Opening the DEF filler cap
The filler neck for DEF is behind the fuel filler flap.
The fuel filler flap is unlocked or locked automatically when you open or close the vehicle with the SmartKey or with KEYLESSGO.

- Switch off the ignition.
- Press the fuel filler flap in the direction of
arrow 1.
The fuel filler flap swings up.
- Turn blue DEF filler cap 2
counterclockwise and remove it.
DEF filler cap 2 is secured with a plastic
strap.
See also:
NECK-PRO head restraints
Resetting the NECK-PRO head
restraints
requires a lot of strength. If you have
difficulty resetting the NECK-PRO head
restraints, have this work carried out at a
qualified specialist worksh ...
2008 Mercedes-Benz M-Class Review
Until a 2008 M-Class was assigned to me for this review, I had kind of
forgotten that Mercedes redesigned this luxury SUV two years ago. Sure, I knew
about the update when it was first announced, ...
Exhaust check
WARNING
Inhalation of exhaust gas is hazardous to your
health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and possible death.
Do not run the eng ...
