Closing
•► Replace the fuel filler cap and turn it clockwise. The fuel filler cap audibly engages.
•► Press the fuel filler flap closed until it engages audibly.
If you drive with the fuel filler cap open,
reserve fuel warning lamp 
flashes.
In
addition, the 
Check Engine warning
lamp may light up. A message appears in
the multifunction display.
For further information on warning and indicator lamps in the instrument cluster
Close the fuel filler flap before locking the vehicle. A locking pin otherwise prevents the fuel filler flap from closing after the vehicle has been locked.
See also:
Center console
Center console
...
Socket in the front-compartment center console
To open: slide cover 1 forwards until it engages.
Lift up the cover of socket 2.
To close: press cover 1 briefly at the front. The cover moves back.
...
The Inside
The C-Class wears the three-pointed star, but closer scrutiny reveals areas
of cost-cutting versus the $35,000 competition, let alone Mercedes' pricier
cars. It's the sort of thing that requires a ...