Patent ID: 6525433
Filing Date: 2003-02-25
Classification: B60R

Abstract:
A method of preventing vehicle thefts 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, conditioning the controller to memorize an ID code of a newly recognized key by inserting a key having a specific ID code into the key cylinder to turn the main switch on and withdrawing the key having the specific ID code without starting the prime mover, and thereafter registering an ID code of the newly recognized key if inserted into the key cylinder within a predetermined time period.