupt A/C compressor operation in the event that the A/C pressure transducer indicates high system discharge pressures. It is also used to sense low charge conditions. If the pressure is below a predetermined value for a given ambient temperature, the PCM will not allow the clutch to engage. It is not necessary to recover the refrigerant before removing the A/C pressure transducer.