Abstract: A group of information carrying flaps are pivoted to the circumference of a drum so that, upon rotation of the drum, the flaps drop down, one by one; the flaps carry information conveying indicia, for example trouble indication during operation of a motor vehicle. The drum is rotated by a motor. To display a specific information item, that is, to permit a specific flap to drop, the flaps are formed with conductive portions which are coded at an edge, the edges being engaged by the holding springs. If the code, which preferably is a binary code, matches that of a binary number entered into one terminal of a comparator, to which the holding springs are connected, the motor is stopped, thus displaying the specific information carried on the flap having the code which matches that of the code entered into the comparator.