A control system adjusts the active state of an air conditioner system for automotive vehicles on the basis of the thermal environment in accordance with an automatic operation setting program. When a user inputs a modification request for adjusting the thermal environment within a vehicular cabin by means of a button switch while the air conditioner system operates in accordance with the program, the control system modifies the active state of the air conditioner system on the basis of the user's modification requests and the present thermal environment. The active state modification values are stored in a memory to be used in the adjustment of the active state until new modification values are entered by the user.
