
Engine compartment
223H
Environmental note
When topping up the oil, take care not to
spill any. Oil must not be allowed to escape
into the soil or waterways. You would oth-
erwise be damaging the environment. Coolant
G
Risk of injury
The cooling system is pressurised. There-
fore, only unscrew the cap once the engine
has cooled down. The coolant temperature
gauge must display less than 70 °C. You
could otherwise be scalded by escaping hot
coolant.
Coolant consists of water and antifreeze/cor-
rosion inhibitor. Only check the coolant level
when the vehicle is on a level surface and the
engine has cooled down. Checking the coolant level The expansion tank is located in the engine
compartment on the right-hand side of the
vehicle when viewed in the direction of travel.
1
Cap
2 Expansion tank
3 Marker bar
X Slowly turn cap 1by half a turn anti-clock-
wise to allow excess pressure to escape.
X Turn cap 1further anti-clockwise and
remove it.
There is sufficient coolant in expansion
tank 2if the coolant is level with the
marker bar 3in the filler neck when cold
or approximately 1.5 cm higher when hot. X
Top up the coolant if necessary.
X Replace cap 1and tighten all the way to
the stop.
You will find further information about coolant
in the "Technical data" section
(Y page 360). Windscreen washer system/head-
lamp cleaning system*
The washer fluid reservoir is located in the
engine compartment on the right when
viewed in the direction of travel. The head-
lamp cleaning system is also supplied from
the washer fluid reservoir. 1
Cap
2 Washer fluid reservoir Operation
* optional
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Tyres and wheels
225
lidates the General Operating Permit for the
vehicle.
Notes on selecting, fitting and replacing
tyres
R
Only fit tyres and wheels of the same type
and make.
R Only fit tyres of the correct size onto the
wheels.
R After fitting new tyres, run them in at mod-
erate speeds for the first 100 km as they
only reach their full performance after this
distance.
R Fit new tyres on the front wheels first if
tyres of the same size are required on the
front and rear wheels.
R Replace the tyres after six years at the lat-
est, regardless of wear. This also applies to
the spare wheel*.
R Do not drive with tyres which have too little
tread depth as this significantly reduces
the traction on wet roads (aquaplaning).
! Store tyres that are not being used in a
cool, dry and preferably dark place. Protect
the tyres against oil, grease, petrol and die-
sel. Notes on regularly inspecting wheels
and tyres R
Regularly check the wheels and tyres of
your vehicle for damage (e.g. cuts, punctu-
res, tears, bumps on tyres and deforma-
tion, cracks or severe corrosion on wheels),
at least every 14 days, as well as after driv-
ing off-road or on rough roads. Damaged
wheels could cause a loss of tyre pressure.
R Regularly check the tyre tread depth and
the condition of the tread across the whole
width of the tyre (Y page 226). If neces-
sary, turn the front wheels to full lock in
order to inspect the inner side of the tyre
surface.
R All wheels must have a valve cap to protect
the valve against dirt and moisture.
R Regularly check the pressure of all your
tyres including the spare tyre*, particularly
prior to long trips, and correct the pressure
as necessary (Y page 226).
Notes on driving R
While driving, pay attention to vibrations,
noises and unusual handling characteris-
tics, e.g. pulling to one side. This may indi-
cate that the wheels or tyres are damaged.
If you suspect that a tyre is defective, reduce your speed and stop the vehicle as
soon as possible to check the wheels and
tyres for damage. Hidden tyre damage
could also be causing the unusual handling
characteristics. If you find no signs of dam-
age, have the wheels and tyres examined
at a specialist workshop, for example at a
Mercedes-Benz Service Centre.
R When parking your vehicle, make sure that
the tyres do not get deformed by the kerb
or other obstacles. If it is necessary to drive
over kerbs, speed humps or similar, try to
do so slowly and at an obtuse angle. Oth-
erwise, the tyres, particularly the sidewalls,
could get damaged. Direction of rotation
Direction of rotation Tyres with a specified direction of rotation
have additional benefits, e.g. if there is a risk
of aquaplaning. You will only gain these ben-
efits if the correct direction of rotation is
observed.
An arrow on the sidewall of the tyre indicates
its correct direction of rotation. Operation
* optional
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Care
248
Cleaning the reversing camera*
1
Camera lens
X Use clear water and a soft cloth to clean
camera lens 1.
! Do not clean the camera lens and the area
around the reversing camera with:
R high-pressure cleaning equipment
R a dry cloth and a lot of pressure
R corrosive cleaning products
You could otherwise damage the reversing
camera. Trailer coupling
The ball coupling must be cleaned if it
becomes dirty or corroded.
X Remove any rust using a wire brush.
X Remove dirt with a clean, lint-free cloth or
a brush.
! Do not clean the ball coupling with a high-
pressure cleaner. Do not use solvents. 1
Ball neck head
2 Locking balls
3 Guide pin
4 Guide faces
5 Release lever
6 Protective cap X
Lightly oil or grease positions 1to6 and
the ball coupling recess of the vehicle after
cleaning.
X Treat the lock under protective cap 6with
an acid- and resin-free oil.
X Check that the vehicle's trailer coupling is
working properly.
! Observe the note on care provided by the
trailer manufacturer.
i Maintenance of the ball coupling and
trailer coupling can also be performed by
any Mercedes-Benz Service Centre. H
Environmental note
Dispose of oily and greasy cloths in an envi-
ronmentally-responsible manner. Operation
* optional
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Display
messages 274 Display messages Possible cause/consequence Possible solution
ò Replace air
cleaner element The engine air filter must be replaced. X
Visit a qualified specialist workshop. N Check engine oil
level when next
refuelling The engine oil level has dropped to a crit-
ical level. X
Check the engine oil level (Y page 222) and top
up the engine oil if necessary.
X Have the engine checked for leaks if the engine
oil needs topping up more often than usual. N Engine oil level
Consult workshop The engine oil level has dropped to a crit-
ical level or the measuring system is mal-
functioning.
33 X
Check the engine oil level (Y page 222).
If the engine oil level is OK:
X Visit a qualified specialist workshop.
If the engine oil level is not OK:
X Top up the engine oil.
X If the warning message disappears: consult a
qualified specialist workshop.
X If the warning message does not disappear: do
not drive on. Consult the nearest qualified spe-
cialist workshop. H Tyre pressure Cau-
tion, tyre defect
G
Risk of accident
At least one tyre is rapidly deflating. The
affected wheel is highlighted in the tyre
pressure display of the tyre pressure mon-
itor*. X
Stop the vehicle without making any sudden
steering or braking manoeuvres. Pay attention
to the traffic conditions as you do so.
X Repair or change the tyre (Y page 313).33
Only for certain vehicles. Practical advi
ce
* optional
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