Refrigerant Pressure Sensor / Switch: Description and Operation
Air Conditioning (A/C) Refrigerant Pressure SwitchThe Air Conditioning (A/C) refrigerant pressure switch is located along the right front inner fender. The A/C refrigerant pressure switch is in the liquid pipe between the receiver/dryer and the evaporator. The A/C refrigerant pressure switch acts in order to cycle the compressor on and off under conditions of abnormally low or abnormally high refrigerant pressure.
If the pressure drops below 193 kPa (28 psi) or rises above 3137 kPa (455 psi), the A/C refrigerant pressure switch opens. The A/C refrigerant pressure switch signals the A/C compressor control module to shut down the compressor.
An insufficient refrigerant supply or a very low refrigerant temperature can cause an abnormally low refrigerant pressure. Extremely high refrigerant temperatures or an overcharging of the system during servicing can cause an abnormally high refrigerant pressure.