If any electrical devices are not working, turn the ignition switch to LOCK 0*1 and check to see if any applicable fuse is blown.
Honda Civic Owners Manual. When You Cannot Unlock the Fuel Fill
Door
What to Do When Unable to Unlock the Fuel Fill Door
If you cannot unlock the fuel fill door, use the following procedure.
Open the trunk.
Pull the green release cord beneath the rear
tray to the right.
► The release cord unlocks the fuel fill door
when it is pulled ...