X
Press the
a
button.
The tyre pressure values stored at the last
restart will continue to be monitored.
Tyre pressure monitor
General notes
If a tyre pressure monitor system is fitted, the
vehicle's wheels have sensors fitted that moni-
tor the tyre pressures in all four tyres. The tyre
pressure monitor warns you if the pressure
drops in one or more of the tyres. The tyre pres-
sure monitor only functions if the corresponding
sensors are fitted to all wheels.
Information on tyre pressures is shown in the
multifunction display. After a few minutes of
driving, the current tyre pressure of each tyre is
shown in the
Serv.
Serv.
menu of the multifunction
display, see illustration (example).
For further information on displaying this mes-
sage, refer to the "Checking the tyre pressure
electronically" section (
Y
page 411).
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 408). 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 warn-
ing 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 412). The current pres-
sures 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 408).
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 warning
lamp in the instrument cluster for indicating a
pressure loss or malfunction. Depending 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 warning lamp is lit continuously, the tyre
pressure on one or more tyres is significantly
too low. The tyre pressure monitor is not mal-
functioning.
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 330).
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 tyre pres-
sure warning lamp flashing for approximately
one minute and then remaining lit. When the
fault has been rectified, the tyre pressure warn-
ing 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 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. radio 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 (
Y
page 158).
X
Press the
=
or
;
button on the steering
wheel to select the
Service
Service
menu.
Tyre pressure
411
Wheels
and
tyres
Z
