An air conditioning system for a vehicle. The air conditioning system has a compressor, an evaporator and an intake door. The compressor is driven by a vehicle engine and a motor separately operable from the vehicle engine. The evaporator is disposed in a predetermined air passage to cool the air. The intake door is disposed upstream of the air passage, the intake door is switched between a first position and a second position. The intake door is arranged to introduce ambient air from outside of the vehicle in the first position and interior air from inside the vehicle in the second position. The air conditioning system is characterized in having a predicting means (51) for predicting an non-operating state of the vehicle engine (E), and a switching means (43) for switching the intake door (42) to the second position based on a prediction of the predicting means (51). <IMAGE>
