The rolling circumference can change:
— If the tyre pressure has been changed.
— If the tyre pressure is too low.
— If the tyre has structural damage.
— If the vehicle is loaded more heavily on
one side.
— If snow chains have been fitted.
— If a temporary spare wheel has been fit-
ted.
— If one wheel per axle has been changed.
The Tyre Pressure Loss Indicator may react
with a delay or not display anything at all in
the event of a sporty driving style, when driv-
ing on snow-covered or icy roads or unpaved
roads or when driving with snow chains.
The tyre monitoring system indicates
a change in rolling circumference of the tyres
with the warning lamp in the instrument
cluster.
The recommended tyre pressure for the fac-
tory-fitted tyres is indicated on the tyre pres-
sure sticker on the driver's door pillar
→ page 332.
The tyre pressure of all tyres including the
spare wheel or temporary spare wheel must
be checked monthly on a cold tyre and corre-
spond to the vehicle manufacturer's specifi-
cations on the tyre pressure sticker. If the
tyre size of the mounted tyres differs from
the specifications on the type plate or tyre
pressure sticker, the correct tyre pressure
must be determined.
The Tyre Pressure Loss Indicator does not re-
move the need for regular maintenance and
inspection of tyres. The driver is responsible
for ensuring the correct tyre pressure is
maintained at all times, even if the Tyre Pres-
sure Loss Indicator does not give any warning
that the tyre pressure is too low.
The Tyre Pressure Loss Indicator also can dis-
play a malfunction in conjunction with the
warning lamp. If the Tyre Pressure Loss Indi-
cator is malfunctioning, the warning lamp
flashes for about a minute after the vehicle’s
drive system has been activated and then
stays continuously lit.
If the Tyre Pressure Loss Indicator shows
a malfunction, tyre pressure cannot be moni-
tored correctly. The malfunctioning of the
Tyre Pressure Loss Indicator can have various
causes, e.g. due to replacing a wheel or tyre.
When a wheel or tyre has been replaced,
a check needs to be made whether the
warning lamp is indicating a system malfunc-
tion → page 327 to ensure that the Tyre
Pressure Loss Indicator is functioning proper-
ly.
Synchronising the Tyre Pressure Loss Indica-
tor
The Tyre Pressure Loss Indicator must be re-
synchronised under the following conditions:
— If the tyre pressures have been changed.
— If one or more wheels have been changed.
— If the wheels are swapped over, e.g. from
front to rear.
The Tyre Pressure Loss Indicator may only be
re-synchronised if all the tyres have been fil-
led at the correct tyre pressure when meas-
ured on a cold tyre. To measure the cold tyre
pressure, the vehicle must have been station-
ary for 3 hours or driven only a few kilome-
tres at a slow speed during this time.
After a warning about the tyre pres-
sure being too low, switch the ignition
off and then back on again. The Tyre Pressure
Loss Indicator can only then be re-synchron-
ised.
1.
Switch on the ignition.
2.
Switch on Infotainment system if neces-
sary.
3.
Touch
Vehicle
in the Infotainment sys-
tem.
4.
Touch
Vehicle
(left).
5.
Touch
Tyres
.
6.
Touch
SET
.
7.
When all four tyre pressures correspond
to the required values, touch
OK
.
326
Wheels and tyres
