vehicle has tires of a different size than the
size indicated on the Tire and Loading Infor-
mation placard or the tire pressure label, you should determine the proper tire pressure for
those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring system (TPMS) that illuminates a low tire pres-
sure telltale when one or more of your tires
are significantly underinflated. Accordingly,
when the low tire pressure telltale illuminates,
you should stop and check your tires as soon as possible, and inflate them to the proper
pressure. Driving on a significantly underin-
flated tire causes the tire to overheat and can
lead to tire failure. Underinflation also
reduces fuel efficiency and tire tread life, and may affect the vehicle's handling and stop-
ping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the driv-
er's responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate if the
system is not operating properly. The TPMS
malfunction indicator is combined with the
low tire pressure telltale. When the system
detects a malfunction, the warning lamp will
flash for approximately a minute and then
remain continuously illuminated. This
sequence will be repeated every time the vehi- cle is started as long as the malfunction
exists.
When the malfunction indicator is illuminated,
the system may not be able to detect or signal low tire pressure as intended. TPMS malfunc-
tions may occur for a variety of reasons,
including the installation of incompatible
replacement or alternate tires or wheels on
the vehicle that prevent the TPMS from func-
tioning properly. Always check the TPMS mal-
function telltale after replacing one or more
tires or wheels on your vehicle to ensure that
the replacement or alternate tires and wheels allow the TPMS to continue to function prop-
erly.
It is the driver's responsibility to set the tire
pressure to that recommended for cold tires
which is suitable for the operating situation
(Y page 336). Note that the correct tire pres-
sure for the current operating situation must
first be taught-in to the tire pressure monitor. If there is a substantial loss of pressure, the
warning threshold for the warning message isaligned to the reference values taught-in.
Restart the tire pressure monitor after adjust-
ing the pressure of the cold tires
(Y page 341). The current pressures are
saved as new reference values. As a result, a
warning message will appear if the tire pres-
sure drops significantly.
The tire pressure monitor does not warn you
of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure (Y page 336).
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 tire pressure monitor has a yellow warn-
ing lamp in the instrument cluster for indicat-
ing a pressure loss or malfunction. Whether
the warning lamp flashes or lights up indi-
cates whether a tire pressure is too low or the tire pressure monitor is malfunctioning:
R if the warning lamp is lit continuously, the
tire pressure on one or more tires is signif-
icantly too low. The tire pressure monitor is not malfunctioning.
R if the warning lamp flashes for around a
minute and then remains lit constantly, the
tire pressure monitor is malfunctioning.
i In addition to the warning lamp, a mes-
sage appears in the multifunction display.
Further information can be found on
(Y page 256). 340
Tire pressureWheels and tires
Inflating the collapsible spare wheel
!
Inflate the collapsible spare wheel using
the tire inflation compressor before lower-
ing the vehicle. The wheel rim could other-
wise be damaged. X
Pull connector 0085and the air hose out of
the housing.
X Remove the cap from the valve on the col-
lapsible spare wheel.
X Screw union nut 0043on the air hose onto the
valve.
X Make sure on/off switch 0083of the tire
inflation compressor is set to 0.
X Insert plug 0085into the socket of the ciga-
rette lighter (Y page 284) or into a 12 V
power socket (Y page 284) in your vehicle.
X Make sure that the SmartKey is in position
1 (Y page 149) in the ignition lock.
X Press on/off switch 0083on the tire inflation
compressor to I.
The tire inflation compressor is switched
on. The tire is inflated. The tire pressure is
shown on pressure gauge 0087.
! Do not operate the tire inflation compres-
sor for longer than eight minutes at a time
without a break. It may otherwise overheat.
The tire inflation compressor can be oper-
ated again once it has cooled down.
X Inflate the tire to the specified tire pres-
sure. The specified tire pressure is printed on the
yellow label of the emergency spare wheel.
X When the specified tire pressure has been
reached, press on/off switch 0083on the
electric air pump to 0.
The tire inflation compressor is switched
off.
X Turn the SmartKey to position 0in the igni-
tion lock.
X If the tire pressure is higher than the speci-
fied pressure, press pressure release but-
ton 0044until the correct tire pressure has
been reached.
X Unscrew union nut 0043on the air hose from
the valve.
X Screw the cap onto the valve of the col-
lapsible spare wheel again.
X Stow plug 0085and the air hose in the lower
section of the blower housing.
X Stow the tire inflation compressor in the
vehicle.
Stowing a used collapsible spare wheel Take the following steps to stow a used col-
lapsible spare wheel. Otherwise, the collaps-
ible spare wheel will not fit in the spare wheel
well. Mercedes-Benz recommends that you
have this work carried out at a qualified spe-
cialist workshop.
! Only place the collapsible spare wheel in
the vehicle when it is dry. Otherwise, mois-
ture may get into the vehicle.
X Remove the valve extractor from the vehi-
cle tool kit.
X Unscrew the valve cap from the valve.
X Unscrew the valve insert from the valve and
release the air.
i Fully deflating the tires can take a few
minutes.
X Screw the valve insert back into the valve.
X Screw the valve cap back on. Emergency spare wheel
367Wheels and tires Z
