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240Vehicle care
Fuse assignmentsNo.Circuit1–2Trailer outlet3Parking assist4Selective catalytic reduction
system5–6–7Power seat8–9Selective catalytic reduction
system10Nitrogen oxide sensor11Trailer module, trailer socket12Trailer module13Trailer outlet14–15–No.Circuit16Inside mirror, rear view camera17Power outlet18–19Steering wheel heating20Sunblind21Heated front seats22–23–24Selective catalytic reduction
system25–26–27–28–29–30–
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Vehicle care243
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, 3 114.
Tyre pressure monitoring system
The tyre pressure monitoring system
(TPMS) 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.
Notice
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
(DIC).
The menu can be selected by the
buttons on the turn signal lever.
Press the MENU button to select the
Vehicle Information Menu X .
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244Vehicle care
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
DIC.
A detected low tyre pressure
condition is indicated by the control
indicator w 3 111.
If w illuminates, stop as soon as
possible and inflate the tyres as
recommended 3 282.
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 DIC. During this time w
may illuminate.
If w illuminates at lower temperatures
and extinguishes after some driving,
this could be an indicator for getting
low pressure. Check tyre pressure.
Vehicle messages 3 120.
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 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.
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 3 282, and
select the relevant setting in the menu
Tire Load in the DIC, Vehicle
Information Menu 3 114.
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Vehicle care245
Select:■ Light for comfort pressure up to
3 people
■ Eco for Eco pressure up to
3 people
■ Max for full loading
TPMS Sensor Matching
Process
Each TPMS sensor has a unique
identification code. The identification
code must be matched to a new tyre/
wheel position after rotating the tyres
or exchanging the complete wheel set and if one or more TPMS sensors
were replaced. The TPMS sensor
matching process should also be
performed after replacing a spare tyre
with a road tyre containing the TPMS
sensor.
The malfunction light and the warning
message or code should go off at the
next ignition cycle. The sensors are
matched to the tyre/wheel positions,
using a TPMS relearn tool, in the
following order: left side front tyre,
right side front tyre, right side rear tyre and left side rear tyre. The turn signal
light at the current active position is
illuminated until sensor is matched.
Consult your workshop for service or
to purchase a relearn tool. There are
two minutes to match the first tyre/
wheel position, and five minutes
overall to match all four tyre/wheel
positions. If it takes longer, the
matching process stops and must be
restarted.The TPMS sensor matching process
is:
1. Apply the parking brake; on vehicles with automatic
transmission set the selector lever
to P.
2. Turn the ignition on.
3. Use the MENU button on the turn
signal lever to select the Vehicle
Information Menu in the Driver
Information Centre (DIC).
4. Turn the adjuster wheel to scroll to
the tyre pressure menu.
5. Press the SET/CLR button to
begin the sensor matching
process. A message requesting
acceptance of the process should
display.
6. Press the SET/CLR button again
to confirm the selection. The horn sounds twice to signal the
receiver is in relearn mode.
7. Start with the left side front tyre.
8. Place the relearn tool against the tyre sidewall, near the valve stem.Then press the button to activate
the TPMS sensor. A horn chirp
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246Vehicle care
confirms that the sensoridentification code has been
matched to this tyre and wheel
position.
9. Proceed to the right side front tyre,
and repeat the procedure in
Step 8.
10. Proceed to the right side rear tyre,
and repeat the procedure in
Step 8.
11. Proceed to the left side rear tyre, 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 TPMS
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 selected pressure
3 114.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 DIC 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).
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
remains the same.
Tyres age, even if they are not used.
We recommend tyre replacement
every 6 years.