For further information on displaying this mes-
sage, refer to the "Checking the tyre pressure
electronically" section (
Y
page 240).
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 238). Note that the correct tyre pres-
sure for the current operating situation must
first be learnt by the tyre pressure monitor. If a
substantial loss of pressure occurs, the warning
threshold for the warning message is aligned to
the learnt reference values. Restart the tyre
pressure monitor after adjusting to the cold tyre
pressure (
Y
page 241). The current pressures
are saved as new reference values. This ensures
that a warning message appears only 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 238).
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 this event,
bring the vehicle to a halt by braking carefully.
Avoid abrupt steering manoeuvres.
The tyre pressure monitor has a yellow
h
warning lamp on the instrument cluster for indi-
cating a pressure loss or malfunction. Depend-
ing on how the warning lamp flashes or lights up,
a tyre pressure that is too low or a malfunction in
the tyre pressure monitor is indicated:
R
if the
h
warning lamp is lit continuously,
the tyre pressure on one or more tyres is sig-
nificantly too low. The tyre pressure monitor
is not malfunctioning.
R
if the
h
warning lamp flashes for around a
minute and then remains lit constantly, the
tyre pressure monitor is malfunctioning.
In addition to the
h
warning lamp, a message
appears in the multifunction display. Observe
the information on display messages
(
Y
page 150).
It may take up to ten minutes for a malfunction
of the tyre pressure monitor to be indicated. A
malfunction will be indicated by the
h
tyre
pressure warning lamp flashing for approx-
imately one minute and then remaining lit. When
the fault has been rectified, the
h
tyre pres-
sure warning lamp goes out after driving 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 com-
puter refer to those measured at sea level. At
high altitudes, the tyre pressure values indica-
ted 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 transmit-
ting equipment (e.g. cordless headphones, 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 2 in the
ignition lock.
X
Press the
=
or
;
button on the steering
wheel to select the
Serv.
Serv.
menu.
X
Press the
9
or
:
button to select
Tyre pressure
Tyre pressure
.
X
Press the
a
button.
The multifunction display shows the current
tyre pressure of each wheel.
If the vehicle has been parked for over
20 minutes, the
Tyre pressures will be
Tyre pressures will be
displayed
displayed after a
after a few
few minutes
minutes of
of driv‐
driv‐
ing
ing
message appears.
After a teach-in period, the tyre pressure moni-
tor 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
Tyre pressure
pressure monitor
monitor active
active
display message is shown instead of the tyre
pressure display. The tyre pressures are already
being monitored.
If a spare wheel is fitted, the system may con-
tinue to show the tyre pressure of the wheel that
has been removed for a few minutes. Please
note that in this case, the value displayed for the
replaced wheel does not indicate the current
tyre pressure of the spare wheel.
Warning messages of the tyre pressure
monitor
If the tyre pressure monitor detects a pressure
loss in one or more tyres, a warning message is
shown on the multifunction display. The yellow
h
tyre pressure warning lamp then lights up.
240
Tyre pressure
Wheels
and
tyres
