Patent ID: 7550869

Claim:
An on-vehicle apparatus theft deterrence system comprising: an on-vehicle apparatus that is adapted to be detachably installed to a vehicle and is lockable to implement activation lock of the on-vehicle apparatus and thereby to limit theft of the on-vehicle apparatus; and a plurality of activation lock releasing apparatuses that are usable to release the activation lock of the on-vehicle apparatus and are adapted to be attached to a plurality of portable items, respectively, of a user, wherein: each activation lock releasing apparatus includes: a storage means for storing an ID code that is used to release the activation lock of the on-vehicle apparatus; a wirelessly communicating means for transmitting the ID code to the on-vehicle apparatus through wireless communication; and a control means for controlling the storage means and the wireless communicating means; and the on-vehicle apparatus includes: an information obtaining means for obtaining the ID code from each communicatable one of the plurality of activation lock releasing apparatuses through wireless communication; a storage means for storing at least one authentication ID code; and a checking means for checking validity of each obtained ID code by comparing the obtained ID code with a corresponding one of the at least one authentication ID code; and when the checking means determines that the obtained ID code, which is obtained from at least one of the plurality of activation lock releasing apparatuses, is valid, the activation lock of the on-vehicle apparatus is released.