| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent early exhaustion of a power source by cutting off power of an on-vehicle device, when length of stop time of the vehicle is determined and if the stop time is long, in a vehicle provided with an idling stop function. <P>SOLUTION: When the vehicle is stopped and if a current position detected by a car navigation system 1 is at an intersection or before a railroad crossing, the power source of the car navigation system 1 is switched to a lead acid battery 9 to a lithium-ion battery 10 since the stop of the vehicle is only temporary such as waiting at stoplights or waiting for a railroad vehicle to pass. Therefore, overflow of the car navigation system 1 caused by temporary voltage drop of the lead acid battery 9 at restart of an engine 7 is prevented. If the stop is not temporary, the overflow of the car navigation system 1 is performed at a time after five minutes or more from the stop of the vehicle. Therefore, early exhaustion of the lithium-ion battery 10 is prevented. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
