To provide an immobilizer device effectively preventing the theft of a vehicle by changing an ECU.
The immobilizer device 30 includes a vehicular ECU 40 and a magnet 60 installed in the vicinity of the vehicular ECU 40. The vehicular ECU 40 includes a magnetic detection unit 44 for detecting magnetic distribution formed by the magnet 60, a magnetic storage unit 46 for storing the detection result of the magnetic detection unit 44 when the vehicle is in a predetermined state, and a control unit 48 which compares the detection result of the magnetic detection unit 44 with the detection result stored in the magnetic storage unit 46, permits the start of a vehicle drive device 2 when the comparison result is in agreement, and prohibits or restricts the start of the vehicle drive device 2 when it is not in agreement.
TANAKA MASAHIRO
ANDO ATSUHISA
