Mercedes-Benz 2008 R 320 CDI 4MATIC Operator's Manual page 477

Practical hints
Unlocking/locking in an emergency
Insert a suitable object such as a coin
into the slot of lock 1.
Turn lock 1 counterclockwise by 90°
in direction of arrow.
Remove cover 2.
3 Fuel filler flap release
Pull red fuel filler flap release 3 in
direction of arrow.
The fuel filler flap is unlocked.
Open the fuel filler flap ( page 352).
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