Abstract: In a control unit for the manually operable control of the lifting and lowering and/or upward tilting in a vertical position and the back-tilting of a loading platform of a loading platform system, which can be mounted on vehicles, particularly trucks, and which includes an electromechanical and/or electronic control circuit, a first light for characterizing an operating condition of the loading platform system is provided, wherein the control circuit is so designed, that, if after initiation of the operation of the loading platform system, the first light lights up, the supply voltage of the loading platform system is indicated to be at least sufficiently high for proper operation of the loading platform system.