Antitheft device for automobile

TL;DR: In this article, a relay switch having a normally opened contact is arranged in series with a wiring for connecting an engine key switch 10 and a sel-motor 11 to each other, and a controller is provided for receiving a specified signal transmitted from a portable transmitter 1 and controlling the relay switch for a specified period when a specified condition is satisfied.

Abstract: PROBLEM TO BE SOLVED: To provide an automobile antitheft device capable of surely preventing a theft. SOLUTION: A relay switch 12 having a normally opened contact is arranged in series with a wiring for connecting an engine key switch 10 and a sel-motor 11 to each other. A controller 13 is provided for receiving a specified signal transmitted from a portable transmitter 1 and controlling the relay switch for a specified period when a specified condition is satisfied. Since the relay switch is normally opened, if the portable transmitter is not carried, the starter motor is not rotated and an engine is not started even if the engine switch is broken and the wiring is directly connected. Therefore, a theft can be reliably prevented. A regular driver closes the contact of the relay switch by operating the controller by carrying the portable transmitter, operates the engine key 3 to rotate the starter motor, and starts the engine.