SMART KEY SYSTEM

PROBLEM TO BE SOLVED: To provide a smart key system which can carry out unlocking control in case of confinement of a portable unit in a trunk, without being affected by a detection area of an in-trunk transmitter. SOLUTION: The smart key system 1 is formed of the portable unit 17 in which an ID code as authentication information intrinsic to a vehicle is recorded, the in-trunk transmitter 14 for transmitting in-trunk radio waves inquiring whether or not the portable unit 17 is present in a trunk, based on the ID code, a trunk control section 2 for detecting/identifying whether the trunk is in a locked condition or an unlocked condition, and a smart control section 3 for executing electric processing if the portable unit 17 is confined in the trunk. The smart control section 3 carries out cabin-side processing for checking a history as to whether or not the portable unit 17 has been present in a cabin when the trunk is unlocked, based on a change of the trunk from the unlocked condition to the locked condition, and in-trunk searching processing, and then carries out the electric processing on condition that nonexistence of the portable unit 17 in the cabin is determined based on the cabin-side processing and that confinement of the portable unit 17 in the trunk is determined based on the in-trunk searching processing. COPYRIGHT: (C)2006,JPO&NCIPI