A method includes applying a specified starting voltage to a valve actuator in a first specified operating mode for closing the valve, the valve having a spring with a spring force against which an actuator force of the actuator acts. In the first operating mode, a first period of time is ascertained which represents that a maximum current value has been reached. Furthermore, a second period of time is ascertained which represents that a minimum current value has been reached. In a specified second operating mode, the specified starting voltage is applied to the actuator until the end of the first period of time is reached, and a control voltage is then applied to the actuator until the end of the second period of time is reached, wherein the average value of the control voltage is lower than the average value of the starting voltage.