The accessory power socket can be used when the ignition switch is in ACCESSORY or ON *1.
Open the cover to use it.
NOTICE
Do not insert an automotive type cigarette lighter element: The power socket can overheat.
The accessory power socket is designed to supply power for 12 volt DC accessories that are rated 180 watts (15 amps) or less.
To prevent battery drain, use the power socket only when the engine is running.
Honda Civic Service Manual. Passenger's Dashboard Trim Panel Removal and Installation (Without Navigation)
8411K3
1.
Driver's Dashboard Lower Cover
1.
Remove the driver's dashboard lower cover (A).
2.
Dashboard Subdisplay Visor
...