Patent ID: 7646287

Claim:
An antitheft apparatus for a vehicle comprising: an inertia sensor provided for an anti-lock braking system; an electronic control unit having a first control portion for determining whether there is a possible vehicle theft or not based on an output signal from the inertia sensor, and for outputting a vehicle theft signal when the first control portion determines the possible vehicle theft; a second control portion of the electronic control unit for receiving the vehicle theft signal from the first control unit portion, and for outputting a driving signal; and a warning device for raising an alarm indicating the possible vehicle theft, when the warning device receives the driving signal from the second control portion wherein the inertia sensor comprises an acceleration sensor for detecting acceleration in a direction on a plane parallel to a vehicle floor, wherein the first control portion calculates an inclined angle of a vehicle, based on the output signal from the acceleration sensor, and outputs the vehicle theft signal when the inclined angle is higher than a predetermined value, wherein the acceleration sensor comprises at least two detecting elements, each of which has its own detection direction in which acceleration is detected, and wherein one of the detection directions intersects with a vehicle longitudinal direction by a first angle, and the other detection direction intersects with the vehicle longitudinal direction by a second angle at an opposite side of the detection direction with respect to the vehicle longitudinal direction.