[Problem] To be able to detect overwinding and transmit and receive information on a single line, and prevent emission of radio waves in advance. [Solution] A crane vehicle comprises a traveling body 20, a turning body 40, a boom 50, and a signal line SL. The traveling body 20 and the turning body 40 have a battery 24 and a first control circuit 60. The boom 50 has an overwinding switch SW and a second control circuit 70. The first control circuit 60 has an electromagnetic relay 62, a stop circuit 64, and a first modulation-demodulation circuit 66 and the second control circuit 70 has a second modulation-demodulation circuit 76, and a second power source circuit 71. When the overwinding switch SW is in an opened state, the electromagnetic relay 62 is in a closed state. When the electromagnetic relay 62 is in a closed state, the stop circuit 64 stops driving of the first modulation-demodulation circuit 66. In addition, when the overwinding switch SW is in the opened state, the supply of DC voltage to the second modulation-demodulation circuit 76 from the second power source circuit 71 is stopped. As a result, the emission of radio waves is prevented in advance.