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Vehicle care157
The driver is responsible for correct
adjustment of tyre pressure.9 Warning
If the pressure is too low, this can
result in considerable tyre warm-
up and internal damage, leading to tread separation and even to tyre
blow-out at high speeds.
Rear-wheel drive, with twin rear
wheels When inflating the outer tyre, the
inflation tube should be passed
between the two wheels.
Tyre pressure monitoring
system
The Tyre Pressure Monitoring
System (TPMS) uses radio and
sensor technology to check tyre
pressure levels.
Caution
Tyre pressure monitoring system
warns only about low tyre pressure condition and does not replace
regular tyre maintenance by the
driver.
All wheels must be equipped with pressure sensors and the tyres must
have the prescribed pressure.
Notice
In countries where the tyre pressure
monitoring system is legally
required, the use of wheels without
pressure sensors will invalidate the
vehicle type approval.
The TPMS sensors monitor the air
pressure in the tyres and transmit tyre pressure readings to a receiver
located in the vehicle.
Each tyre, including the spare, should
be checked monthly when cold and
inflated to the inflation pressure
recommended on the tyre pressure
label.
Tyre pressures in display
The current tyre pressures can be
shown in the Driver Information
Centre 3 84.
With the vehicle stationary, press
button on end of wiper lever
repeatedly until the tyre pressure
menu is displayed.
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Low tyre pressure condition
A detected low tyre pressure
condition is indicated by illumination
of control indicator w 3 82 and a
corresponding message appears in
the Driver Information Centre.
If w illuminates, stop as soon as
possible and inflate the tyres as
recommended 3 198.
After inflating, driving may be
required to update the tyre pressure
values in the Driver Information
Centre. During this time w may
illuminate.
If w illuminates at lower temperatures
and extinguishes after some driving,
this could be an indicator for getting low pressure. Check tyre pressure.
If the tyre pressure must be reduced
or increased, switch off ignition.
Only mount wheels with pressure
sensors, otherwise the tyre pressure
will not be displayed and w flashes for
several seconds then illuminates continuously together with control
indicator A 3 80 and a
corresponding message appears in
the Driver Information Centre.
A spare wheel or temporary spare
wheel is not equipped with pressure
sensors. TPMS is not operational for these wheels. For the further three
wheels, TPMS remains operational.
Control indicator w and the
corresponding message appears at
each ignition cycle until the tyres are
inflated to the correct tyre pressure.
Driver Information Centre 3 84.
Vehicle messages 3 85.Puncture
A puncture or severely under-inflated
tyre is indicated by illumination of
control indicator w together with C
3 80 and a corresponding message
appears in the Driver Information
Centre.
Tyre pressure 3 198, Tyre repair kit
3 161, Spare wheel 3 166, Wheel
changing 3 164.
Temperature dependency Tyre pressure depends on the
temperature of the tyre. During
driving, tyre temperature and
pressure increase. Therefore it is important to check tyre pressure with
cold tyres.
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Vehicle care159
Relearn function
After changing the wheels, TPMS
needs to recalculate.
With the vehicle stationary, select the tyre pressure menu in the Driver
Information Centre by pressing button
on end of wiper lever. Press and hold button for approx. 3 seconds to
initialise recalculation. A
corresponding message appears in
the Driver Information Centre.
Several minutes of driving may be
required to complete the relearn
process.
If problems occur during the relearn
process, a warning message is
displayed in the Driver Information
Centre.
Driver Information Centre 3 84.
Vehicle messages 3 85.
General information The use of commercially available
liquid tyre repair kits can impair the
function of the system. Factory-
approved tyre repair kits can be used.
Tyre repair kit 3 161.
External high-power radio equipment
could disrupt the TPMS.
Each time the tyres are replaced,
TPMS sensors must be dismounted
and serviced by a workshop.
Fault The TPMS will not function properly if
one or more of the sensors are
missing or inoperable. When the
system detects a malfunction, w
flashes for several seconds and then
illuminates. Additionally a
corresponding message appears in
the Driver Information Centre.Control indicator w and the
corresponding message appear at
each ignition cycle until the problem
is corrected.
Some of the conditions that can
cause these to appear are:
■ One of the tyres has been replaced
with the spare tyre which does not
have a TPMS sensor.
■ The TPMS sensor relearn process was not completed successfully.
Control indicator w and the
corresponding message should
extinguish after successfully
completing the sensor relearn
process.
■ One or more TPMS sensors are missing or damaged. Control
indicator w and the corresponding
message should extinguish when the TPMS sensors are installed and
the sensor relearn process is
performed successfully. Consult a
workshop for service.
■ Replacement tyres or wheels do not match the original equipment
tyres or wheels. Tyres and wheels
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160Vehicle care
other than those recommended
could prevent the TPMS from
functioning properly.
■ Operating electronic devices or being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning
properly, it cannot detect or signal
a low tyre condition. Consult a
workshop for service if control
indicator w illuminates and a
corresponding message appears in the Driver Information Centre.
Tread depth Check tread depth at regular
intervals.
Tyres should be replaced for safety
reasons at a tread depth of 2-3 mm
(4 mm for winter tyres).
For safety reasons it is recommended
that the tread depth of the tyres on
one axle should not vary by more than
2 mm.
The legally permissible minimum
tread depth (1.6 mm) has been
reached when the tread has worn
down as far as one of the tread wear
indicators (TWI). Their position is
indicated by markings on the
sidewall.
If there is more wear at the front than
the rear, swap round front wheels and rear wheels periodically. Ensure that
the direction of rotation of the wheels
is the same as before.
Tyres age, even if they are not used.
We recommend tyre replacement
every 6 years.
Changing tyre and wheel
size
If tyres of a different size than those
fitted at the factory are used, it may be necessary to reprogramme the
speedometer as well as the nominal tyre pressure and make other vehicle modifications.
After converting to a different tyre
size, have the label with tyre
pressures replaced.9 Warning
Use of unsuitable tyres or wheels
may lead to accidents and will
invalidate the vehicle type
approval.
Wheel covers
Wheel covers and tyres that are
factory approved for the respective
vehicle and comply with all of the
relevant wheel and tyre combination requirements must be used.