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ProblemPossible causes/consequences andMSolutions
;
The yellow Check
Engine indicator
lamp is lit while
the engine is run-
ning.The exhaust gas aftertreatment is malfunctioning or an emission rel-
evant malfunction has occurred. This malfunction or defect can dam-
age the exhaust gas aftertreatment.
After the first message and under normal operating conditions, you
can drive on for up to approximately 500 mi (800 km). Then a warning
tone sequence sounds and the engine can only be started another 16
times.
XObserve the messages in the display.
XHave the exhaust gas aftertreatment checked immediately at a
qualified specialist workshop.
In some states it is legally prescribed that after the check engine indi- cator lamp lights up you must contact a qualified specialist workshop
immediately. Observe the legal requirements.
% If you turn the key
to position 2in
the ignition lock,
the yellow pre-
glow indicator
lamp remains lit
for approximately
1 minute. Or the
yellow preglow
indicator lamp
lights up for
approximately
1 minute while
the engine is run-
ning.At extremely low temperatures, the engine may not start.
There is a malfunction in the preglow system.
XHave any malfunction rectified at a qualified specialist workshop.
\ The yellow diesel
particle filter indi-
cator lamp is lit
while the engine
is running.The automatic regeneration of the diesel particle filter is not sufficient
or has malfunctioned.
XDrive at an engine speed above 2000 rpm until the diesel particle
filter indicator lamp goes out.
XIf the diesel particle filter indicator lamp does not go out after
approximately 20 minutes: have the malfunction rectified immedi-
ately at a qualified specialist workshop.
ÈThe yellow air fil-
ter indicator lamp
is lit while the
engine is running.The service limit for the air filter has been reached. The air filter is dirty.
XHave the air filter element replaced as soon as possible at a quali-
fied specialist workshop.
Indicator and warning lamps in the instrument cluster201
On-board computer and displays
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If the: indicator lamp in the instrument
cluster goes on, drain fuel filter with water sep-
arator =immediately.
iWe recommend that you have this mainte-
nance work carried out at a qualified special- ist workshop.
XPark the vehicle safely and secure it from roll-
ing away.
XSwitch off the auxiliary heating system .
XSwitch off the engine.
XOpen the hood (Ypage 218).
XPlace a suitable receptacle under drain
hose :.
XTurn the key to position 2in the ignition lock.
XOpen drain plug ;immediately until the
water/fuel mixture flows out of drain hose :.
XScrew in drain plug;as soon as approx-
imately 0.2 qt (0.2 l)of the water/fuel mixture
has been collected.
The electrical fuel pump automatically halts
the flow of the water/fuel mixture after
30 seconds.
XAfter draining, turn the key back to position 0
in the ignition lock.
XDispose of the collected water/fuel mixture
in an environmentally responsible manner,
e.g. at a qualified specialist workshop.
XCheck drain plug ;. The drain plug must be
closed.
When the engine is running and drain hose ;
is open, fuel is lost through drain hose :.
XClose the hood (Ypage 219).
If the : indicator lamp does not go out after
draining:
XDrain the fuel filter again.
XIf the : indicator lamp does not go out
after draining for the second time, have the
cause checked immediately at a qualified spe-
cialist workshop.
Vehicle interior
Air filter for the rear-compartment air
conditioning
!
Regularly check the air filters for visible dirt.
Clean or replace a dirty filter mat. The dirt may
otherwise lead to damage to the air-condi-
tioning system.
Filter magazine, located on the roof in the rear
compartment
An increased amount of sand or dust may collect in the air filter of the rear-compartment air con-
ditioning when you drive on dusty or sandy
roads.
XTo remove the filter mat: carefully pry
cover :out of recesses ;and remove.
XRemove the filter mat from the air duct.
XTo clean the filter mat: wash the dirty filter
mat with clear water.
XLeave the filter mat to dry.
iThe filter mat must not be cleaned or dried in
a machine.
XTo install the filter mat: insert the filter mat
into the air duct.
XReplace and engage cover :.
Maintenance
General notes
HEnvironmental note
Observe measures to protect the environ-
ment when working on the vehicle. You must
observe the legal requirements when dispos-
ing of service products, e.g. engine oil. This
also includes all components, e.g. filters,
which have come into contact with service
products. Any qualified specialist workshop
can provide information about this.
Dispose of empty containers, cleaning cloths
and care products in an environmentally
responsible manner. Comply with the instruc-
tions for use of the care products.
Maintenance225
Maintenance and care
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Regular wheel and tire checks
GWARNING
Damaged tires can cause tire inflation pres-
sure loss. As a result, you could lose control of
your vehicle. There is a risk of accident.
Check the tires regularly for signs of damage
and replace any damaged tires immediately.
Check the wheels and tires of your vehicle for
damage regularly, i.e. at least every two weeks,
as well as after driving off-road or on rough
roads. Damaged wheels can cause a loss of tire
pressure. Pay particular attention to damage
such as:
Rcuts in the tires
Rpunctures
Rtears in the tires
Rbulges on tires
Rdeformation or severe corrosion on wheels
Regularly check the tire tread depth and the
condition of the tread across the whole width of
the tire (
Ypage 248). If necessary, turn the
front wheels to full lock in order to inspect the
inner side of the tire surface.
All wheels must have a valve cap to protect the valve against dirt and moisture. Do not install
anything onto the valve other than the standard
valve cap or other valve caps approved for your vehicle by dealers listed on the inside of the
front cover. Do not install any other valve caps
or systems, e.g. tire pressure monitor systems.
Regularly check the pressure of all the tires,
particularly prior to long trips. Adjust the tire
pressure if ne
cessary (Ypage 250).
The service life of tires depends on various fac-
tors, including the following:
Rdriving style
Rtire pressure
Rmileage
Tire tread
GWARNING
Insufficient tire tread will reduce tire traction.
The tire is no longer able to dissipate water.
This means that on wet road surfaces, the risk
of hydroplaning increases, in particular where
speed is not adapted to suit the driving con-
ditions. There is a risk of accident.
If the tire pressure is too high or too low, tires may exhibit different levels of wear at differ-
ent locations on the tire tread. Thus, you
should regularly check the tread depth and
the condition of the tread across the entire
width of all tires.
Minimum tire tread depth for:
RSummer tires: âin (3 mm)
RM+S tires: ãin (4 mm)
For safety reasons, replace the tires before
the legally prescribed limit for the minimum
tire tread depth is reached.
Bar marking :for tread wear is integrated into
the tire tread.
Tread wear indicators (TWIs) are required by
law. Six indicators are positioned over the tire
tread. They are visible once the tread depth is
approximately áin (1.6 mm). If this is the case,
the tire is so worn that it must be replaced.
Selecting, mounting and renewing
tires
ROnly mount tires and wheels of the same type
and make.
ROnly mount tires of the correct size onto the
wheels.
RBreak in new tires at moderate speeds for the first 65 miles (100 km).
248Operation
Wheels and tires