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Vehicle care255Incorrect tyre pressures will impair
safety, vehicle handling, comfort and
fuel economy and will increase tyre
wear.
Tyre pressures differ depending on
various options. For the correct tyre
pressure value, follow the procedure
below:
1. Identify drive axle and body style.2. Identify the engine identifier code.
Engine data 3 284.
3. Identify the respective tyre.
The tyre pressure tables show all
possible tyre combinations 3 291.
For the tyres approved for your
vehicle, refer to the EEC Certificate of Conformity provided with your vehicle
or other national registration
documents.
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.
9 Warning
For specific tyres the
recommended tyre pressure as
shown in the tyre pressure table may exceed the maximum tyre
pressure as indicated on the tyre.
Never exceed the maximum tyre
pressure as indicated on the tyre.
After adjusting tyre pressure, select
the according tyre loading setting on
the page Tyre load in the Driver
Information Centre 3 110.
Temperature dependency The tyre pressure depends on the
temperature of the tyre. During
driving, tyre temperature and
pressure increase. Tyre pressure
values provided on the tyre
information label and tyre pressure
chart are valid for cold tyres, which means at 20 °C.
The pressure increases by nearly
1.5 psi for a 10 °C temperature
increase. This must be considered
when warm tyres are checked.
The tyre pressure value displayed in
the Driver Information Centre shows
the real tyre pressure. A cooled down tyre will show a decreased value,
which does not indicate an air leak.
Tyre pressure monitoring system
The tyre pressure monitoring system
checks the pressure of all four wheels once a minute when vehicle speed
exceeds a certain limit.Caution
Tyre pressure monitoring system
warns just about low tyre pressure condition and does not replace
regular tyre maintenance by the
driver.
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256Vehicle careAll 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 operating permit.
Select the Tyre pressure monitoring
page under the Info Menu in the
Driver Information Centre 3 110.
System status and pressure warnings
are displayed by a message
indicating the corresponding tyre in the Driver Information Centre.
The system considers the tyre
temperature and the tyre loading
setting for the warnings.
Tyre loading setting, see below in this chapter.
Temperature dependency 3 254.
Baselevel display: If the pressure of a
tyre decreases significantly, the
respective tyre pressure value is displayed inverted.
Uplevel display: Tyre pressure values in normal range are shown in greenletters. If the pressure of a tyre
decreases significantly, the
respective value will turn its colour to
amber.
A detected low tyre pressure
condition is indicated by the control
indicator w 3 108.
If
w illuminates, stop as soon as
possible and inflate the tyres as
recommended 3 291.
Ensure that vehicle loading status
matches selected tyre pressure.
Vehicle loading status, see below in
this chapter.
After inflating, some driving may be
required to update the tyre pressure
values in the Driver Information
Centre. During this time w may
continue to 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 3 121.
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
Page 259 of 313

Vehicle care257illuminates. 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 the
clipped sensor, replace complete
valve stem.
Vehicle loading status Adjust tyre pressure to load condition
according tyre information label or
tyre pressure chart 3 291, and select
the appropriate setting in Tyre Load
within the vehicle information menu
3 110. This setting determines the
reference pressures for the tyre
pressure warnings.The Tyre Load menu only appears
when the vehicle is at a standstill and the parking brake is applied. On
vehicles with automatic transmission
the selector lever must be in P.
Select:
● Light for comfort pressure up to
3 people.
● Eco for Eco pressure up to
3 people.
● Max for full loading.
Auto learn function After changing wheels or wheel
positions the vehicle must be
stationary for approx. 20 minutes,
before the system recalculates. The
following relearn process takes up to
10 minutes of driving in a speed range
of 25 to 60 mph. Avoid to drive outside
of this range for a longer time. If
possible, use a country road or similar which allows continuous driving.
During relearn process $ can be
displayed or pressure values can
swap in the Driver Information Centre.
If problems occur during the relearn
process, a failure message is
displayed in the Driver Information
Centre. w will flash for 60 seconds
and then illuminate continuously.
If this happens, repeat learning
process. Keep your vehicle stationary for approx. 20 minutes and then drive
again for 10 minutes as described
above.
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).
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258Vehicle careFor 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
remains the same.
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
nominal tyre pressure and make
other vehicle modifications.
After converting to a different tyre
size, have the label with tyre
pressures replaced and the tyre
pressure monitoring system
reinitialised 3 255.9 Warning
The use of unsuitable tyres or
wheels may lead to accidents and will invalidate the vehicle
operating permit.
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.
If the wheel covers and tyres used are
not factory approved, the tyres must
not have a rim protection ridge.
Wheel covers must not impair brake
cooling.9 Warning
Use of unsuitable tyres or wheel
covers could lead to sudden
pressure loss and thereby
accidents.
Vehicles with steel wheels: When
using locking wheel nuts, do not
attach wheel covers.
Page 261 of 313
Vehicle care259Tyre chains
Tyre chains are only permitted on the
front wheels.
Always use fine mesh chains that add no more than 10 mm to the tyre tread
and the inboard sides (including chain lock).
9 Warning
Damage may lead to tyre blowout.
Tyre chains are only permitted on
tyres of size 215/60 R16, 215/55 R17 ,
225/55 R17 and 235/45 R18.
Temporary spare wheel
The use of tyre chains is not permitted on the temporary spare wheel.
Tyre repair kit
Minor damage to the tyre tread can be
repaired with the tyre repair kit.
Do not remove foreign bodies from
the tyres.
Tyre damage exceeding 4 mm or that is at tyre's side wall cannot be
repaired with the tyre repair kit.9 Warning
Do not drive faster than 50 mph.
Do not use for a lengthy period.
Steering and handling may be
affected.
Two types of tyre repair kit are
available:
● Type 1 indicated by the on/off
switch at the top of the
compressor.
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260Vehicle care●Type 2 indicated by the on/off
switch at the side of the
compressor.
If vehicle has a flat tyre:
Apply the parking brake and engage first gear, reverse gear or P.
On vehicles with audio speaker
system, the tyre repair kit is stowed together with the tools.
On other versions, the tyre repair kit
is stored in a bag.
Loosen the screw and remove the
bag.
Take the sealant bottle and the
compressor out of the box.
1. Remove the electrical connection cable and air hose from the
stowage compartments on the
underside of the compressor.
Page 263 of 313
Vehicle care261
2.Type 1: screw the compressor air
hose to the connection on the
sealant bottle and fit the sealant
bottle into the retainer on the
compressor.
Type 2: remove screw plug from
the compressor and from the
sealant bottle. Screw the bottle on the compressor without removing
the tinfoil from the bottle.
3. Set the compressor near the tyre in such a way that the sealant
bottle is upright.
4. Unscrew valve cap from defective
tyre.
5. Type 1: screw the filler hose to the
tyre valve.
Type 2: remove protection cap
from filler hose and screw the filler
hose to the tyre valve. The air
release valve must be closed (turn clockwise).
6. The switch on the compressor must be set to J.
7. Connect the compressor plug to the power outlet or cigarette
lighter socket.
To avoid discharging the battery, we recommend running the
engine.
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262Vehicle care
8. Set the rocker switch on thecompressor to I. The tyre is filled
with sealant.
9. The compressor pressure gauge briefly indicates up to 6 bar whilstthe sealant bottle is emptying
(approx. 30 seconds). Then the
pressure starts to drop.
10. All of the sealant is pumped into the tyre. Then the tyre is inflated.
11. The prescribed tyre pressure should be obtained within
10 minutes. Tyre pressure
3 291 . When the correct pressure
is obtained, switch off the
compressor.
Do not run the compressor longer than 10 minutes.
Type 1: if the tyre pressure is not
obtained within 10 minutes,
remove the tyre repair kit. Move
the vehicle one tyre rotation.
Reattach the tyre repair kit and
continue the filling procedure for
10 minutes. Check tyre pressure
once more. If the prescribed tyre
pressure is still not obtained, the
tyre is too badly damaged. Seek
the assistance of a workshop.
Drain excess tyre pressure with
the button over the pressure indicator.
Depending on version the button
can be located on the air hose.
Type 2: remove tyre repair kit and
drive immediately up to 6 miles,
but not longer than 10 minutes.
Check tyre pressure once more. If
the tyre pressure is not obtained,
reattach the tyre repair kit and
continue the filling procedure for
10 minutes. If the prescribed tyre pressure is still not obtained, the
tyre is too badly damaged. Seek
the assistance of a workshop.
If the pressure is obtained, correct to the prescribed tyre pressure by
using the compressor to increase
or decrease by opening the air