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WARNING
Even with this additional function the vehicle cannot be steered automati-
cally! The driver is furthermore fully reponsible for the steering of the
vehicle!
Brakes
What has a negative effect on braking efficiency?
Wear-and-tear
Wear-and-tear to the brake pads is greatly dependent on the operating conditions
of the vehicle and your style of driving. Particularly if you drive a great deal in towns
and over short distances or if you adopt a sporty style of driving, it may be neces-
sary to have the thickness of the brake pads inspected at a specialist garage
between the service inspections.
Wet roads or road salt
There may be a certain delay before the brakes take full effect under certain condi-
tions such as when driving through water, during heavy rain showers or after the
vehicle has been washed in an automatic vehicle wash, since the brake discs and
brake pads may be moist or even have a coating of ice on them in winter. You
should dry the brakes as soon as possib le (by applying and releasing the brakes
several times, if the road conditions and the traffic situation allows it).
There also may be a certain delay before the full braking efficiency is available when
driving on roads which have been treated wi th road salt if you have not used the
brakes for some considerable time beforeha nd. The layer of salt on the brake discs
and brake pads must first be rubb ed off when you apply the brakes.
Corrosion
Corrosion on the brake discs and dirt on th e bake pads occur if the vehicle has been
parked for a long period and if you do not make much use of the braking system.
We recommend cleaning the brake discs by firmly applying the brakes at a fairly
high speed if you do not make much use of the braking system or if surface corro-
sion is present ⇒. Faults in the brake surface
If you notice that the braking distance
has suddenly become longer and that the
brake pedal can be depressed further, it is possible that a brake circuit of the dual-
circuit brake system has failed. Drive, in such cases, to the nearest specialist garage
without delay in order to have the problem rectified. Drive at a reduced speed while
on your way to the dealer and adapt your style of driving to the higher brake pedal
pressure required.
Low brake fluid level
An insufficient level of brake fluid may result in problems in the brake system. The
level of the brake fluid is monitored electronically ⇒page 32, “Brake system ”.
WARNING
•Only apply the brakes for the purpos e of drying and cleaning the brake
discs if the traffic conditions permit this. Do not place any other road users
in jeopardy.
•When retrospectively mounting a front spoiler, solid wheel hubs etc. one
must ensure that the air supply to the front wheel brakes is not reduced
otherwise the braking sy stem could run too hot.
•Allow for the fact that new brake pads do not achieve their full braking
efficiency until approximately 200 kilo metres. New brake pads must be first
“run in” before they develop their optimal friction force. You can, however,
compensate for this slightly reduced braking force by increasing the pres-
sure on the brake pedal. This guidelin e also applies to any new brake pads
installed at a future date.
Caution
•Never allow the brakes to ru b by applying slight pressure if you do not wish to
brake the vehicle. This causes the brakes to overheat and can also result in a longer
braking distance and excessive wear.
•Before negotiating a steep downhill sect ion, please reduce your speed, shift
down into the next lower gear (manual ge arbox) or select a lower driving stage
(automatic gearbox). This enables you to make full use of the braking power of the
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vehicle and reduces the strain on the brakes
. Any additional braking should be done
intermittently, no t continuously.
Note
The hazard warning light system is switched on automatically in case of an emer-
gency braking at speeds greater than 60 km /h. The hazard warning light system is
switched off automatically after accelerating or driving off again.
Brake booster
The brake booster boosts the pressure which you generate with the brake pedal.
The necessary pressure is only gene rated when the engine is running.
WARNING
•Never switch off the engine before the vehicle is stationary.
•The brake booster only operates when the engine is running. Greater
physical effort for braking is required when engine is switched off. Because
if you do not stop as normal, this can cause an accident and severe injuries.
Antilock brake system (ABS)
ABS prevents the wheels locking when braking.
General
The ABS contributes significan tly to enhancing the active safety of your vehicle.
Compared to a car not fitted with the ABS brake system, you are able to retain
optimal steering ability even during a fu ll brake application on a slippery road
surface because the wheels do not lock up.
You must not expect, however, that the br aking distance will be shorter under all
circumstances as a result of the ABS. Th e braking distance for example on gravel
and fresh snow, when you should anyway be driving slowly and cautiously, will be
longer. Operating principle
The brake pressure will be reduced on a wheel which is rotating at a speed which is
too low for the speed of the vehicle and tend
ing to lock. This control cycle is notice-
able from a pulsating movement of the brake pedal which is accompanied by
noises. This is consciously intended to provide the driver with the information that
the wheels are tending to lock (ABS control range). You must always keep the brake
pedal depressed to enable the ABS to optimally control the brake application in this
braking range. Never interrupt the application of the brakes!
WARNING
•The ABS can also not overcome the physic al limits of your vehicle. Please
do not forget this, particularly when driv ing on icy or wet road surfaces. If the
ABS is operating within the control ra nge, adapt your speed immediately to
the conditions of the road surface and the traffic situation. The increased
safety offered by the ABS must not tempt you to take greater risks than
otherwise - risk of an accident!
•The normal braking system is still fully functional if there is an ABS fault.
Visit a specialist garage as quickly as po ssible and adjust your style of driving
to take account of the ABS fault in the meantime since you will not know how
great the damage is.
Note
•A warning light comes on if a fault occurs in the ABS system ⇒page 31.
•Changes to vehicle (e.g. on engine, on the brakes, on chassis or other assign-
ment of tyres and wheels) can in fluence the function of the ABS ⇒page 229,
“Accessories, changes and replacement of parts”.
Brake Assist*
During a severe brake application (e.g. if a hazard exists), the Brake Assist increases
the braking force and thus makes it possible to rapidly produce the pressure
required in the brake system.
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186
The majority of drivers do apply the brakes in good time in dangerous situations,
but do not depress the brake pedal with su fficient pressure. Consequently, it is not
possible for the car to achieve its maximum deceleration and the car covers a
greater distance than necessary.
The Brake Assist is activated by the very quick operation of the brake pedal. In such
cases, a much greater braking pressure ex ists than during a normal brake applica-
tion. This makes it possible, even with a relatively low resistance of the brake pedal,
to produce an adequate pressure in the brake system in the shortest possible time,
which is required for maximum deceleration of the car. You must apply the brake
pedal firmly and hold it in this position in order to achieve the shortest possible
braking distance.
The Brake Assist is able to help you achieve a shorter braking distance in emergency
situations by rapidly producing the pressure required in the brake system. It fully
exploits the attributes of the ABS. After you release the brake pedal, the function of
the Brake Assist is automatically switched off and the brakes operate in the normal
way.
The Brake Assist is part of the ESP system. If a fault occurs in the ESP, the Brake Assist
function is also not available. Further information on the ESP ⇒page 181.
WARNING
•The Brake Assist is also not able to overcome the physical limits of your
car in terms of the braking distance required.
•Adapt your speed to the conditions of the road surface and to the traffic
situation.
•The increased safety offered by the Brake Assist must not tempt you to
take a greater safety risk than otherwise.
Uphill-Start off-Assist*
The uphill-start off-assist makes it much easier to start off on steep hills. The system
assists a start off by holding the brake pr essure produced by the brake pedal actu-
ation for approx. 2 seconds after releasing the brake pedal. The driver can therefore
move his foot from the brake pedal to the accelerator pedal and start off on the slope, without having to actuate the hand
brake. The brake pressure drops gradually
the more you operate the accelerator pedal. If the vehicle does not start off within
2 seconds, it starts to roll back.
The uphill-start off-assist is active in the ev ent of a 5% slope, if the vehicle door is
closed. It is alwa ys active on slopes when in forward or reverse start off. When
driving downhill, it is inactive.
Electromechanical power steering
The power steering enables you to steer the vehicle with less physical force.
With the electromechanical power steering, the steering assist is automatically
adapted to the speed and to the steering angle.
It is still possible to fully steer the vehicle if the power steering fails or if the engine
is not running (vehicle being towed in). The only difference is that greater physical
effort is required.
If there is a fault in the power steering, a red or yellow warning light
lights up in
the instrument cluster ⇒page 27.
WARNING
Contact your specialist garage if the power steering is defective.
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Tyre inflation pressure-control system*
The tyre inflation pressure-control system compares with the aid of the ABS sensors
the speed and also the rolling circumference of the individual wheels. If the rolling
circumference of a wheel is changed, the warning light
lights up in the dash
panel insert ⇒page 30. The rolling circumference of the tyre can change if:
•the tyre inflation pressure is too low,
•the structure of the tyre is damaged,
•the vehicle is loaded on one side,
•the wheels of an axle are loaded heavily (e.g. when towing a trailer or when
driving uphill or downhill),
•snow chains are mounted,
•the temporary spare wheel is mounted,
•one wheel per axle was changed.
Basic setting of tyre inflation pressure-control system
After changing the tyre inflation pressures or after changing one or several wheels,
a basic setting of the system must be carried out as follows.
•Inflate all tyres to the specified inflation pressure ⇒page 223.
•Switch on the ignition.
•Press button ⇒ fig. 186 for more than 2 second s. While pressing the
button, the warning light lights up. At the same time the basic values are stored,
which is confirmed with an acoustic sound and then the warning light goes out.
•If the warning light does not go out after the basic setting, there is a fault in
the system. Have the vehicle inspected by your nearest specialist garage.
Warning light
lights up
If the tyre inflation pressure of at least on e wheel is insufficiently inflated in compar-
ison to the stored basic value, the warning light
⇒ lights up.
Warning light
flashes
If the warning light flashes, there is a system fault. Have the vehicle inspected by
your nearest specialist garage.
WARNING
•When the warning light lights up, immediately reduce the speed and
avoid sudden steering and brake mano euvres. Please stop the vehicle
without delay at the nearest possible stop and inspect the tyres and their
inflation pressures.
•The driver is responsible for the correc t tyre inflation pressures. For this
reason, the tyre inflation pressures must be checked regularly.
•Under certain circumstances (e.g. sporty style of driving, wintry or
unpaved roads) the warning light can be delayed or does not light up at
all.
•The tyre inflation pressure-control system does not take away the
responsability from the driver for the correct tyre inflation pressure.
Note
The tyre inflation pressure-control system:
•does not replace the regular tyre inflatio n pressure control, because the system
cannot detect an even pressure loss,
•cannot warn in case of very rapid tyre inflation pressure loss, e.g. in case of
sudden tyre damage. In this case carefully bring the vehicle to a standstill without
sudden steering movements and without sharp braking.
Fig. 186 Button for
setting the tyre inflation
pressure control value
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188
Diesel particle filter* (diesel engine)
In the diesel particle filter the resulting soot particles are collected
and burnt during the combustion of diesel fuel.
Code 7GG on the vehicle data sticker ⇒fig. 187 indicates that your
vehicle is equipped with a diesel particle filter. The vehicle data sticker is
located on the floor of the luggage compartment and is also stated in the
Service schedule.
The diesel particle filter filters the soot particles completely from the exhaust. The
soot is collected in the diesel particle filter and burnt regularly. To assist this proce-
dure, we recommend not to drive regularly over short distances.
If the diesel particle filter is clogged or there is a fault, it is indicated by the warning
light
⇒ page 26, “Diesel particle filter* (diesel engine)”.
WARNING
•The diesel particle filter achieves very high temperatures. Therefore do
not park at points where the hot filter comes into direct contact with dry
grass or other combustible materials - risk of fire!
•Never use additional underbody protection or corrosion-protection
agents for the exhaust pipes, catalytic converters, diesel particle filter or
heat shields. When the engine reaches its operating temperature, these
substances might ignite - risk of fire.
Note
•When using diesel fuel with high sulphur content the life of the diesel particle
filter is clearly reduced. A specialist garage will be able to tell you which countries
use only diesel fuel wi th high sulphur content.
Fig. 187 Vehicle data
sticker
WARNING (continued)
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Driving and the Environment
The first 1 500 kilometres and then afterwards
A new engine
The engine has to be run in during the first 1 500 kilometres.
Up to 1 000 kilometres
– Do not drive faster than 3/4 of the mamimum speed of the gear in use,
that is 3/4 of the maximum permissible engine speed.
– Do not use full throttle.
– Avoid high engine revolutions.
– Do not tow a trailer.
From 1 000 up to 1 500 kilometres
– Increase the power output of the engine gradually up to the full
speed of the gear engaged, that is up to the maximum permissible
engine revolutions.
During the first operating hours the engine has higher internal friction than later
until all of the moving parts have harmonized. The driving style which you adopt
during the first approx.1 500 kilometres plays a decisive part in the success of
running in your car.
You should not drive at unnecessarily high engine revolutions even after the
running-in period is complete. The maximum permissib le engine speed is marked
by the beginning of the red zone on the scale of the revolutions counter. Shift up
into the next higher gear on a vehicle fitted with manual gearbox before the red
zone is reached. Extremely high engine revolutions are automatically governed, by
the way.
For a vehicle fitted with a manual gearbox the converse situation also applies: Do
not drive at engine revolutions which are too low. Shift down as soon as the engine
is no longer running smoothly.
Caution
All the speed and engine revolution figure s apply only when the engine is at its
normal operating temperature. Never rev up an engine which is cold, neither when
the vehicle is stationary nor when driving in individual gears.
For the sake of the environment
Not driving at unnecessarily high engine revolutions and shifting to a higher gear as
early as possible are ways to minimise fuel consumption and operating noise levels
and protects the environment.
New tyres
New tyres have to be “run in” since they do not offer optimal grip at first. You should
take account of this fact for the first 500 kilometres and drive particularly carefully.
New brake pads
Allow for the fact that new brake pads do not achieve their full braking efficiency
until approximately 200 kilometres. New brake pads must be first “run in” before
they develop their optimal friction force. You can, however, compensate for this
slightly reduced braking force by increa sing the pressure on the brake pedal.
This guideline also applies to any new brake pads installed at a future date.
During the running-in period , you should avoid excessive stresses on the brakes.
This includes, for example, violent braking, particularly from very high speeds, and
also when crossing mountain passes.
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Catalytic converter
Proper operation of the emission co ntrol system (catalytic converter)
is of major significance for drivin g your vehicle in an environmen-
tally conscious way.
Please refer to the following guidelines:
– For vehicles with petrol engine only refuel with unleaded petrol
⇒ page 206, “Grades of petrol”.
– Never run the fuel tank completely empty.
– Do not switch off the ignition while you are driving the vehicle.
– Do not pour too much oil into the engine ⇒page 213, “Replenishing
engine oil”.
– Do not tow-start the vehicle over a distance of more than 50 metres
⇒ page 242, “Tow-starting a vehicle”.
If you drive your vehi cle in a country in which unleade d petrol is not available, you
must have the catalytic converter replaced later when driving the vehicle into a
country in which use of a cata lytic converter is mandatory.
WARNING
•In view of the high temperatures which may be produced in the catalytic
converter, one should always park a vehicle in such a way that the catalytic
converter cannot come into contact with easily flammable materials below
the vehicle - a risk of fire!
•Never use additional underbody protection or corrosion-protection
agents for the exhaust pipes, catalyti c converters or heat shields. Such
substances might ignite when driving - risk of fire!
Caution
•Vehicles fitted with catalytic converter should neve r be allowed to let the fuel
tank to run completely empty. An irregular fuel supply can result in poor ignition or misfiring. Unburnt fuel may get into the exhaust system and damage the catalytic
converter.
•Filling the tank even only once with le
aded petrol will result in the catalytic
converter being destroyed.
•If you detect misfiring, a drop in perf ormance or irregular engine running when
driving, reduce your speed immediately and have the vehicle inspected by the
nearest specialist garage. The symptoms described may be caused by a fault in the
ignition system. Unburnt fuel may get in to the exhaust system and damage the
catalytic converter.
For the sake of the environment
Even if the exhaust system is operating properly, a sulphur-like exhaust odour may
be produced under certain operating condit ions of the engine. This depends on the
sulphur content of the fuel. It is often su fficient to refuel with unleaded premium-
grade petrol of a different brand or at a different filling station.
Driving in an economical and environmentally
conscious manner
General
Your personal style of driving is a major factor.
Your fuel consumption, any pollution of the environmental and the wear-and-tear
to the engine, brakes and tyres, depend essentially on three factors:
•your personal style of driving,
•the conditions under which your vehicle is operated,
•technical aspects.
You can easily improve your fuel economy by 10 - 15 percent by driving in an
economical way with foresight. This section is intended to provide you with a
number of tips on how to protect the en vironment and at the same time save
money.
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The fuel consumption can naturally also be
influenced by factors which are beyond
the driver's control. It is, for example, normal for the fu el consumption to increase
in winter and under worsened conditions such as poor road conditions, towing a
trailer, etc.
The technical requirements for low fuel usage and economic efficiency of the
vehicle have already been built into the ve hicle at the works. Special attention has
been given to minimising ne gative effects on the environment. It is necessary to
take note of the guidelines given in this chapter in order to make best use of these
characteristics and to maintain their effectiveness.
The optimal engine speed should be obtain ed when accelerating, in order to avoid
a high fuel consumption an d resonance of the vehicle.
Looking ahead when driving
A vehicle's highest fuel consumption occurs it accelerates.
Avoid accelerating and brakin g unnecessarily. If you drive with forsight you will not
need to brake so often and will also then not have to accelerate so much. Let your
vehicle coast to a stop, for example, if this is possible, when you see that the next
set of traffic lights is at red.
Shifting gears and saving energy
Shifting up early saves on fuel.
Manual gearbox
– Drive no more than about one length of your vehicle in first gear.
– Always shift up into the next higher gear at approx. 2 000 to 2 500 revs.
Automatic gearbox
– Depress the accelerator pedal slowly. Do not depress it beyond the
kickdown position, however.
An effective way of achieving good fuel economy is to shift up early. You will
consume more fuel if you drive at unnecessa rily high revolutions in any given gear.
The ⇒fig. 188 shows the ratio of fuel consumption to the speed of your vehicle in
the relevant gears. Fuel consumption in 1st gear is the highest, while that in 5th or
the 6th gear is the lowest.
Only depress the accelerator pedal slowly if your vehicle is fitted with an automatic
gearbox in order to automatically select an economic driving programme. You will
achieve good fuel economy by shifting up early and shifting down late.
Note
Also use the information supplied by the multi-functional indicator* ⇒page 14.
Fig. 188 Fuel consump-
tion in litres/100 km. and
speed in km/h.
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