Mahle AC pressure switch ASW19000S

An AC pressure switch in a car is a crucial component of the air conditioning system. Its main function is to monitor the pressure of the refrigerant in the AC system and control its flow accordingly. The switch is typically located on the high-pressure side of the system, often near the compressor or the receiver-drier. A pressure switch consists of a sensor, which measures the pressure, and a switch mechanism that either opens or closes based on the pressure readings.

When the pressure in the AC system reaches a certain predetermined level, the pressure switch will activate. If the pressure is too high, indicating a potential risk of damage to the system, the switch will open and interrupt the power supply to the compressor. This prevents the compressor from further pressurizing the system and causing potential damage. On the other hand, if the pressure drops too low, indicating a lack of refrigerant, the switch will close and allow the compressor to kick on, ensuring proper cooling of the car's interior.