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Vehicle care243
Remove the cover.
If equipped with tyre repair kit,
remove the complete box.
Fuse assignmentsNo.Circuit1–2Trailer outlet3Parking assist4Selective catalytic reduction
system5–6–7Power seat8–9Selective catalytic reduction
system10Nitrogen oxide sensor11Trailer module, trailer socket12Trailer module13Trailer outlet14–15–
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246Vehicle care
Incorrect 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 the engine identifier code.
Engine data 3 274.
2. Identify the respective tyre.
The tyre pressure tables show all possible tyre combinations 3 283.
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.
If the tyre pressure must be reduced
or increased on a vehicle with tyre
pressure monitoring system, switch
off ignition. After adjusting tyre
pressure, switch on ignition and
select the appropriate setting on the
page Tyre load in the Driver
Information Centre, 3 115.
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 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.
The current tyre pressures can be
shown in the Vehicle Information
Menu in the Driver Information
Centre.
The menu can be selected by the
buttons on the turn signal lever.
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Vehicle care247
Press the MENU button to select the
Vehicle Information Menu X .
Turn the adjuster wheel to select the
tyre pressure monitoring system.
System status and pressure warnings
are displayed by a message with the
corresponding tyre flashing in the
Driver Information Centre.
A detected low tyre pressure
condition is indicated by the control
indicator w 3 113.
If w illuminates, stop as soon as
possible and inflate the tyres as
recommended 3 283.
After inflating, driving may be
required to update the tyre pressure
values in the DIC. During this time w
may illuminate.
If w illuminates up at lower
temperatures and extinguishes after
some driving, this could be an
indicator for getting low pressure.
Check tyre pressure.
Vehicle messages 3 121.
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.
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248Vehicle care
The use of commercially available
liquid tyre repair kits can impair the
function of the system. Factory-
approved repair kits can be used.
External high-power radio equipment
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 labelor tyre pressure chart 3 283, and
select the appropriate setting in the
menu Tire Load in the Driver
Information Centre, Vehicle
Information Menu 3 115.
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, the vehicle
must be stationary for approx.
20 minutes, before the system
recalculates. The following relearn
process takes up to 10 minutes of
driving with a minimum speed of
12 mph. In this case $ can be
displayed or pressure values can
swap in the Driver Information Centre.
If problems occur during the relearn
process, a warning message is
displayed in the Driver Information
Centre.
Temperature dependency Tyre pressure depends on the
temperature of the tyre. During
driving, tyre temperature and
pressure increase.
The tyre pressure value displayed in
the Driver Information Centre shows
the actual tyre pressure. Therefore it
is important to check tyre pressure
with cold tyres.
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).