PURPOSE: To obtain an effective notifying action by a method in which a transmitter-receiver device for actuator control signals and each displayer for brightness, sound, and luminescence are provided, and in response to actuator control according to signals and detected results, the displayers are selectively operated.

CONSTITUTION: The control signals of actuator are sent to a transmitterreceiver circuit 3, antenna 4, and operator 5 by a transmitter 1 and put from a receiver circuit 7 into a control circuit 8. Also, detected results of illumination sensor 9, mode switch 10, door opening and closing means 11, and bonnet opening and closing means 12 are input to control a phon 13, a stop display lamp 14, and a door lock mechanism 15. Antitheft action is started by the control circuit 8, and on the basis of the results of the sensor 9 and condition of the switch 10, the phon 13 and the lamp 14 are operated two times. By receiving the control signals as unlock, the antitheft action is stopped. Effecgive notifying action can thus be made according to the environmental conditions.