light MERCEDES-BENZ B-CLASS HATCHBACK 2008 Owners Manual

Engine compartment
171Engine compartment
Bonnet
G
Risk of accident
Do not pull the release lever while the vehi-
cle is in motion. If you do so, the bonnet
may open up and block your view.
Opening G
Risk of injury
There is a risk of injury if the bonnet is open,
even if the engine is not running.
Some engine components can become
very hot.
To avoid the risk of burns, only touch those
components described in the Owner’s Man-
ual and observe the relevant safety notes. G
Risk of injury
The radiator fan between the radiator and
the engine can start automatically, even if
the key has been removed from the ignition
lock. For this reason, you must not reach
into the fan rotation area. Otherwise, you
could be injured. Vehicles with a petrol engine:
The electronic ignition system uses high
voltage. For this reason, you must never
touch components of the ignition system
(ignition coil, ignition cable, spark plug con-
nector or test socket) when:
R
the engine is running.
R the engine is being started.
R the ignition is switched on and the engine
is being cranked by hand.
Vehicles with a diesel engine:
The electronic injection control uses high
voltage. Therefore, never touch fuel injec-
tion system components when:
R the engine is running.
R the engine is being started.
R the ignition is switched on.
X Make sure that the windscreen wipers are
switched off. G
Risk of injury
The windscreen wipers and wiper linkage
could be set in motion.
When the bonnet is open, you or others
could be injured by the wiper rods. Make sure that the windscreen wipers are
switched off and that the key has been
pulled out of the ignition lock before open-
ing the bonnet.
The bonnet release lever is located in the
driver's footwell. 1
Bonnet release lever
X Pull bonnet release lever 1.
The bonnet is released.
! Make sure that the windscreen wipers
are not folded away from the windscreen.
Otherwise, you could damage the wind-
screen wipers or the bonnet. Operation
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Engine compartment
172
The handle for opening the bonnet is located
above the radiator grille. 2
Bonnet catch handle
X Pull handle 2of the bonnet catch out-
wards from the radiator grille and lift the
bonnet from underneath by the radiator
grille. 3
Recess
4 Support strut
5 Bracket
X Pull support strut 4out of bracket 5.
X Swing support strut 4upwards and insert
it into yellow recess 3.
Closing G
Risk of injury
Make sure that nobody can become trap-
ped as you close the bonnet.
X Raise the bonnet slightly and remove sup-
port strut 4from yellow recess 3.
X Swing support strut 4down and press it
into bracket 5until it engages. X
Lower the bonnet and let it fall from a
height of approximately 20 cm.
X Check that the bonnet has engaged prop-
erly. Engine oil
Depending on driving style, the vehicle con-
sumes a maximum of 0.8 l oil per 1,000 km.
The oil consumption may be higher than this
when the vehicle is new or if you frequently
drive at high engine speeds. You can only
estimate the oil consumption after you have
driven a considerable distance.
For further information on engine oil see
(Y page 295).
Checking the engine oil level To do so:
R
the vehicle should be parked on level
ground
R the engine should be switched off for at
least five minutes if the engine was at nor-
mal operating temperature.
R the engine should be switched off for at
least 30 minutes if the engine was not at Operation
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Engine compartment
173
operating temperature (i.e. if you only star-
ted the engine briefly)
Using the on-board computer*
i Only possible on vehicles with a diesel
engine. A dipstick is used to check petrol
engines (Y page 174).
X Make sure that the key is in position
2(Y page 62) in the ignition lock.
X Press the jork button to select the
following message: The measurement takes a few seconds. You
will see one of the following messages in the
display: R
Engine oil level OK
R Add 1.0 litre to reach maximum oil
level
R Add 1.5 litres to reach maximum oil
level
R Add 2.0 litres to reach maximum oil
level
X Top up the oil if necessary ( Ypage 174).
Other messages in the multi-function dis-
play
If the engine is at normal operating tempera-
ture and there is too much oil, you will see the
following message:
Eng. oil level
Reduce oil level
X Have excess oil siphoned off.
! There is a risk of damage to the engine or
the catalytic converter if there is excess oil
in the engine.
If the Switch ignition on to check
engine oil level message appears:
X Turn the key to position 2(Y page 62) in
the ignition lock.
You will see the following message if you did
not observe the required waiting period: Observe waiting period
X
Repeat the measurement after about five
minutes if the engine is at normal operating
temperature.
X Repeat the measurement after about
30 minutes if the engine is not at normal
operating temperature (if the engine was
only started briefly).
The following message appears if the engine
is running:
Engine oil level Not when engine on
X Switch off the engine and wait for five
minutes if the engine is at normal operating
temperature, or for about 30 minutes if the
engine is not at normal operating temper-
ature (if the engine was only started
briefly), before measuring.
i If you wish to cancel the measurement,
press the korj button on the multi-
function steering wheel. Operation
* optional
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Engine compartment
174
Using the oil dipstick
Example: vehicles with a petrol engine
1
Oil dipstick
2 Maximum mark
3 Minimum mark Example: vehicles with a turbo/diesel engine
1
Oil dipstick
2 Maximum mark
3 Minimum mark
X Pull oil dipstick 1out of the oil dipstick
tube.
X Wipe off oil dipstick 1.
X Insert oil dipstick 1into the oil dipstick
tube to the stop, and take it out again.
The oil level is correct if the level is between
minimum mark 3and maximum mark
2.
X Top up the oil if necessary. Topping up the engine oil Example: vehicles with a petrol/diesel engine
1
Cap
X Unscrew cap 1and remove it.
X Top up with the required amount of oil
(Y page 295).
i The difference in quantity between the
minimum mark and the maximum mark is
approximately 1.5 litres.
! Do not add too much oil. If too much oil
is added and the oil level is above the max-
imum mark on the dipstick, the engine or
catalytic converter could be damaged.
Have excess oil siphoned off.
X Screw cap 1onto the filler neck. Operation
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Engine compartment
175H
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.
For further information on engine oil
(Y page 295). 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 coolant expansion tank is located in the
engine compartment on the right when
viewed in the direction of travel.
1
Cap
2 Coolant expansion tank
3 Marker bar
X Slowly turn cap 1half 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 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.
For further information on coolant see
(Y page 297) . Windscreen washer system/head-
lamp cleaning system*
The washer fluid reservoir is located in the
engine compartment on the left-hand side of
the vehicle when viewed in the direction of
travel. The headlamp cleaning system is also
supplied from the washer fluid reservoir. 1
Cap
X Add windscreen washer concentrate to the
washer fluid all year round. Operation
* optional
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Tyres and wheels
176 G
Risk of fire
Washer fluid concentrate is highly flamma-
ble. Fire, naked flames and smoking are
prohibited when washer fluid concentrate
is being handled.
X At temperatures above freezing:
fill the washer fluid reservoir with a mix of
water and windscreen washer concentrate
(Y page 175).
X At temperatures below freezing:
fill the washer fluid reservoir with a mix of
water, antifreeze additive and windscreen
washer concentrate ( Ypage 175). Adapt
the mixing ratio to the outside tempera-
tures.
X Mix the windscreen washer fluid in a con-
tainer beforehand.
! Only use windscreen washer fluid which
is suitable for plastic lamp lenses. Unsuit-
able windscreen washer fluid could dam-
age the plastic lamp lenses of the head-
lamps.
X To open: pull cap1upwards by the tab.
X To close: press cap 1onto the filler neck
until it clicks into place. Tyres and wheels
Points to remember
! For safety reasons, Mercedes-Benz rec-
ommends that you only use tyres and
wheels which have been approved by
Mercedes-Benz specifically for your vehi-
cle. These tyres have been specially adap-
ted for use with the control systems, such
as ABS or ESP ®
, and are marked as follows:
R MO = Mercedes-Benz Original
R MOE = Mercedes-Benz Original Extended
(with run-flat characteristics)*
*Mercedes-Benz Original Extended tyres
should only be used on wheels that have
been specifically approved by Mercedes-
Benz.
If you use other tyres and wheels,
Mercedes-Benz cannot accept any respon-
sibility for damage that may result from
this. Further information about tyres,
wheels and approved combinations can be
obtained from any Mercedes-Benz Service
Centre.
If you use tyres other than those tested and
recommended for Mercedes-Benz vehi-
cles, characteristics such as handling, vehi-
cle noise emissions and fuel consumption may be adversely affected. In addition, the
wheels may come into contact with the
body or axle components when heavily loa-
ded or when driving with snow chains. This
could result in damage to the tyres or the
vehicle.
! Retreaded tyres are neither tested nor
recommended by Mercedes-Benz, since
previous damage cannot always be detec-
ted on retreaded tyres. As a result,
Mercedes-Benz cannot guarantee vehicle
safety if retreaded tyres are fitted. Do not
fit used tyres if you have no information
about their previous usage. G
Risk of accident
If wheels or tyres other than those which
have been tested are fitted:
R the brakes or chassis components could
be damaged.
R wheel and tyre clearances can no longer
be guaranteed.
This could cause an accident.
Modification work on the brake system and
wheels is not permitted, nor is the use of
spacer plates or brake dust shields. This inva- Operation
* optional
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Tyres and wheels
177
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, bulges on tyres and deformation,
cracks or severe corrosion on wheels), at
least every 14 days, as well as after driving
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 178). 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 178).
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
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.
i You may fit a spare tyre* against the
direction of rotation. Operation
* optional
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Tyres and wheels
178 MOExtended run-flat system*
The MOExtended run-flat system allows you
to continue driving the vehicle even when one
or more tyres lose all air pressure.
The MOExtended run-flat system may only be
used in combination with the tyre pressure
loss warning system and only on wheels spe-
cifically tested and approved by Mercedes-
Benz.
i Vehicles with MOExtended run-flat sys-
tem are not equipped with the TIREFIT
kit* 24
.
Therefore, it is recommended that you
equip your vehicle additionally with the
TIREFIT kit* when fitting tyres that do not
feature run-flat properties, e.g. winter
tyres.
i A TIREFIT kit* is available from any quali-
fied specialist workshop, e.g. a Mercedes-
Benz Service Centre.
You will find notes on driving with a flat tyre
in the "Practical advice" section
(Y page 262). Tyre tread
G
Risk of accident
Bear in mind that:
R tyre grip decreases rapidly on wet roads
when the tread depth is less than 3 mm.
Thus, you should replace tyres that have
insufficient tread.
R winter tyres should be replaced when the
tread depth is 4 mm or less as they will
no longer provide adequate grip.
R the tread on a tyre may not wear evenly.
Thus, you should regularly check the
tread depth and the condition of the
tread across the entire width of all tyres.
If necessary, turn the steering wheel so
that you can see the tyre tread more eas-
ily.
Otherwise, you could lose control of the
vehicle and cause an accident due to the
reduced grip of the tyres on the road. Tyre pressures
i You will find a table of tyre pressures for
various operating conditions on the inside
of your vehicle's fuel filler flap.
The valid value for the spare wheel* is sta-
ted on the spare wheel and in the technical
data section. G
Risk of accident
Tyre pressure that is either too high or too
low has a negative effect on the vehicle’s
driving safety, which could lead you to
cause an accident. Therefore, you should
regularly check the pressure of all the tyres
(including the spare tyre*), particularly
prior to long trips, and correct the pressure
as necessary.
To test tyre pressure, use a suitable pressure
gauge. The outer appearance of a tyre does
not permit any reliable conclusion about the
tyre pressure. G
Risk of accident
Should the tyre pressure drop repeatedly:
24 Only for certain countries. Operation
* optional
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Tyres and wheels
179R
check the tyre for foreign bodies.
R check whether the wheel is losing air or
the valve is leaking.
Tyre pressure that is too low has a negative
effect on the vehicle's active safety, which
could lead to your causing an accident.
Tyre pressure changes by approximately
0.1 bar for every 10 °C change in ambient
temperature.
If you measure the tyre pressure in enclosed
spaces where the temperature differs from
the outside temperature, you will have to cor-
rect the measured value accordingly.
When the vehicle is driven, the tyre tempera-
ture, and with it the tyre pressure, will
increase depending on the road speed and
the load on the tyres.
Therefore, you should only correct tyre pres-
sures when the tyres are cold.
The pressure of warm tyres should only be
corrected if it is too low for the current oper-
ating conditions. Driving with tyre pressure that is too high or
too low can:
R
shorten the service life of the tyres
R increase the likelihood of tyre damage
R have a negative effect on handling charac-
teristics (e.g. by causing aquaplaning)
i The tyre pressure values given for low
loads are minimum values which offer you
good ride comfort characteristics.
However, you can also use the values given
for higher loads. These are permissible and
will not adversely affect the running of the
vehicle. H
Environmental note
Check the tyre pressure regularly, at least
every 14 days. Tyre pressure loss warning system
While the vehicle is in motion, the tyre pres-
sure loss warning system monitors the set
tyre pressure using the rotational speed of
the wheels. This enables the system to detect
significant pressure loss in a tyre. If the speed
of rotation of a wheel changes as a result of
a loss of pressure, a corresponding warning
message will appear in the multi-function dis-
play. G
Risk of accident
The tyre pressure loss warning system does
not warn you of an incorrectly set tyre pres-
sure. The table on the inside of the fuel filler
flap will help you decide whether the tyre
pressures should be corrected.
The tyre pressure loss warning system does
not replace the need to regularly check
your vehicle's tyre pressures, since an even
loss of pressure on several tyres at the
same time cannot be detected by the tyre
pressure loss warning system.
The tyre pressure loss warning system is
not able to warn you of a sudden loss of
pressure, e.g. if the tyre is penetrated by a
foreign object.
In the event of a sudden loss of pressure,
bring the vehicle to a halt by braking care- Operation
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Tyres and wheels
180 fully. Do not make any sudden steering
movements when doing so.
The function of the tyre pressure loss warning
system is limited or delayed if:
R snow chains are fitted to your vehicle's
tyres.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style (cor-
nering at high speeds or driving with high
rates of acceleration).
R you are towing a very heavy or large trailer.
R you are driving with a heavy load (in the
vehicle or on the roof).
Restarting the tyre pressure loss warn-
ing system Restart the tyre pressure loss warning system
if you have:
R changed the tyre pressure
R changed the wheels or tyres
R fitted new wheels or tyres
X Before restarting, consult the table of tyre
pressures on the inside of the fuel filler flap
to ensure that the tyre pressure in all four tyres is set correctly for the operating con-
ditions concerned.
X Also observe the notes in the section on
tyre pressures (Y page 178). G
Risk of accident
The tyre pressure loss warning system can
only give reliable warnings if you have set
the correct tyre pressure.
If an incorrect tyre pressure is set, these
incorrect values will be monitored.
A tyre with insufficient pressure results in
vehicle instability when driving, thus
increasing the risk of an accident.
X Make sure that the key is in position
2(Y page 62) in the ignition lock.
You will see the following message on the
standard screen of the multi-function dis-
play (Y page 99)
X Press korj to select the tyre pres-
sure function:
Run Flat Indicator active
Menu: R-Button
X Press the reset button on the left of the
instrument cluster.
The following message appears in the
multi-function display: Restart Run Flat Indicat.? Yes Can-
cel
If you wish to confirm the restart:
X Press the æbutton.
The following message appears in the
multi-function display:
Run Flat Indicator restarted
After a teach-in period, the tyre pressure
loss warning system will monitor the set
tyre pressures of all four tyres.
If you wish to cancel the restart:
X Press the çbutton.
or
X Wait until the message
Restart Run Flat Indicator?
Yes Cancel disappears.
The tyre pressure values stored at the last
restart will continue to be monitored. Operation
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