Patent ID: 6683391
Filing Date: 2004-01-27
Classification: B60R

Abstract:
A method of preventing vehicle thefts and recognizing and authorizing a new key in a system having a key cylinder and a controller mounted on a vehicle and a key insertable in said key cylinder for switching on a main switch for activating a prime mover of the vehicle, the key having a built-in transponder containing an ID code of the key to be sensed when the key is inserted in the key cylinder by the controller, said method comprising the steps permitting operation of the prime mover only when the ID code detected by the transponder coincides with an ID code which has been registered in the controller, inserting only a single recognized and authorized key capable of activation the prime mover in the key cylinder, switching the key cylinder to an on condition, removing the single recognized key capable of activating the prime mover, and maintaining a source of power for the prime mover for a predetermined time period after the single recognized and authorized key capable of activating the prime mover is removed and recognizing and authorizing the next key having a built-in transponder containing an ID code next inserted into the key cylinder within the predetermined time period.