| 摘要 |
An immobilizer ECU (20) compares reference code stored therein and a password code sent from a key (10). When the engine speed reaches 500 rpm, an engine ECU (24) transmits a rolling code A. If the above codes coincide with each other, the immobilizer ECU (20) transmits a rolling code B. If the engine ECU (24) does not receive the rolling code B within a predetermined time, the engine ECU (24) stops the engine. A counter CIMMOF which increments at the initial stage of this processing is provided, and the counter CIMMOF is reset only when it comes to a normal end. If the ignition is turned off before the communication of the rolling codes comes to an end, the counter CIMMOF is made to count up. Then, the time required to wait for the rolling code B is sequentially shortened according to the value of the counter CIMMOF. When the above processing comes to an end and when the backup power source for a backup memory (24d) is disconnected, the communication timing of the rolling codes is made earlier. This prevents the engine from being able to be started due to cutting of a communication line or the like. <IMAGE> |
