Patent ID: 7486170

Claim:
A vehicle antitheft device, comprising a portable unit and an onboard unit for performing an authentication processing through radio communication between the portable unit and the onboard unit and issuing a starting control command to a side of a vehicle drive control unit upon fulfillment of authentication, wherein with a view to starting the vehicle without using the portable unit, the onboard unit comprises: wiring conductiveness detecting section for detecting that terminals of a predetermined electric wiring outside the onboard unit have been connected and made conductive by a connecting element; mechanical key position detecting section for detecting a predetermined signal from a mechanical key mechanism outside the onboard unit, the mechanical key mechanism generating the predetermined signal when a mechanical key has been inserted into a key cylinder and assumes a predetermined position; password detecting section for detecting a signal generated through operation of a password manual entry switch outside the onboard unit; and starting control command generating section for generating a starting control command to the side of the vehicle drive control unit when a predetermined password is entered after conductiveness of the predetermined electric wiring and occupation of the predetermined position by the mechanical key have been detected as a result of detection carried out by said wiring conductiveness detecting section, said mechanical key position detecting section, and said password detecting section.