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Vehicle care231
A detected low tyre pressure
condition is indicated by illumination
of control indicator w 3 89.
If w illuminates, stop as soon as
possible and inflate the tyres as
recommended 3 269.
If w flashes for 60-90 seconds and
then illuminates continuously, there is
a fault in the system. Consult a
workshop.
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
approaching a low tyre pressure
condition. Check tyre pressure.
Vehicle messages 3 97.
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
illuminates continuously.
A spare wheel or temporary spare
wheel is not equipped with pressure
sensors. The tyre pressure
monitoring system is not operational
for these wheels. Control indicator w
illuminates. For the further three
wheels the system remains
operational.
The use of commercially available
liquid tyre repair kits can impair the
function of the system. Factory-
approved repair kits can be used.
Operating electronic devices or being close to facilities using similar wave
frequencies could disrupt the tyre
pressure monitoring system.Each time the tyres are replaced, tyre pressure monitoring system sensors
must be dismounted and serviced. For the screwed sensor: replace
valve core and sealing ring. For
clipped sensor: replace complete
valve stem.
Vehicle loading status Adjust tyre pressure to load condition
according to the tyre information label or tyre pressure chart 3 269, and
select the appropriate setting in the Tyre load menu in the Driver
Information Centre 3 91. This setting
is the reference for the tyre pressure
warnings.
The Tyre Load menu only appears if
the vehicle is in a standstill and the
parking brake is applied. On vehicles
with automatic transmission, the
selector lever must be in P.
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232Vehicle care
Select:● Light for comfort pressure up to
3 people.
● Eco for Eco pressure up to
3 people.
● Max for full load.
Tyre pressure sensor matching
process
Each tyre pressure sensor has a
unique identification code. The
identification code must be matched
to a new wheel position after rotating the wheels or exchanging the
complete wheel set and if one or more
tyre pressure sensors were replaced.
The tyre pressure sensor matching
process should also be performed
after replacing a spare wheel with a
road wheel containing the tyre
pressure sensor.
The malfunction light w and the
warning message or code should
extinguish at the next ignition cycle.
The sensors are matched to the
wheel positions using a relearn tool,
in the following order: left side front
wheel, right side front wheel, right
side rear wheel and left side rear
wheel. The turn signal light at the
current active position is illuminated
until the sensor is matched.
Consult a workshop for service. There
are two minutes to match the first
wheel position, and five minutes
overall to match all four wheel
positions. If it takes longer, the
matching process stops and must be
restarted.
The tyre pressure sensor matching
process is:
1. Apply the parking brake.
2. Turn the ignition on.3. On vehicles with automatic transmission: set the selector
lever to P.
On vehicles with manual
transmission: select neutral.
4. Use MENU on the turn signal
lever to select the Vehicle
Information Menu in the Driver
Information Centre.
5. Turn the adjuster wheel to scroll to
the tyre pressure menu.
6. Press SET/CLR to begin the
sensor matching process. A
message requesting acceptance
of the process should be
displayed.
Press SET/CLR again to confirm
the selection. The horn sounds
twice to indicate the receiver is in
relearn mode.
7. Start with the left side front wheel.
8. Place the relearn tool against the tyre sidewall, near the valve stem.Then press the button to activate
the tyre pressure sensor. A horn
chirp confirms that the sensor
identification code has been
matched to this wheel position.
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Vehicle care2339. Proceed to the right side frontwheel, and repeat the procedure
in Step 8.
10. Proceed to the right side rear wheel, and repeat the procedure
in Step 8.
11. Proceed to the left side rear wheel, and repeat the procedure
in Step 8. The horn sounds twice
to indicate the sensor
identification code has been
matched to the left side rear tyre,
and the tyre pressure sensor
matching process is no longer
active.
12. Turn off the ignition.
13. Set all four tyres to the recommended air pressure level
as indicated on the tyre pressure
label.
14. Ensure the tyre loading status is set according to the selected
pressure 3 91.
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.