BATTERY-DEGRADATION REPORTING DEVICE

PROBLEM TO BE SOLVED: To more surely inform a decrease in battery voltage of a portable machine to a user. SOLUTION: A battery-degradation reporting device informs the decrease in the battery voltage of the portable machine to the user. A smart key system 1, which configures a process where the user before getting on a vehicle till getting off the vehicle as one sequence, executes at least four portable-machine authentication processings containing: a portable-machine-authentication processing in communicating with the portable machine 40 outside the vehicle in a parking state; a portable-machine authentication processing in communicating with the portable machine inside the vehicle after a door lock is released; a portable-machine authentication processing in communicating with the portable-machine inside the vehicle when an engine or a vehicle power source is turned off; and a portable-machine authentication processing in communicating with the portable machine outside the vehicle when locking the door is instructed. When the battery degradation reporting device detects the battery-decrease in the portable machine based on a battery state signal received during each of the four portable machine authentication processing, information on the decrease in the batery for representing the battery degradation in the portable machine is visually outputted. COPYRIGHT: (C)2011,JPO&INPIT