Compressor Clutch

The compressor pulley is driven by a belt from the crankshaft; a compressor clutch is used to engage/disengage the pulley and driveshaft. The clutch is electromagnetic. When power is provided to the clutch, the clutch engages and rotates the compressor drive shaft. When the power is cut off, the clutch disengages and the compressor pulley free-wheels. The compressor is cycled on and off, according to evaporator temperature; it is also cycled off at full-throttle, standing start acceleration conditions.