Compressor Speed Sensor: Description and Operation

The speed sensor measures the speed of the A/C compressor

The pushbutton control module receives the speed signal from the A/C compressor speed sensor. This speed sensor is compared with the engine speed. When the drive slip between the engine and A/C compressor is > 30 %, the pushbutton control module provides power to the electromagnetic clutch switching off the electromagnetic clutch and therefore the A/C compressor. This protects the belt drive when the A/C compressor is locked up or hard to turn (V-belt protection).