Vehicle Automatic Defrost System and Control Method for External Window Surface

A system for automatically controlling a defog/defrost function of a vehicle climate control system includes a controller configured to calculate an ambient dew point temperature value from a plurality of inputs received from a sensor array. The controller is further configured to set a condensation indicator if a calculated difference between a window exterior surface temperature value input received from the sensor array and the calculated ambient dew point temperature value is less than or equal to a predetermined threshold value. The controller actuates the vehicle climate control system defog/defrost function and/or a window wiper system in response to the set condensation indicator.