A method in which a base station installed in each of a plurality of sections of a route, an antenna which is connected to the base station and installed along the route, and a control device which controls all the base stations installed along the route are used includes: measuring a strength of a signal emitted from the antenna in at least one mobile body in operation; acquiring a temporary failure determination result based on the signal strength, transmitting announcement information by the control device via the base station and the antenna to which it is determined that a failure occurs when the temporary failure determination result is acquired, transmitting an answer to the control device by an arbitrary mobile body in operation and receives the announcement information, and making a final failure determination based on the answer transmitted from each mobile body in the control device.