A method for detecting a function actuation on a motor vehicle with a sensor device includes monitoring the signals of a proximity sensor as to a first signal reply S1. The signals of the proximity sensor are monitored for a time period Ts wherein the method is interrupted when the signal reply changes by more than a value St within the period of time Ts. The signal device is actuated after time Ts has expired in order to signal to the user that the actuation of time has expired. The signals of the proximity sensor are monitored for time Te wherein the method is continued when the signal of the proximity sensor changes by more than a predetermined value Se within the period of time Te. Otherwise, the method is interrupted. If the method is continued, the actuation of the function of the motor vehicle is detected and the function trigger is signaled to a control device in the motor vehicle.