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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
warning lamp in the instrument cluster for
indicating a pressure loss or malfunction.
Whether the warning lamp flashes or lights up
indicates 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
significantly 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
message appears in the multifunction
display.
Further information can be found on
(Y page 269).
If the tire pressure monitor is malfunctioning,
it may take more than ten minutes for the tire
pressure warning lamp to infor myou of the
malfunction by flashing for approximately one
minute and then remaining lit. When the
malfunction has been rectified, the tire
pressure warning lamp goes out after a few
minutes of driving.
The tire pressure values indicated by the on-
board computer may differ from those
measured at a gas station with a pressure
gauge. The tire pressures shown by the on-
board computer refer to those measured at
sea level. At high altitudes, the tire pressure
values indicated by a pressure gauge are
higher than those shown by the on-board
computer. In this case, do not reduce the tire
pressures.
The operation of the tire pressure monitor can
be affected by interference from radio
transmitting equipment (e.g. radio
headphones, two-way radios) that may be
being operated in or near the vehicle. Checking the tire pressure
electronically X
Make sure that the SmartKey is in position
2in the ignition lock (Y page 165).
X Press the 0002or0005 button on the
steering wheel to select the Service menu.
X Press the 0003or0004 button to select
Tire Pressure .
X Press the 000Bbutton.
The current tire pressure of each tire is
shown in the multifunction display.
If the vehicle has been parked for over
20 minutes ,the Tire pressures will be
displayed after driving a few
minutes message appears.
After a teach-in process, the tire pressure
monitor automatically detects new wheels or
new sensors. As long as a clear allocation of
the tire pressure value to the individual
wheels is not possible, the Tire Pressure Monitor Active display message is shown
instead of the tire pressure display. The tire
pressures are already being monitored.
i If an emergency spare wheel is mounted,
the system may continue to show the tire
pressure of the wheel that has been
removed for a few minutes. If this occurs,
note that the value displayed for the
position where the spare wheel is mounted
is not the same as the current tire pressure
of the emergency spare wheel.
Tire pressure monitor warning
messages If the tire pressure monitor detects a pressure
loss in one or more tires, a warning message
is shown in the multifunction display and the
yellow tire pressure monitor warning lamp
comes on.
R If the Correct Tire Pressure message
appears in the multifunction display, the
tire pressure in at least one tire is too low 354
Tire pressureWheels and tires
Page 357 of 394

and must be corrected at the next
opportunity.
R If the Check Tires message appears in the
multifunction display, the tire pressure in
one or more tires has dropped significantly
and the tires must be checked.
R If the Warning Tire Malfunction message appears in the multifunction
display, the tire pressure in one or more
tires has dropped suddenly and the tires
must be checked.
Observe the instructions and safety notes in
the display messages in the "Tires" section
(Y page 269).
i If the wheel positions on the vehicle are
rotated, the tire pressure smay be
displayed for the wrong positions for a
short time. This is rectified after a few
minutes of driving, and the tire pressures
are displayed for the correct positions.
Restarting the tire pressure monitor When you restar
tthe tire pressure monitor,
all existing warning messages are deleted and
the warning lamps go out. The monitor uses
the currently set tire pressures as the
reference values for monitoring. In most
cases, the tire pressure monitor will
automatically detect the new reference
values after you have changed the tire
pressure. However, you can also define
reference values manually as described here.
The tire pressure monitor then monitors the
new tire pressure values.
X Set the tire pressure to the value
recommended for the corresponding
driving situation on the Tire and Loading
Information placard on the driver's side
B-pillar (Y page 348).
Additional tire pressure values for different
loads can also be found on the tire pressure
table on the inside of the fuel filler flap
(Y page 348).
X Make sure that the tire pressure is correct
on all four wheels. X
Make sure that the SmartKey is in position
2in the ignition lock.
X Press the 0002or0005 button on the
steering wheel to select the Service menu.
X Press the 0003or0004 button to select
Tire Pressure .
X Press the 000Bbutton.
The multifunction display shows the
current tire pressure for the individual tires
or the Tire pressures will be displayed after driving a few
minutes message.
X Press the 0004button.
The Use Current Pressures as New Reference Values message appears in
the multifunction display.
If you wish to confirm the restart:
X Press the 000Bbutton.
The Tire Press. Monitor Restarted message appears in the multifunction
display.
After driving for a few minutes, the system
checks whether the current tire pressures
are within the specified range. The new tire
pressures are then accepted as reference
values and monitored.
If you wish to cancel the restart:
X Press the 0007button.
The tire pressure values stored at the last
restart will continue to be monitored. Loading the vehicle
Instruction labels for tires and loads
G
WARNING
Overloaded tires can overheat, causing a
blowout. Overloaded tires can also impair the
steering and driving characteristics and lead
to brake failure. There is a risk of accident.
Observe the load rating of the tires. The load
rating must be at least half of the GAWR of Loading the vehicle
355Wheels and tires
Z
Page 370 of 394

Components damaged in this way may fail
unexpectedly. There is a ris
kofanaccident.
Do not use power washers with circula rjet
nozzles to clean the vehicle. Have damaged
tires or chassis componentsr eplaced
immediately. Mounting
awheel
Preparing the vehicle X
Stop the vehicle on solid, non-slippery and
level ground.
X Apply the parking brake.
X Bring the front wheels into the straight-
ahead position.
X Shift the transmission to position P.
X Switch off the engine.
X Vehicles without KEYLESS-GO: remove
the SmartKey from the ignition lock.
X Vehicles with KEYLESS-GO: open the
driver's door.
The on-board electronics now have status
0.T his is the same as the SmartKey having
been removed.
X Vehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock
(Y page 165).
X If included in the vehicle equipment,
remove the tire-change tool kit from the
vehicle (Y page 328).
X Secure the vehicle to prevent it from rolling
away. Securing the vehicle to prevent it from
rolling away If your vehicle is equipped with a wheel chock,
it can be found in the tire-change tool kit
(Y
page 328).
The folding wheel chock is an additional
safety measure to prevent the vehicle from
rolling away, for example when changing a
wheel.
X Fold both plates upwards 0002.
X Fold out lower plate 0003.
X Guide the lugs on the lower plate fully into
the openings in base plate 0023. Securing the vehicle on level ground (example:
Coupe)
X
On level ground: place chocks or other
suitable items under the front and rear of
the wheel that is diagonally opposite the
wheel you wish to change. 368
Changing
awheelWheels and tires