ON-BOARD CHARGING AND COMMUNICATION DEVICE AND VEHICLE CHARGING AND COMMUNICATION SYSTEM

In order to prevent a PLC modem belonging to an onboard electronic control unit from being activated in vain, an onboard charging communication device and a vehicular charging communication system according to the invention are equipped with an onboard battery that is charged by being supplied with power from an external charger via a charging cable, and the onboard electronic control unit, which has a power line communication function for establishing power line communication with the aforementioned external charger via the aforementioned charging cable through the use of the PLC modem. The aforementioned onboard electronic control unit further has PLC modem activation control means for activating the PLC modem if the aforementioned power line communication function is validated and stopping the PLC modem from being activated if the aforementioned power line communication function is not validated on the other hand.