Mercedes-Benz S-Class 2013 Owners Manual - Manual (Page 328)

residues crystallize after time and
contaminate the affected surfaces.
! DEF is not a fuel additive and must not be
added to the fuel tank. If DEF is added to
the fuel tank, this can lead to engine
damage.
! Only screw on the DEF refill bottle hand-
tight. It could otherwise be damaged.
The filler neck for DEF is located under the
"Minispare" emergency spare wheel in the
trunk floor.
X Switch off the ignition.
X Open the trunk.
X Lift the trunk floor up (
Y
page 442).
X
Turn the "Minispare" emergency spare
wheel fastening in the direction of the
arrow and remove it.
X Remove the "Minispare" emergency spare
wheel.
X
Turn DEF cap : counter-clockwise and
remove it.
X Turn DEF filler cap ; counter-clockwise
and open it.
Filler cap ; is secured with a plastic strap.
X Unscrew the covering cap from DEF refill
bottle =.
X Place DEF refill bottle = on the filler neck
as shown and screw on clockwise hand-
tight.
X Press DEF refill bottle = down.
The DEF tank is filled. This may take up to
one minute.
i To add between service intervals, fill the
DEF tank with approximately 1 gal (3.8 l) of
DEF. 1 gal (3.8 l) of DEF is equivalent to
approximately 2 DEF refill bottles. Then
have the DEF supply checked at a qualified
specialist workshop and completely refilled
if necessary.
X Release DEF refill bottle =.
Refilling stops when the DEF refill bottle is
no longer pressed down. The DEF refill
bottle can be removed when it has been
only partially emptied.
326
Refueling
Driving
and
parking