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Operation
CAUTION
Follow the instructions given in the manual. Roof load
The maximum permissible roof load (includ-
ing the support system) of
75 k
g and the total
authorised weight of the vehicle must not be
exceeded.
It will not be possible to carry the full maxi-
mum load if the roof carrier you are using is
rated for a load which is less than this figure.
In this case, you can only load the roof carrier
to the maximum load permitted in your instal-
lation manual. Air conditioning
Heating and air conditioning Gener al not
es The power of the heating depends on the
temper
at
ure of the coolant. Therefore, maxi-
mum power is only obtained when the engine
has reached operating temperature.
The temperature and humidity of the air in-
side the vehicle decrease when the cooling
system is turned on. This therefore increases
the comfort of all vehicle occupants when
outside temperatures and humidity are high. It
also helps prevent the windows from misting
over during cold periods of the year.
The air recirculation system can be switched
on temporarily to increase the cooling effect.
Keep the air intake slots in front of the wind-
screen clear of ice, snow or leaves to ensure
unimpaired heating and cooling.
When the air conditioning is on, condensa-
tion can drip from the evaporator in the air
cooling system and form a pool underneath
the vehicle. This is normal and does not indi-
cate a leak! WARNING
Page 198 of 300
Driving
Driving
St ar
t and driving
St
arting and stopping the
engine
Introduction Read the additional information carefully
Page 206 of 300
Driving
engage the handbrake firmly and the move
the sel ect
or l
ever to the parking position. This
reduces the load on the lock mechanism
while making it easier to move the selector
lever from position P.
If, while the vehicle is moving, the selector lev-
er is accidentally moved to position N, re-
lease the accelerator and wait for the engine
to idle before moving it back into position. WARNING
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Start and driving
applied if the brake is not pressed and the se-
l ect
or l
ever is moved to position N for more
than 2 seconds.
The selector lever only locks when the is vehi-
cle stationary or driving at a speed lower
than 5 km/h (3 mph). At a higher speed, it au-
tomatically disconnects in the N position.
Interlock button
The interlock button on the selector lever
knob prevents the driver from inadvertently
engaging a gear. Press the button to unlock
the selector lever.
Safety interlock for ignition key 1)
After switching the ignition off, the ignition key
can be removed only when the selector lever
is in position P. If the key is not in the ignition,
the selector lever is locked in position P.
Driving programmes Your vehicle is equipped with an electronical-
ly-contr
oll
ed aut
omatic gearbox. Shifting up
or down depends on the programme selec-
ted.
For a calm driving style, the gearbox uses
the most economic programme. The gearbox shifts up as quickly as possible and shifts
down as lat
e as possible, thus increasing driv-
ing economy.
With a sporty driving style, characterised by
sudden acceleration, heavy acceleration,
speeds that often increase and decrease and
maximum speed, the gearbox adapts to this
driving style when the accelerator is pressed
down fully (kick-down) by shifting down as
quickly as possible and can even shift down
by several gears at once.
Selecting the best driving programmes is an
endless job. Regardless of this, the driver can
also make the gearbox switch to a more dy-
namic gear shift programme by pressing the
accelerator quickly. This makes the automat-
ic gearbox shift down into a lower gear than
the one that would normally apply to the cur-
rent speed, allowing for more rapid accelera-
tion (e.g. to overtake another vehicle) without
having to press the accelerator until the kick-
down position. On shifting up in a corre-
sponding driving style, the gearbox returns to
the original programme.
When driving along mountain roads, the
gearbox adapts to the gradients. This avoids
having to frequently change gears when driv-
ing uphill. In Tiptronic mode, it is possible to
shift down manually when driving downhill to
use the braking effect of the engine. Emergency program A back-up programme exists in case of faults.
In the ev
ent of a f
ault in the gearbox electron-
ics, it will continue to work in one of the corre-
sponding back-up programmes. All segments
of the screen are lit up or switched off.
The fault can be seen as follows:
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Start and driving
Steering Inf ormation r
el
ating to vehicle
steering Electro-mechanical power steering assists
the driver when st
eering.
El
ectro-mechanical power steering adapts
electronically to the speed of the car, torque
and turning angle.
If the power steering should fail at any time or
the engine is switched off (for instance when
being towed), the car can still be steered, as
long as the key remains in the ignition. How-
ever, more effort than normal will be required
to turn the steering wheel. WARNING
If the power steering does not work, you
will need much more str ength t
o turn the
wheel. This has a considerable effect on
vehicle safety.
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Driving
pollutant emissions are also especially high
during this initial w arm-up phase
. It is ther
e-
fore best to drive off immediately after start-
ing the engine. Avoid running the engine at
high speed.
Periodic maintenance
Periodic maintenance work guarantees that,
before beginning a journey, you will not con-
sume more than the required amount of fuel.
A well-serviced engine gives you the benefit
of improved fuel efficiency as well as maxi-
mum reliability and an enhanced resale val-
ue.
A badly serviced engine can consume up to
10% more fuel than necessary.
Avoid short journeys
To reduce the consumption and emission of
polluting exhaust gases, the engine and the
exhaust gas filtration systems should reach
the optimum operating temperature.
With the engine cold, fuel consumption is pro-
portionally higher. The engine does not warm
up and fuel consumption does not normalise
until having driven approximately four kilome-
tres (2.5 miles). This is why we recommend
avoiding short trips whenever possible.
Maintain the correct tyre pressures
Bear in mind that keeping the tyres at an ade-
quate pressure saves fuel. If the tyre pressure is just one bar (14.5 psi/100 kPa) too low, fuel
consumption can increase by as much as 5%.
Due to the gr
eater rolling resistance, under-
inflation also increases tyre wear wear and
impairs handling.
The tyre pressures should always be checked
when the tyres are cold.
Do not use winter tyres all year round as
they increase fuel consumption by up to 10%.
Avoid unnecessary weight
Given that every kilo of extra weight will in-
crease the fuel consumption, it is advisable to
always check the luggage compartment to
make sure that no unnecessary loads are be-
ing transported.
A roof rack is often left in place for the sake of
convenience, even when it is no longer nee-
ded. At a speed of 100 km/h (62 mph) and
120 km/h (75 mph) your vehicle will use about
12% more fuel as a result of the extra wind re-
sistance caused by the roof rack even when it
is not in use.
Save electricity
The engine activates the alternator, which
produces electricity. With the need for elec-
tricity, fuel consumption also increases. Be-
cause of this, always turn off electrical devi-
ces when you do not need them. Examples of
devices that use a lot of electricity are: the fan at high speeds, the rear window heating
and the seat heaters*. Note
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Start and driving
Engine management and
emission contr ol syst
em
Intr
oduction WARNING
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Driving
For the sake of the environment
Even when the emission control system is
working perf ectly, ther
e may be a smell of
sulphur from the exhaust gas under some
conditions. This depends on the sulphur
content of the fuel used. Quite often the
problem can be solved by changing to an-
other brand of fuel. Particulate filter
Applies to v
ehicl
es with diesel engine
The diesel engine particulate filter eliminates
most of the soot from the exhaust gas system.
Under normal driving conditions, the filter
cleans itself. The particulate filter is cleaned
automatically without need for indication by
the warning lamp . This may be noticed because the engine idle speed increases and
an odour may be detected.
If automatic filter purification cannot be car-
ried out (because only short trips are taken,
for example), soot will accumulate on the fil-
ter and the particulate filter warning lamp will
switch on.
Facilitate the automatic filter cleaning proc-
ess by driving in the following manner: