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Vehicle care215Tyre pressure monitoringsystem
The tyre pressure monitoring system checks the pressure of all four tyres
once a minute when vehicle speed
exceeds a certain limit.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.
Note
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 current tyre pressures can be
shown in the Vehicle Information
Menu ? in the Driver Information
Centre.
The menu can be selected by
pressing the buttons on the turn
signal lever.
Press MENU to select the Vehicle
Information Menu ? .
Turn the adjuster wheel to select the
tyre pressure monitoring system.
Midlevel display:
The tyre pressure for each tyre is
displayed on its own page.
Uplevel display:
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216Vehicle careThe tyre pressures for all tyres are
displayed on one page.
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 for the warnings.
Temperature dependency 3 213.
A detected low tyre pressure
condition is indicated by the control
indicator w 3 95.
If w illuminates, stop as soon as
possible and inflate the tyres as
recommended 3 253.
If w flashes for 60-90 seconds then
illuminates continuously, there is a
fault in the system. Consult a
workshop.
After inflating, some 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 driving, this
could be an indicator for approaching a low tyre pressure condition. Check
tyre pressure.
Vehicle messages 3 103.
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 tyres. Control indicator w
illuminates. For the further three
tyres, 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 to the tyre information label
or tyre pressure chart 3 253, and
select the appropriate setting in the
menu Tyre Load in the Driver
Information Centre, Vehicle
Information Menu 3 97 . This setting is
the reference for the tyre pressure warnings.
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Vehicle care217The menu Tyre Load 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.
Midlevel display:
Select ● LO for comfort pressure up to
three people.
● ECO for Eco pressure up to
three people.
● Hi for full loading.
Uplevel display:
Select ● Light for comfort pressure up to
three people.
● Eco for Eco pressure up to
three people.
● Max for full loading.
Tyre pressure sensor matching process
Each TPMS 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 a 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 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.
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218Vehicle care3. On vehicles with automatictransmission: set the selector
lever to P.
On vehicles with manual
transmission automated: Keep
brake pedal depressed. Move and hold the selector lever for five
seconds to position N until P is
displayed in the Driver
Information Centre. P indicates
that the tyre pressure sensor
matching process can be started.
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.
Midlevel display:
Uplevel display:
6. Press SET/CLR to begin the
sensor matching process. A
message requesting acceptance
of the process should be
displayed.
7. Press SET/CLR again to confirm
the selection. The horn sounds
twice to indicate that the receiver
is in relearn mode.
8. Start with the left side front wheel.
9. 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.
10. Proceed to the right side front wheel, and repeat the procedure
in Step 9.
11. Proceed to the right side rear wheel, and repeat the procedure
in Step 9.
12. Proceed to the left side rear wheel, and repeat the procedure
in Step 9. The horn sounds twice
to indicate that the sensor
identification code has been
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Vehicle care219matched to the left side rear
wheel, and the tyre pressure
sensor matching process is no
longer active.
13. Turn off the ignition.
14. Set all four tyres to the recommended air pressure level
as indicated on the tyre pressure
information label.
15. Ensure the tyre loading status is set according to the selected
pressure 3 97.
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.
Tyres age, even if they are not used.
We recommend tyre replacement
every six 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 to make other
vehicle modifications.
After converting to a different tyre
size, have the label with tyre
pressures replaced.Caution
When converting to wheels with 14 inch diameter, the ground
clearance will be reduced. This
must be considered when passing
over obstacles.
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.