RUN FLAT TYRES
Principle of operation
Standard tyre
Wheel rim position with correct
tyre pressure
A
Wheel rim position with
insufficient tyre pressure
B
TyreC
Run flat tyre Wheel rim position with correct
tyre pressure
A
Wheel rim position with
insufficient tyre pressure
B
TyreC
Reinforced sidewall
D When a standard tyre experiences a
drastic loss of inflation pressure, the rim
of the wheel brings the full weight of the
vehicle to bear on the collapsed sidewalls.
You can barely manoeuvre the vehicle
and the tyre is destroyed.
Run flat tyres have sturdy, reinforced
sidewalls that support the rim should the
tyre suffer a loss of inflation pressure.
What to do if a run flat tyre has
a puncture
Due to the run-flat properties of these
tyres, you may not notice any tyre defect.
Your vehicle is equipped with a tyre
pressure monitoring system that alerts
you to any drop in tyre pressure. See
Technical specifications
(page 168).
In the event of a tyre defect:
• immediately slow down to a maximum
speed of 80 km/h (50 mph)
• avoid sudden or erratic braking and
steering manoeuvres and be
especially careful negotiating bends
• do not drive more than 80 kilometres
(50 miles) after the defect is detected
• have the defective tyre replaced as
soon as possible.
Replacing run flat tyres WARNINGS
Make sure that the workshop is
aware that your vehicle is equipped
with special run flat tyres.
Never repair or reuse run flat tyres
that are damaged or have been
driven on run flat.
If a run flat tyre has to be replaced, have
the respective wheel rim inspected for
any damage.
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Vehicles with stability control
(ESP)
Vehicles with stability control (ESP) may
exhibit some unusual driving
characteristics which can be avoided by
switching the system off. See
Using
stability control (page 113).
TYRE PRESSURE
MONITORING SYSTEM WARNINGS
The system does not relieve you of
your responsibility to regularly check
the tyre pressures.
The system will only provide a low
tyre pressure warning. It will not
inflate the tyres.
Do not drive on significantly
under-inflated tyres. This may cause
the tyres to overheat and fail.
Under-inflation reduces fuel efficiency,
tyre tread life and may also affect your
ability to drive the vehicle safely. CAUTIONS
Do not bend or damage the valves
when you are inflating the tyres.
Have tyres installed by properly
trained technicians.
The Deflation Detection System will alert
you if there is a change of air pressure in
any tyre. It does this by using the ABS
sensors to detect the rolling
circumference of the wheels. When the
circumference changes, this indicates low
pressure in a tyre, a warning message is
displayed in the information display and
the message indicator will illuminate. See
Information messages
(page 73).Apart from a too low tyre pressure or a
damaged tyre, the following situations can
affect the rolling circumference:
•
Vehicle load is uneven.
• When using a trailer or travelling up
and down an incline.
• Using snow chains.
• Driving on soft surfaces such as snow
or mud.
Note:The system will still function
correctly, but there may be an increased detection time.
If a low pressure warning message is
displayed in the information display, check
the tyre pressures as soon as possible
and inflate them to the recommended
pressure. See Technical
specifications (page 168).
If this happens frequently, have the cause
determined and rectified as soon as
possible.
System reset
Note:
Do not reset the system when the
vehicle is moving.
Note:You should reset the system
following any adjustment to the tyre pressures or any changing of tyres.
Note:Turn the ignition on.
Type 2 instrument cluster
1. Using the multifunction lever, navigate
to'SET' > T. Pres.
2. Press and hold the SET/RESET
button until the message Tyre
Pressure set appears.
Type 3 instrument cluster
1. Using the multifunction lever, navigate
tohold 'SET' to set Tyre Pres.
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