When connection of a charging gun is detected, a charging-control ECU wakes up, and turns on a power supply relay to activate a charging-communication ECU. The charging-control ECU subsequently actives a power-control computer by communicating therewith. The power-control computer closes an SMR, and closes a power supply switch to activate a monitoring unit. If an abnormality occurs in inband communication, the charging-control ECU opens the power supply relay, instructs the power-control computer to shift into sleep mode, and subsequently shifts itself into sleep mode. The power-control computer opens the SMR and the power supply switch, and subsequently shifts into sleep mode.