Mazda Motor Corporation

Naldec Corporation

Hiroshi Tagawa

Atsushi Okamitsu

Hiroshi Fujimoto

Kazufumi Adachi

Manabu Hirozawa

An anti-vehicle-thief apparatus registers specific ID codes of a plurality of keys, and determines validity of a key, for example, in accordance with an operation of the key 1 including a transponder having one of the registered specific ID codes. The anti-vehicle-thief apparatus registers a code specific to the key and confirms an operation in which an ignition switch is turned on and off five times by using the key, where this operation is for changing the ID codes specific to the plurality of keys registered in EEPROMs. After the confirmation of the operation, ID codes specific to a plurality of new keys are successively registered, thereby preventing a third person from using the old keys, as well as making registration of the ID codes specific to the new keys easily.

Anti-vehicle-thief apparatus and code setting method of the apparatus

A vehicle antitheft system has an immobilizer unit which reads in an identification code generated by and transmitted from an ignition key of the type having a built-in signal transmitter and compares the identification code read therein with an identification code having been entered therein to transmit an encoded word when there is a presence of coincidence between these identification codes, and an engine controlling unit which reads in the encoded word transmitted from the immobilizer unit and compares the encoded word read therein and an encoded word having been entered therein to permit itself to perform control of operation of the engine when there is a presence of coincidence between these encoded words.

Method of and system for entering identification codes into vehicle

In a vehicle antitheft system having an immobilizer unit which reads in an identification code generated by and transmitted from an ignition key of the type having a built-in signal transmitter, an ID code of a first ignition key is tentatively stored in the immobilizer unit until different ID codes of first and second ignition keys are registered even in the event where ID code entry operation is interrupted before registration of the first and second keys' ID codes during an entry of the first ignition key ID code and is resumed with the second ignition key.

Growing community of inventors

Hiroshima, Japan

Hiroshi Tagawa