To give an emergency running characteristic to a failed tire by co-operating a charging device with an electric switch, and triggering visual and/or acoustic signals by the switch after the charging device is taken out from a storage room.

After abnormal pressure loss of a tire is detected, a charging device 8 is removed from receiving parts 15, 16 through holding devices 13, 14 and taken out of a storage room 7. By this take-out of the charging device 8, an electric switch 11 is changed over so that visual and/or acoustic signals are triggered. The failed tire is charged with a seal medium and a pressure medium by the charging device 8, whereby the tire is put in the condition of having an emergency running characteristic. The tire having the emergency running characteristic is replaced by a tire having perfect function. Subsequently, the charging device 8 is again inserted in the storage room 7 by the holding devices 13, 14 and the receiving parts 15, 16. Subsequently, the electric switch 11 cuts off a signal to a power consumption device.