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:
Resetting triggered NECK-PRO head
restraints
WARNING
For safety reasons, have the NECK-PRO head
restraints checked at an authorized
Mercedes-Benz Center after a rear-end
collision.
WARNING
When pushing back the NECK-PRO head
r ...
Purity
Assuring the purity of DEF is particularly
important with respect to avoiding
malfunctions in the exhaust gas
aftertreatment system.
If DEF is pumped out of the DEF tank, e.g. during repair wor ...
General notes
USA only:
This device complies with Part 15 of the FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful interference, and
2. this device must a ...
