| 摘要 |
<p> This transmitting and receiving system has an ECU (1) that starts up from standby mode in fixed conditions and transmits a message by LF signal to the exterior in an interval in which a vehicle engine is stopped. Operation for transitioning to standby mode is repeatedly carried out if there is no response from a key (12) to the transmission. When the key (12) receives the message, the key (12) verifies the message with message data stored in advance and, if both match, transmits a response message to the ECU (1) by RF signal. The ECU (1) shortens and transmits the message when the remaining battery power falls below a lower limit value, and when the key (12) receives the shortened message, the key (12) performs verification within the range of the received message length, and, if both match, sends a response message to the ECU.</p> |
