An adjustment device for adjusting a relative rotational angle position of two shafts (particularly a cam shaft and a crank shaft of an internal combustion engine) that has an adjusting gear which is designed as triple shaft gear and has a drive part connected to a first shaft (crank shaft), a driven part connected to a second shaft (cam shaft), and an adjustment shaft connected to a servomotor shaft of an electric servomotor in a rotationally fixed manner. In order to implement a wide temperature range for the operation of the adjustment device, a temperature sensor is arranged in the servomotor. In a method for operating an adjustment device or an actuator, the current of the servomotor or the actuator is controlled depending on the temperature that was determined earlier.