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 DEF filler neck is under the cargo
compartment floor.
X Switch the ignition off.
X Open the tailgate.
X Lift up the cargo compartment floor
(Y page 312). X
Turn DEF cap 0002counter-clockwise and
remove it. X
Turn DEF filler cap 0003counter-clockwise
and open it.
Filler cap 0003is secured with a plastic strip. X
Unscrew the protective cap from DEF refill
bottle 0021.
X Set DEF refill bottle 0021as show nonthe
filler neck and screw it on hand-tight.
X Press DEF refill bottle 0021downward.
The DEF tank is filled. This may take up to
one minute.
i To top up between service intervals, fill
the DEF tank with approximately 1 gal
(3.8 l) of DEF.1g al (3.8l) DEFi s equivalent
to approximately 2DEF refill bottles. Then
have the DEF supply checked at a qualified
specialis tworkshop and completely refilled
if necessary.
X Release DEFr efill bottle0021.
When DEFr efill bottle0021is no longer
pressed down, filling stops. DEFr efill bottle
0021 can be removed when it has been only
partially emptied.
X Turn DEFr efill bottle 0021counter-clockwise
and remove it.
X Place DEFf iller cap0003on the filler nec kand
turn it clockwise. Refueling
159Driving and parking Z
Checking the tire pressures
Important safety notes Observe the "tire pressure information"
sectio n(Ypage 331).
Information on air pressure for the tires on
your vehicle can be found:
R on the vehicle's Tire and Loading
Information placard on the B-pillar
R on the tire pressure label on the fuel filler
flap
R in the "Tire pressure information" section
Checking tire pressures manually To determine and set the correct tire
pressure, proceed as follows:
X Remove the valve cap of the tire that is to
be checked.
X Press the tire pressure gauge securely onto
the valve.
X Read the tire pressure and compare it with
the recommended value on the Tire and
Loading Information placard on the
B-pillar on the driver's side of your vehicle.
X If necessary, increase the tire pressure to
the recommended value (Y page 331).
X If the tire pressure is too high, release air
by pressing down the metal pin in the valve
using the tip of a pen, for example. Then,
chec kthe tire pressure again using the tire
pressure gauge.
X Screw the valve cap onto the valve.
X Repeatt hese steps for the other tires. Tire pressure loss warning system
(Canada only)
General notes While the vehicle is in motion, the tire
pressure loss warning system monitors the
set tire pressure using the rotational speed of
the wheels. This enables the system to detect
significant pressure loss in a tire. If the speed of rotation of a wheel changes as a result of
a loss of pressure, a corresponding warning
message will appearint
he multifunction
display.
You can recognize the tire pressure loss
warning by the Run Flat Indicator Active Press 'OK' to Restart message
which appears in the Service menu of the
multifunction display. Further information on
the message display can be found under
"Restarting the tire pressure loss warning
system" section (Y page 336).
Important safety notes The tire pressure warning system does not
warn you of an incorrectly set tire pressure.
Observe the notes on the recommended tire
pressure (Y
page 331).
The tire pressure loss warning system does
not replace the need to regularly check your
vehicle's tire pressures, since an even loss of
pressure on several tires at the same time
cannot be detected by the tire pressure loss
warning system.
The tire pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tire is penetrated by a foreign object. In the
event of a sudden loss of pressure, bring the
vehicle to a halt by braking carefully. Avoid
abrupt steering maneuvers.
The function of the tire pressure loss warning
system is limited or delayed if:
R snow chains are mounted on your vehicle's
tires.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style
(cornering at high speeds or driving with
high rates of acceleration).
R you are towing a very heavy or large trailer.
R you are driving with a heavy load (in the
vehicle or on the roof). Tire pressure
335Wheels and tires Z