A device for disinfecting components of an air conditioning system in a motor vehicle is provided. The device includes an ozone generator arranged in close proximity to an evaporator in the air conditioning system. The device further includes an electronic control unit configured to activate the ozone generator to produce a comparatively large amount of ozone sufficient to disinfect the evaporator. The electronic control device activates the ozone generator when information provided to the control unit indicates that a condition is met, under which air flaps between the air conditioning system and a passenger compartment of the motor vehicle may remain closed or are expected to remain closed for a time sufficient for the disinfection.