PURPOSE: To miniaturize a device and to reduce manufacture cost by simplifying wiring processes and using a connector having a little pin connectors.

CONSTITUTION: This confirming device for personal identification code detects personal identification codes by operating a circuit to be operated corresponding to the personal identification code inputted from a personal identification code input means 3 and prevents a current from reversely flowing to the circuit to be operated corresponding to the personal identification code by connecting a control circuit 1 through one terminal of the circuit to be operated corresponding to the personal identification code and a reverse flow block circuit 8. On the other hand, a switching circuit 5 is connected through the control circuit 1 and a cable in the signal processor and alarming/display is performed by the switching operation of the switching circuit 5. This control circuit 1 is connected through the switching circuit 5 to the reverse flow block circuit 8 by the signal cable, the control circuit is connected through the reverse flow block circuit 8 and the common signal cable and the number of signal cables connected with the control circuit 1 is reduced.