Volvo XC 90 EXCELLENCE 2018 Owner's Manual Supplement page 12

USB PORT AND ELECTRICAL SOCKET
LOCATIONS
USB ports: There are two USB ports under the armrest in the rear
seat. The screen brackets on the rear of the front seat head restraints
also include two USB ports. The ports can be used to e.g. charge a
mobile phone or tablet.
It is not possible to playback media in the car's audio system via the
USB ports.
Electrical sockets: There is one 12 V socket and one 230 V socket
under the armrest in the rear seat.
230 V: The socket can be used for various accessories requiring a
230 V supply, such as chargers or laptop computers.
– Plug in the accessory's connector. Disconnect the accessory by
unplugging the connector.
12 V: The socket can be used for various accessories requiring a 12 V
supply, such as music players or mobile phones.
– Remove the cigarette lighter from the socket and plug in the
accessory's connector. Unplug the accessory's connector and refit
the cigarette lighter when the socket is not in use.
The car's electrical system must be in at least ignition position I for the
USB ports and electrical sockets to supply power.