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Climate control159Maintenance
Air intake
The air intake in front of the
windscreen in the engine
compartment must be kept clear to
allow air intake. Remove any leaves,
dirt or snow.
Pollen filter
The pollen filter cleans dust, soot,
pollen and spores from the air
entering the vehicle through the air
intake.
Air conditioning regular
operation In order to ensure continuously
efficient performance, cooling must
be operated for a few minutes once a
month, irrespective of the weather
and time of year. Operation with
cooling is not possible when the
outside temperature is too low.
Service
For optimal cooling performance, it is recommended to annually check the
climate control system, starting
three years after initial vehicle
registration, including:
■ Functionality and pressure test■ Heating functionality
■ Leakage check
■ Check of drive belts
■ Cleaning of condenser and evaporator drainage
■ Performance check
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Driving and operating217Trailer hitch
General information
Only use towing equipment that has
been approved for your vehicle.
Entrust retrofitting of towing
equipment to a workshop. It may be
necessary to make changes that
affect the cooling system, heat
shields or other equipment.
The bulb outage detection function for trailer brake light cannot detect a
partial bulb outage, e.g. in case of 4 x
5 Watt bulbs, the function only detects
lamp outage when only a single
5 Watt lamp remains or none remain.
Fitting of towing equipment could
cover the opening of the towing eye.
If this is the case use the coupling ball bar for towing. Always keep the
coupling ball bar in the vehicle.Driving characteristics and
towing tips Before attaching a trailer, lubricate
the coupling ball. However, do not do
so if a stabiliser, which acts on the
coupling ball, is being used to reduce snaking movements.
For trailers with low driving stability
and caravan trailers with a permitted
gross vehicle weight of more than
1300 kg (Sports tourer: 1200 kg) the use of a stabiliser is strongly
recommended when driving above
80 km/h.
If the trailer starts snaking, drive more
slowly, do not attempt to correct the
steering and brake sharply if
necessary.
When driving downhill, drive in the
same gear as if driving uphill and
drive at a similar speed.
Adjust tyre pressure to the value
specified for full load 3 309.Trailer towing
Trailer loads
The permissible trailer loads are
vehicle and engine-dependent
maximum values which must not be exceeded. The actual trailer load is
the difference between the actual
gross weight of the trailer and the
actual coupling socket load with the
trailer coupled.
The permissible trailer loads are
specified in the vehicle documents. In general, they are valid for gradients
up to max. 12 %.
The permitted trailer load applies up to the specified incline and up to an
altitude of 1000 metres above sea
level. Since engine power decreases
as altitude increases due to the air
becoming thinner, therefore reducing
climbing ability, the permissible gross
train weight also decreases by 10 %
for every 1000 metres of additional
altitude. The gross train weight does
not have to be reduced when driving
on roads with slight inclines (less than
8 %, e.g. motorways).
Page 225 of 343

Vehicle care223
■ Open the bonnet, close all doorsand lock the vehicle.
■ Disconnect the clamp from the negative terminal of the vehicle
battery. Beware that all systems are
not functional, e.g. anti-theft alarm
system.
Putting back into operation
When the vehicle is to be put back into
operation:
■ Connect the clamp to the negative terminal of the vehicle battery.
Activate the electronics of the
power windows.
■ Check tyre pressure.
■ Fill up the washer fluid reservoir.
■ Check the engine oil level.
■ Check the coolant level.
■ Fit the number plate if necessary.
End-of-life vehicle
recovery
Information on end-of-life vehicle
recovery centres and the recycling of
end-of-life vehicles is available on ourwebsite, where legally required. Only
entrust this work to an authorised
recycling centre.
Gas vehicles must be recycled by a
service centre authorised for gas
vehicles.Vehicle checks
Performing work9 Warning
Only perform engine compartment
checks when the ignition is off.
The cooling fan may start
operating even if the ignition is off.
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226Vehicle care
Coolant levelCaution
Too low a coolant level can causeengine damage.
If the cooling system is cold, the
coolant level should be above the
filling line mark. Top up if the level is
low.
9 Warning
Allow the engine to cool before
opening the cap. Carefully open
the cap, relieving the pressure
slowly.
To top up use a 1:1 mixture of
released coolant concentrate mixed
with clean tap water. If no coolant
concentrate is available, use clean
tap water. Install the cap tightly. Have
the coolant concentration checked
and have the cause of the coolant
loss remedied by a workshop.
Power steering fluid
Caution
Extremely small amounts of
contamination can cause steering
system damage and cause it to not work properly. Do not allow
contaminates to contact the fluid
side of the reservoir cap/dipstick or
from entering the reservoir.
Power steering fluid level normally
does not have to be checked. If an
unusual noise sounds during steering or the power steering reacts
unusually, seek the assistance of a workshop.
Page 253 of 343
Vehicle care251Engine compartment fuse
box
The fuse box is in the front left of the
engine compartment.
Disengage the cover and fold it
upwards until it stops. Remove the
cover vertically upwards.
No.Circuit1Engine control module2Lambda sensor3Fuel injection, ignition system4Fuel injection, ignition system5–6Mirror heating, anti-theft alarm
system7Fan control, engine control
module, transmission control
module8Lambda sensor, engine cooling9Rear window sensor10Vehicle battery sensor11Trunk release12Adaptive forward lighting, auto‐
matic light control13ABS14Rear window wiper