To provide an electronic key device which allows a user in possession of a plurality of portable machines to determine which portable machine has lowered battery voltage.
Each of the portable machines 3 of an electronic key device 100 comprises lowered battery voltage determination means 35 which measures the voltage of a self-contained battery 38 so as to detect voltage reduction, and warning means 36 which gives warning when the reduced voltage of the battery is detected by the lowered battery voltage determination means 35. During transmission of a response signal 40 in response to a request signal 4 from an in-vehicle machine 1, the lowered battery voltage determination means 35 performs voltage measurement. When the reduction in battery voltage is detected, a certified response signal 50 composed of response data with the addition of the information of the reduction in battery voltage is transmitted to the in-vehicle machine 1, and the warning means 36 gives warning. Consequently, a user in possession of the plurality of portable machines 3 can easily determine which portable machine 3 has lowered battery voltage.
| JP2003056230A | 2003-02-26 | |||
| JP2010062736A | 2010-03-18 | |||
| JP2010232873A | 2010-10-14 | |||
| JP2003003709A | 2003-01-08 |
Toshihide Kodama
Takenaka Ikuo
Keigo Murakami
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