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Driving
The paddle levers are activated when the selector lever is in position D or S,
or the position for the manual shift programme (tiptronic).
The manual shift programme can, of course, still be operated using the gear
lever in the centre console.
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Intelligent technology
WARNING
The ESC is not able to overcome the physical limits of adhesion. Even
with ESC, you should always adjust your speed to suit the road and traffic
conditions. Please bear this in mind, especially on wet or slippery road
surfaces. Do not let the extra safety features tempt you into taking any
risks when driving. Failure to do so could result in an accident.
Anti-lock brake system (ABS)
ABS prevents the wheels from locking up under braking.
The anti-lock brake system (ABS) is an important part of the vehicle's active
safety system. However, the ABS will not necessarily guarantee shorter
stopping distances in all conditions. For instance, on loose gravel or fresh
snow on top of an icy surface (conditions which anyway require extreme
care and reduced speed), the stopping distance with ABS may even be
slightly longer.
How the ABS works
The system runs an automatic self-check when the vehicle reaches a road
speed of about 6 km/h. This may be accompanied by a noise from the ABS
pump.
When one of the wheels is turning very slowly in relation to the road speed
and is close to locking up, the system will reduce the brake pressure on that
wheel. The driver is made aware of this adjustment process by a vibration of
the brake pedal and an audible noise. This is a deliberate warning to the
driver that one or more of the wheels is tending to lock up and the ABS con-
trol function has intervened. In this situation it is important to keep the
brake pedal fully depressed so the ABS can regulate the brake application,
but do not “pump” the brake pedal.
WARNING
The grip provided by ABS is still subject to the physical limits of adhe-
sion. Always bear this in mind, especially on wet or slippery roads. If you
notice that the ABS is working (to counteract locked wheels under brak-
ing), you should reduce speed immediately to suit the road and traffic
conditions. Do not let the extra safety features tempt you into taking any
risks when driving. Failure to do so could result in an accident.
Note
If a malfunction should occur in the ABS, this is indicated by a warning lamp
⇒ page 70.
Brake assist system
The brake assist system helps the driver to achieve optimum
braking effect.
The brake assist system helps to increase braking power and thus to ach-
ieve a shorter stopping distance. If the driver presses the brake pedal very
quickly, the brake assist system automatically boosts the braking force to
the maximum level, up to the point where the anti-lock brake function (ABS)
intervenes to stop the wheels from locking. You should then keep the brake
pedal pressed until the vehicle has braked to the required speed. The brake
assist system switches itself off as soon as you release the brake pedal.
The brake assist system will not be operative if there is a malfunction in the
ABS or the ESC.
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The traction control system (ASR) helps the car to start moving, accelerate
and climb a gradient in slippery conditions where this may otherwise be dif-
ficult or even impossible.
How it works
The ASR works automatically, i.e. without the driver's involvement. With the
aid of the ABS sensors , the ASR monitors the speed of the driven wheels
⇒ page 197. If the wheels start to spin, the engine speed is reduced auto-
matically to match the amount of grip available. The system is active across
the entire speed range.
The ASR works in conjunction with the ABS. If a failure occurs in the ABS,
the ASR will also stop working.
In general, the ASR should be left switched on at all times. It should only be
switched off manually in particular circumstances where a certain amount of
wheel slip may be desirable. Examples:
● when driving with snow chains
● when driving in deep snow or on loose surfaces
● when rocking the vehicle backwards and forwards to free it.
The ASR should be switched on again afterwards as soon as possible.
Note
To ensure that the ASR works properly, all four wheels must be fitted with
identical tyres. The difference in size of the wheels may lead to an unde-
sired reduction in engine power. Also see ⇒ page 257.Brakes
General notes
New brake pads
New brake pads do not provide optimal performance during the first 200 km
(250 miles); first they must be “run in”. However, the reduced braking ca-
pacity may be compensated by pressing on the brake pedal a little harder.
Avoid overloading the brakes during run-in.
Wear
The rate of wear on the brake pads depends a great deal on how you drive
and the conditions in which the vehicle is operated. Negative factors are, for
instance, city traffic, frequent short trips or hard driving with abrupt starts
and stops.
Wet roads or road salt
In certain conditions, such as in heavy rain, or after washing the vehicle or
driving through water, the full braking effect can be delayed by moisture (or
in winter by ice) on the discs and brake pads. In this case the brakes should
be dried by pressing the brake pedal several times.
The effectiveness of the brakes can also be temporarily reduced if the vehi-
cle is driven for some distance without using the brakes when there is a lot
of salt on the road in winter. In this case, the layer of salt on the brake discs
and pads has to wear off before braking.
Corrosion
There may be a tendency for corrosion to form on the discs and dirt to build
up on the brake pads if the vehicle is used infrequently or the brakes are
not used very often.
If the brakes are not used frequently, or if rust has formed on the disks, it is
advisable to clean off the pads and disks by braking firmly a few times at a
moderately high speed ⇒
.
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CAUTION
When the engine is running, do not turn the steering wheel to its limit for
more than 15 seconds. Otherwise, there is a risk of damaging the power
steering.
Note
● If the power steering should fail at any time or the engine is switched off
(for instance when being towed), the vehicle can still be steered. However,
more effort will be required to turn the steering wheel.
● If the system is leaking or malfunctioning, please take the vehicle to a
specialised workshop as soon as possible.
● The power steering system requires a special hydraulic fluid. The fluid
reservoir is located at the front of the engine compartment on the left
⇒ page 306. The correct fluid level in the reservoir is important for the pow-
er steering to function properly. The hydraulic fluid level is checked at the
Inspection Service.
Servotronic*
The servotronic system electronically adjusts the power as-
sisted steering.
In vehicles equipped with servotronic power steering the degree of power
assistance ⇒ page 200 is adjusted
electronically according to road speed.
If a fault should occur in the servotronic system, the power steering will still
operate. The degree of power assistance will, however, no longer adapt to
different speeds. If the electronic regulating system is not working properly,
this is most noticeable when turning the steering wheel at low speeds (for
instance when parking), as more effort will be required than usual. The fault
should be corrected by a specialised workshop as soon as possible.
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Driving and the environment
WARNING (Continued)
● On steep slopes, if brakes are excessively used, they will overheat.
Before driving down a long steep slope, it is advisable to reduce speed
and change down into a lower gear or range (depending on the type of
transmission). This makes use of engine braking and relieves the brakes.
● Never let the brakes “drag” by applying light pressure. Continuous
braking will cause the brakes to overheat and the braking distance will
increase. Apply and then release the brakes alternately.
● Never let the vehicle run with the engine switched off. The braking
distance is increased considerably when the brake servo is not active.
● If the brake fluid loses its viscosity and is subjected to heavy use, va-
pour bubbles can form in the brake system. This reduces the efficiency of
the brakes.
● Non-standard or damaged front spoilers could restrict the airflow to
the brakes and cause them to overheat. Before purchasing accessories
please observe the relevant instructions ⇒ page 230, Technical modifi-
cations.
● If a brake system circuit fails, the braking distance will be increased
considerably. Contact a specialised workshop immediately and avoid un-
necessary journeys.
Exhaust gas purification system Catalytic converter*
To maintain the useful life of the catalytic converter
– Use only unleaded petrol with petrol engines, as lead damages
the catalytic converter.
– Do not let the fuel get too low in the tank. –
For engine oil changes, do not replenish with too much engine
oil ⇒ page 239.
– Never tow the vehicle to start it, use jump leads if necessary
⇒ page 295.
If you notice misfiring, uneven running or loss of power when the vehicle is
moving, reduce speed immediately and have the vehicle inspected at the
nearest specialised workshop. In general, the exhaust gas warning lamp
will light up when any of the described symptoms occur ⇒ page 68. If this
happens, unburnt fuel can enter the exhaust system and escape into the en-
vironment. The catalytic converter can also be damaged by overheating.
WARNING
The catalytic converter reaches very high temperatures! Risk of fire!
● Never park where the catalytic converter could come into contact with
dry grass or flammable materials under the vehicle.
● Do not apply additional underseal or anti-corrosion coatings to the
exhaust pipes, catalytic converter or the heat shields on the exhaust sys-
tem. These materials could catch fire when the vehicle is being driven.
CAUTION
Never run the fuel tank completely dry because the irregularity of the fuel
supply may cause ignition problems. This allows unburnt fuel to enter the
exhaust system, which could cause overheating and damage the catalytic
converter.
For the sake of the environment
Even when the emission control system is working perfectly, there 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 another brand of fuel.
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Driving and the environment
Avoid idling
It is worthwhile switching off the engine when waiting in a traffic jam, at lev-
el crossings or at traffic lights with a long red phase. The fuel saved after
only 30 - 40 seconds is greater than the amount of fuel needed to restart
the engine.
The engine takes a long time to warm up when it is idling. Mechanical wear
and pollutant emissions are also especially high during this initial warm-up
phase. It is therefore best to drive off immediately after starting the engine.
Avoid running the engine at high speed.
Periodic maintenance
Periodic maintenance work guarantees that, before beginning a journey,
you will not consume 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 value.
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 proportionally higher. The engine
does not warm up and fuel consumption does not normalise until having
driven approximately four kilometres (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 adequate pressure saves fuel. If
the tyre pressure is just one bar too low, fuel consumption can increase by
as much as 5%. Due to the greater rolling resistance, under-inflation also
increases tyre 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 increase the fuel consumption, it is
advisable to always check the luggage compartment to make sure that no
unnecessary loads are being transported.
A roof rack is often left in place for the sake of convenience, even when it is
no longer needed. At a speed of 100-120 km/h (60-75 mph) your vehicle
will use about 12% more fuel as a result of the extra wind resistance 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 electricity, fuel consumption is also increased. Because of this, al-
ways turn off electrical components when you do not need them. Examples
of components that use a lot of electricity are: the fan at high speeds, the
rear window heating or the seat heaters*.
Note
● If you vehicle has Start-Stop, it is not recommended to switch this func-
tion off.
● It is recommended to close the windows when driving at more than
60 km/h (40 mph)
● Do not drive with your foot resting on the clutch pedal, as the pressure
can make the plate spin, more fuel will be used and it can burn the clutch
plate lining, causing a serious fault.
● Do not hold the vehicle on a hill with the clutch, use the foot brake or
hand brake, using the latter to start. The fuel consumption will be lower and
you will prevent the clutch plate from being damaged.
● On descents, use the engine brake, changing to the gear that is more
suitable for the slope. The fuel consumption will be lower and the brakes
will not suffer.
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Driving and the environment
In vehicles with adaptive headlights, the rotation system must previously be
disconnected. To do this, please go to a specialised workshop.
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Trailer towing
Where possible, operate the trailer with the maximum permitted drawbar
load on the ball joint of the towing bracket, but do not exceed the specified
limit.
Tyre pressure
Check the tyre pressures on your vehicle, and adjust for “full load” condi-
tions (refer to the sticker listing the tyre pressures on the door pillar). It may
also be necessary to adjust the tyre pressures on the trailer according to the
recommendations of the trailer manufacturer.
Exterior mirrors
Check whether you can see enough of the road behind the trailer with the
standard mirrors. If this is not the case you should have additional mirrors
fitted. The two exterior mirrors should be fitted on folding arms. Adjust the
mirrors to give sufficient rear vision.
Headlights
Before starting a journey, check the headlight beam settings with the trailer
hitched up. If necessary, alter the height of the headlight beams by means
of the headlight range control. See ⇒ page 121.
Power supply
When you remove the ignition key, the power supply to the trailer is inter-
rupted.
Removable ball joint coupling
Vehicles with a factory-fitted towing bracket are equipped with a removable
ball joint coupling. This is stored in the spare wheel well in the luggage
compartment together with the necessary fitting instructions.
Note
If you frequently tow, we recommend you also have the vehicle serviced be-
tween services. Notes on towing
Towing a trailer involves additional attention by the driver.
Weight distribution
The weight distribution of a loaded trailer with an unladen vehicle is very
unfavourable. However, if this cannot be avoided, drive extra slow to allow
for the unbalanced weight distribution.
Speed
The stability of the vehicle and trailer is reduced with increasing speed.
Therefore, it is advisable not to drive at the maximum permissible speed in
unfavourable road, weather or wind conditions. This especially applies
when driving downhill.
You should always reduce speed immediately if the trailer shows the slight-
est sign of swaying. Never try to stabilise the trailer by accelerating.
Anticipate hazards and brake in good time. If towing a trailer with an inertia
brake, first brake gently and then harder. This will prevent brake tapping by
the trailer wheels when they lock. Select a low gear in due course before go-
ing down a steep downhill. This enables you to use the engine braking to
slow down the vehicle.
Swaying and pitching can be reduced by stabiliser aids. We recommend
having stabiliser aids installed when towing trailers with a high trailer
weight. They can be purchased and installed at a Technical Service.
Reheating
When climbing long hills in hot weather with the engine running fast in low
gear, you should keep an eye on the coolant temperature gauge ⇒ page 62.
Reduce speed immediately if the needle moves to the right end of the scale.
If the temperature warning lamp in the instrument panel should start
flashing, stop the vehicle and let the engine cool down by running it at
idling speed for a few minutes.
Safety FirstOperating instructionsPractical TipsTechnical Specifications