
Air conditioning
139
X
Press the Ubutton.
The indicator lamp in the |button goes
out. Airflow and air distribution are set to
automatic mode.
or
X Press one of the $or% temperature
buttons.
The indicator lamp in the |button goes
out. The air distribution is directed towards
the windscreen. The air conditioning
switches to manual mode.
or
X Turn thumbwheel 1clockwise or anti-
clockwise (Y page 133).
The indicator lamp in the |button goes
out. The air distribution is directed towards
the windscreen. The air conditioning
switches to manual mode. Demisting the windows
Windows misted up on the inside X
Activate the "cooling with air dehumidifica-
tion" function 19
.
X Activate the automatic air conditioning. 20
X If the windows continue to mist up, activate
the "demisting" function.
Windows misted up on the outside X
Activate the windscreen wipers.
X Turn the air distribution thumbwheel to the
Y ora symbol.
i You should only select this setting until
the windscreen is clear again. Switching the rear window heating
on/off
G
Risk of accident
Clear all windows of ice or snow before set-
ting off. Otherwise, impaired visibility could
endanger you and others.
i The rear window heating has a high cur-
rent draw. You should therefore switch it
off as soon as the window is clear, as it only
switches off automatically after several
minutes.
i If the battery voltage is too low, the rear
window heating may switch off.
X Turn the key to position 2in the ignition
lock.
X To activate, press the 121
/F 22
but-
ton.
The indicator lamp in the 1/Fbut-
ton lights up or goes out.
19 Vehicles with air conditioning*/Thermotronic*.
20 Vehicles with Thermotronic*.
21 Vehicles with an air-conditioning system*/Thermotronic*.
22 Vehicles with Heatmatic. Cont
rols
* optional
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Air conditioning
140 Activating/deactivating air-recircula-
tion mode
You can deactivate the flow of fresh air if
unpleasant odours are entering the vehicle
from outside. The air already inside the vehi-
cle will then be recirculated. G
Risk of accident
Only switch over to air-recirculation mode
briefly at low outside temperatures. Other-
wise, the windows could mist up, thus
impairing visibility and endangering your-
self and others. This may prevent you from
observing the traffic conditions, thereby
causing an accident.
X Turn the key to position 2in the ignition
lock.
X To activate: press theÄbutton.
The indicator lamp in the Äbutton lights
up.
i Air-recirculation mode is activated auto-
matically at high outside temperatures.
When air-recirculation mode is activated
automatically, the indicator lamp in the
Ä button is not lit. Outside air is added after about 30
minutes.
X To deactivate: press theÄbutton.
The indicator lamp in the Äbutton goes
out.
i Air-recirculation mode switches off auto-
matically:
R after approximately five minutes at out-
side temperatures below approximately
7 †
R after approximately 5 minutes if cooling
with air dehumidification 23
is switched
off
R after approximately 30 minutes at out-
side temperatures above approximately
7 †
Convenience opening/closing feature G
Risk of injury
Make sure that nobody can become trap-
ped between the side window and the door
frame as the side windows are opened and
closed. Do not place objects or lean against
the side windows when they are being opened or closed. You or the objects could
be drawn in or become trapped between
the side window and the door frame as the
window moves. If there is a risk of entrap-
ment, press the
Äbutton again. Press
the button for stopping, opening or closing
the side windows in the opposite direction
as appropriate.
Make sure that nobody can become trap-
ped as the panorama louvred sliding sun-
roof *is opened and closed. If there is a risk
of entrapment, press the Äbutton
again. Press the button for stopping, open-
ing or closing the panorama louvred sun-
roof* in the opposite direction as appropri-
ate.
X Convenience closing: press and hold
the Ä button until the side windows and
the panorama louvred sliding sunroof*
have closed.
The indicator lamp in the Äbutton lights
up. Air-recirculation mode is activated.
23 Vehicles with air conditioning*/Thermotronic*. Controls
* optional
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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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Troubleshooting
222 Troubleshooting
Points to remember
G
Risk of accident and injury
The operating safety of your vehicle could be compromised if service work is carried out improperly. You could lose control of the vehicle,
thereby causing an accident. Safety systems may also not be able to protect you or others as intended.
Always have maintenance work carried out at a qualified specialist workshop which has the necessary specialist knowledge and tools to
carry out the work required.
Mercedes-Benz recommends that you use a Mercedes-Benz Service Centre for this purpose.
In particular, work relevant to safety or on safety-related systems must be carried out at a qualified specialist workshop. Warning and indicator lamps in switches and buttons
Problem Possible cause/consequence Suggested solutions
One or all of the indicator lamps
in the seat heating* button are
flashing. The seat heating* has
switched itself off automatically. The on-board voltage is too low,
because too many consumers are
switched on. X
Switch off consumers that are not required, e. g. reading lamp or
interior lighting.
Once the battery is sufficiently charged, the seat ventilation* will
switch back on automatically. The indicator lamp in the
2
button on the air-conditioning */
Ther motronic* control panel
lights up. The cooling system can-
not be switched on. Cooling has been deactivated
due to a malfunction. X
Visit a qualified specialist workshop. Practical advice
* optional
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Trailer coupling*
289Trailer coupling*
Mounting dimensions
G
Risk of accident
Only have a trailer tow hitch retrofitted at a
qualified specialist workshop which has the
necessary specialist knowledge and tools
to carry out the work required. Mercedes-
Benz recommends that you use a
Mercedes-Benz Service Centre for this pur-
pose. In particular, work relevant to safety
or on safety-related systems must be car-
ried out at a qualified specialist workshop.
! If you have a trailer tow hitch retrofitted,
changes to the cooling system may be nec-
essary, depending on the vehicle type. If you have a trailer tow hitch retrofitted,
observe the anchorage points on the chas-
sis frame. Anchorage points for the trailer coupling
1 Anchorage points
2 Overhang dimension
3 Rear axle centre line For trailer tow hitches fitted at the factory, the
overhang dimension is 749 mm. Technical data
* optional
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Service products and capacities
297Coolant
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It performs the
following tasks:
R anti-corrosion protection
R antifreeze protection
R raising the boiling point
i When the vehicle is first delivered, it is
topped up with a coolant that will ensure
adequate antifreeze and corrosion protec-
tion.
! Only top up with coolant that has been
premixed with the desired antifreeze pro-
tection. Otherwise, you could damage the
engine.
Further information on coolants and on fill-
ing can be found in the Mercedes-Benz Specifications for Service Products, sheet
310.1, or at any Mercedes-Benz Service
Centre.
! Always use a suitable coolant mixture,
even in countries where high temperatures
prevail.
Otherwise, the cooling system will not be
sufficiently protected from corrosion, and
the boiling point will be too low.
If antifreeze/corrosion inhibitor is present in
the correct concentration, the boiling point of
the coolant will be around 130 °C.
The antifreeze/corrosion inhibitor concentra-
tion in the cooling system should: R
be at least 50%. This will protect the cooling
system against freezing down to around –
37 °C.
R not exceed 55% concentration (antifreeze
protection down to –45 °C); otherwise,
heat will not be effectively dissipated.
If the vehicle has lost coolant, top it up with
equal amounts of water and antifreeze/cor-
rosion inhibitor. Mercedes-Benz recom-
mends an antifreeze/corrosion inhibitor
which has been approved for Mercedes-Benz.
! The cooling system contains a supply
which must be renewed after 15 years, or
after 250, 000 km at the latest.
The warranty is only valid if you top up with
an antifreeze/corrosion inhibitor which
has been approved by Mercedes-Benz and
the recommended mixture ratio is
observed. Technical data
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Service products and capacities
298
Capacities The following values indicate the total cooling system capacities.
B 150
Manual trans- mission B 150
BlueEFFICIENCY B 150
AUTOTRONIC* B 170
Manual trans- mission B 170
BlueEFFICIENCY B 170
AUTOTRONIC* Coolant
6.3 l 6.3 l 6.5 l 6.3 l 6.3 l 6.6 l
Amount of antifreeze/corrosion inhibitor required for antifreeze protection
Down to
–37 †(approx.
50%)
3.2 l 3.2 l 3.25 l 3.2 l 3.2 l 3.0 l
Down to
–45 †(approx.
55%)
3.5 l 3.5 l 3.6 l 3.5 l 3.5 l 3.65 l
B 200 B 200
TURBO B 180 CDI B 200 CDI
Coolant
6.6 l 8.5 l 8.0 l 9.7 lTechnical data
* optional
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