determining, by a processor, whether an internal combustion engine is overheated based on driving information of the vehicle and cooling information of a passenger compartment while the vehicle is driving and a heating, ventilation, and air conditioning (HVAC) system is operating in a cooling mode by determining whether a temperature of an engine coolant discharged from the internal combustion engine is higher than a first threshold temperature;

controlling, by the processor, an alternator or an actuator of a switching door to reduce a cooling capacity provided by the HVAC system when it is determined that the internal combustion engine is overheated;

determining whether an accumulated cooling capacity provided by the HVAC system exceeds a reference accumulated cooling capacity after the cooling capacity is reduced;

determining a lower limit temperature of an evaporator of the HVAC system according to a temperature of an engine coolant when the accumulated cooling capacity exceeds the reference accumulated cooling capacity; and

repeatedly turning a clutch of a compressor of the HVAC system on or off by comparing a temperature of the evaporator and a lower limit temperature of the evaporator,

wherein the clutch is turned off when the temperature of the evaporator is lower than the lower limit temperature of the evaporator,

wherein the clutch is turned on when the temperature of the evaporator is higher than a restart temperature, and

wherein the restart temperature is the sum of the lower limit temperature of the evaporator and a restart hysteresis temperature.