AUTONOMOUS DRIVING DEVICE, AUTONOMOUS DRIVING METHOD, AND PLURALITY OF NON-TRANSITORY STORAGE MEDIA

An autonomous driving device to be mounted on a vehicle includes a first ECU configured to autonomously drive the vehicle, and a second ECU configured to operate the vehicle under remote control from an outside. The first ECU is configured to keep an activated state while the second ECU is operating the vehicle. The second ECU is configured to keep a power saving state while the first ECU is autonomously driving the vehicle.