To eliminate the generation of a warning sound equal to a noise, reduce the maintenance cost and also expand the information range of an abnormal state extremely.

When the vibration sensor 2 and door release sensor 3 installed in a vehicle 1 perceive the abnormality of the vehicle 1, an abnormal state detection signal is transmitted to an abnormal signal generation circuit 4. Samely, the slave instrument 5 of a small electric power type cordless telephone installed in the vehicle informs the abnormal state to the master instrument 7 of the small electric power type cordless telephone in response to the order from the abnormal signal generation circuit 4. When this information is not received by the master instrument 7 of the small electric power type cordless telephone due to the absence of the user, information is given to a portable telephone 9 as the forwarding address of the abnormality information.