PURPOSE: To make a help function for outputting operation guidance certainly work by giving a shock to a device by an operator when operation is not understandable at the time of executing prescribed processing in accordance with the input of the operation.

CONSTITUTION: A shock detection processing part 5 judges the level of the output signal of a shock sensor 4, and if the level is below a threshold set beforehand, it then judges the shock to be a noise, and its does not respond at all. If the level of the output signal exceeds the threshold, then the shock is judged to be the request of the operation guidance, and the output command of the operation guidance is given to an ECU 1. In response to it, the ECU 1 displays the prescribed operation guidance on the screen of a display part 3 in conformity with the program of the help function set beforehand. At that time, the ECU 1 displays the whole of the operation guidance when the output command of the operation guidance is imparted from the beginning of operation procedure for executing the prescribed processing is given, and its displays the operation procedure after the point of time of the issuance of the request of the operation guidance when the request of the operation guidance on the way of the operation procedure is issued.