To eliminate a mechanical holding mechanism to turn on a power source by using a memory card storing an ID code.

A card passing groove 3 is arranged in a card reader 2, and when a memory card 1 is passed through the card passing groove 3, an ECU 5 discriminates an ID code of the memory card 1, and when the ID code adapts to the memory card 1, a power source is turned on in a driving circuit of an engine. The power source of the driving circuit of the engine is turned off by a push-button switch 12 interlocking with a kill switch 8 and a handle lock lever 11 regardless of the memory card 1.