Important safety notes
It is the driver's responsibility to set the tyre
pressure to the recommended cold tyre pres-
sure suitable for the operating situation
(Y page 458). Note that the correct tyre pres-
sure for the current operating situation must
first be taught-in to the tyre pressure monitor. If there is a substantial loss of pressure, the
warning threshold for the warning message is aligned to the reference values taught-in.
Restart the tyre pressure monitor after
adjusting to the cold tyre pressure
(Y page 462). The current pressures are
saved as new reference values. This will
ensure that a warning message will only
appear if the tyre pressure drops significantly.
The tyre pressure monitor does not warn you
of an incorrectly set tyre pressure. Observe
the notes on the recommended tyre pressure
(Y page 458).
The tyre pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tyre 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 manoeuvres.
The tyre pressure monitor has a yellow warn-
ing lamp in the instrument cluster for indicat- ing a pressure loss or malfunction. Dependingon how the warning lamp flashes or lights up,
a tyre pressure that is too low or a malfunc-
tion in the tyre pressure monitor is indicated:
R if the warning lamp is lit continuously, the
tyre pressure on one or more tyres is sig-
nificantly too low. The tyre pressure moni-
tor is not malfunctioning.
R if the warning lamp flashes for around a
minute and then remains lit constantly, the
tyre pressure monitor is malfunctioning.
In addition to the warning lamp, a message
appears in the multifunction display. Observe
the information on display messages
(Y page 367).
It may take up to ten minutes for a malfunc-
tion of the tyre pressure monitor to be indi-
cated. A malfunction will be indicated by the tyre pressure warning lamp flashing for
approximately one minute and then remain-
ing lit. When the fault has been rectified, the
tyre pressure warning lamp goes out after you
have driven for a few minutes.
The tyre pressure values indicated by the on- board computer may differ from those meas-
ured at a filling station using a pressure
gauge. The tyre pressures shown by the on-
board computer refer to those measured at
sea level. At high altitudes, the tyre pressure
values indicated by a pressure gauge are
higher than those shown by the on-board
computer. In this case, do not reduce the tyre
pressures.
The operation of the tyre pressure monitor
can be affected by interference from radio
transmitting equipment (e.g. radio head-
phones, two-way radios) that may be being
operated in or near the vehicle.
Checking the tyre pressure electroni-
cally X
Make sure that the key is in position 2in the
ignition lock (Y page 187).
X Press the òbutton on the steering
wheel to call up the list of menus.
X Press 9or: on the steering wheel
to select the Service Servicemenu.
X Press the abutton.
X Press 9or: to select Tyre pres‐
Tyre pres‐
sure
sure.
X Press the abutton.
The current tyre pressure for each wheel
will be displayed in the multifunction dis-
play.
If the vehicle was parked for longer than
20 minutes, the following message appears:
Tyre pressures will be displayed Tyre pressures will be displayed
after a few minutes of driving after a few minutes of driving.
After a teach-in period, the tyre pressure
monitor automatically detects new wheels or
new sensors. As long as a clear allocation of
the tyre pressure values to the individual
wheels is not possible, the Tyre pressure Tyre pressure Tyre pressure
461Wheels and tyres Z
monitor active
monitor active
message is shown instead
of the tyre pressure display. The tyre pres-
sures are already being monitored.
If an emergency spare wheel is fitted, for a
few minutes the system may continue to
show the tyre pressure of the wheel that has
been removed. If this occurs, note that the
value displayed for the position where the
spare wheel is fitted is not the same as the
current tyre pressure of the emergency spare wheel.
Warning messages of the tyre pressure
monitor If the tyre pressure monitor detects a pres-
sure loss in one or more tyres, a warning mes-
sage is shown in the multifunction display.
The yellow tyre pressure warning lamp then
lights up.
R If the Please correct tyre pressure
Please correct tyre pressure
message appears in the multifunction dis-
play, the tyre pressure in at least one tyre is
too low. The tyre pressure must be correc-
ted when the opportunity arises.
R If the Check tyre(s)
Check tyre(s) message appears in
the multifunction display, the tyre pressure in at least one tyre has dropped signifi-
cantly. The tyres must be checked.
R If the Warning tyre defect Warning tyre defect message
appears in the multifunction display, the
tyre pressure in at least one tyre has drop- ped suddenly. The tyres must be checked.
Observe the instructions and safety notes in
the display messages in the "Tyres" section
(Y page 367).
If the wheel positions on the vehicle are inter-
changed, the tyre pressures may be displayed
for the wrong positions for a short time. After a few minutes of driving, this is rectified and
the tyre pressures are displayed for the cor-
rect positions.
Restarting the tyre pressure monitor When you restart the tyre pressure monitor,
all existing warning messages are deleted and the warning lamps go out. The monitor uses
the currently set tyre pressures as the refer-
ence values for monitoring. In most cases, the
tyre pressure monitor will automatically
detect the new reference values after you
have changed the tyre pressure. However,
you can also set reference values manually as described here. The tyre pressure monitor
then monitors the new tyre pressure values.
X Use the table on the inside of the fuel filler
flap to ensure that the tyre pressure is set
correctly in all four tyres for the current
operating conditions.
Also observe the notes in the section on
tyre pressures (Y page 458).
X Make sure that the key is in position 2in the
ignition lock (Y page 187).
X Press the òbutton on the steering
wheel to call up the list of menus.
X Press 9or: on the steering wheel
to select the Service Servicemenu.
X Press the abutton.
X Press 9or: to select Tyre pres‐
Tyre pres‐
sure
sure.
X Press the abutton.
The current tyre pressure for each wheel or
the Tyre pressures will be dis‐
Tyre pressures will be dis‐
played played after
aftera
afew
few minutes
minutes of
ofdriv‐
driv‐
ing
ing message will be displayed in the mul-
tifunction display.
X Press the :button.
The Use current pressures as new
Use current pressures as new
reference values
reference values message appears in
the multifunction display.
If you wish to confirm the restart: X Press the abutton.
The Tyre press. monitor restarted
Tyre press. monitor restarted
message appears in the multifunction dis-
play.
After you have driven for a few minutes, the system checks whether the current tyre
pressures are within the specified range.
The new tyre pressures are then accepted
as reference values and monitored. 462
Tyre pressureWheels and tyres
