Intelligent Technology
197
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
vehicle and reduces the strain on the brakes
. Any additional braking should be done
intermittently, no
t continuously.
Note
The brake light flashes automa
tically in case of an em
ergency braking at speeds
g re a t e r t h a n 6 0 k m /h o r w i t h t he i n t e r v e n t i o n o f th e A BS , w h i ch l a s t s l o n g e r th a n 1 .5 seconds. After the speed was reduced belo
w 10 km/h or the vehicle was stopped,
the brake light stops flashing and the hazard warning light system switches on. The hazard warning light system is switched
off automatically after accelerating or
driving off again.Brake boosterThe 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 optima
lly 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 yo
ur 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 39.
•
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 241,
“Accessories, changes and replacement of parts”.
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Intelligent Technology
198
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. 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 maxi
mum 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 193.
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 th
e 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 steeringThe power steering enables you to steer
the vehicle with le
ss 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, the warning light
or lights up in the
instrument cluster
⇒page 36.
WARNING
Contact your specialist
garage if the power steering is defective.
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Intelligent Technology
200
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
, 7MB
or
7MG
on the vehicle data sticker, see
⇒
fig. 193
, indi-
cates 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
.WARNING
•
The diesel particle filter
achieves very high te
mperatures. 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 wi
ll be able to tell you which countries use
only diesel fuel with high sulphur content.
Fig. 193 Vehicle data sticker
WARNING (continued)
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Driving and the Environment
201
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
Driving and the EnvironmentA new engineThe 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 spee
d 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 tyresNew 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 padsAllow 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 increasing 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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Driving and the Environment
202
Catalytic converterProper operation of the emission co
ntrol system (catal
ytic 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 219, “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 225, “Replenishing
engine oil”.
– Do not tow-start the vehicle over a
distance of more than 50 metres
⇒
page 252, “Tow-starting and towing vehicle”.
If you drive your vehi
cle in a country in which unleaded
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 resu
lt in the catalytic
converter being destroyed.•
If you detect a power reduction or ir
regular engine runni
ng 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 into the ex
haust system and da
mage 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 op
erating conditions of the en
gine. 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 mannerGeneral 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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Driving and the Environment
203
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
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 obtained 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. 194
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 21.
Fig. 194 Fuel consumption in litres/100 km. and speed in km/h.
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Driving and the Environment
204
Avoiding full throttle Driving more slowly means saving fuel.Sensitive use of the accelera
tor will not only significantly reduce fuel consumption
but also positively influence environmen
tal pollution and wear of your vehicle.
You should avoid fully exploi
ting the top speed of your vehicle wherever possible.
Fuel consumption, pollutant emissions and vehicle noises increase disproportion- ally at high speeds. The
⇒fig. 195
shows the ratio of fuel consumption to the speed of your vehicle.
You will cut your fuel consumption by half
if you only make use three-quarters of
the possible top speed of your vehicle.Reducing idling Idling also costs fuel.It is worthwhile switching off the engine in
a traffic jam or when waiting at a level
crossing or at traffic lights with a length
y red phase. Even after just 30 - 40 seconds
you will have saved more fuel than that
is needed when you start the engine up
again. If an engine is only idling it takes much
longer for it to reach its normal operating
temperature. Wear-and-tear and pollutant em
issions, though, are particularly high
in the warming-up phase. This is why you
should drive off right after starting the
engine. Do avoid high engine re
volutions at this time, however.
Regular servicing A poorly tuned engine consumes an unnecessarily high amount of fuel.Having your vehicle serviced regularly at a specialist garge enables you to satisfy one
of the requirements for economical moto
ring even before you set off on your
journey. Keeping your vehicle properly servic
ed not only has a positive effect on the
safety of your vehicle and maintaining its value, but also saves on
fuel
.
A poorly tuned engine can result in a fu
el consumption which is 10% higher than
normal. The foreseen maintenance work should be undertaken exactly according to the Service schedule by a specialist garage. Also check the
oil level
after refueling.
Oil consumption
is dependent to a consid-
erable extent on the load and speed of
the engine. Oil consum
ption could be as
high as 0.5 litres/1 000 km depending on your style of driving. It is quite normal that a new engine ha
s a higher oil consumption at first, and
reaches its lowest level only
after a certain running in
time. It is therefore not
possible to correctly assess the oil cons
umption of a new vehicle until after you
have driven about 5 000 km.
For the sake of the environment
•
You can achieve additional improvements
in your fuel economy by using high-
lubricity oils.•
Check the ground below your car at regula
r intervals to detect any leakages in
good time. Please have your
vehicle inspected by a specialist garge if you find any
stains caused by oil or
other fluids on the floor.
Fig. 195 Fuel consumption in litres/100 km. and speed in km/h.
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Driving and the Environment
205
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
Avoid driving short distances Short distances result in an above-average high fuel consumption.– Avoid driving a distance of no more than 4 km if the engine is cold.The engine and catalytic converter mu
st first have reached their optimal
operating
temperature
in order to effectively reduce fu
el consumption and pollutant emis-
sions. The cold engine vehicle consumes approx. 15 - 20 litres/100 km of fuel immediately after starting. Fuel co
nsumption drops to 10 litres/100 km after just 1 kilometre. The
engine reaches its operating temperat
ure (outside temperature and engine
dependent) only after about
4 to 10
kilometres and the fuel consumption then
stabilizes. You should therefore avoid driving short distances whenever possible. An important factor in this connection is also the
ambient temperature
. The
⇒ fig. 196
shows the different fuel consumptions for the same distance, on the one
hand at +20°C and on the other hand at
-10°C. Your vehicle has a higher fuel
consumption in winter than in summer.Checking tyre inflation pressures Tyres which are correctly inflated save fuel.Always ensure that your tyres are inflated
to the correct pressure at all times. The
rolling resistance will be increased if the tyre filling pressure is too low. This will not
only increase fuel consumption but also
tyre wear and the driving behaviour will
worsen. Always check the inflation pressure of the tyres when
cold
.
Do not drive with
winter tyres
all year round for this costs about 10 % more fuel.
Winter tyres are also louder.No unnecessary ballast Transporting ballast costs fuel.The fact that every kilogram of extra
weight
increases your fuel consumption
means that it is worth taking a look in the luggage compartment to avoid trans- porting any unnecessary ballast. It is particularly in town traffic, when one
is accelerating quite often, that the vehicle
weight will have a significant effect upon
the fuel consumption. A rule of thumb
here is that an increase in weight of 100
kilograms will cause an increase in fuel
consumption of about 1
litre/100 kilometres.
You may frequently also leave a
roof rack fitted
on just out of convenience,
although you no longer need it. The incr
eased aerodynamic drag of your vehicle
causes it to use about 10% more fuel th
an normal at a speed of 100 - 120 km/h,
even when you are not carr
ying a load on the roof.
Saving electricity Generating electricity costs fuel.– Switch off electrical components as
soon as you no longer need them.
When the engine is running, the alternator
generates and supplies
electrical power.
The greater the load on the alternator as a result of having a large number of elec-trical components switched on, the more
fuel will be consumed for operating the
alternator.
Fig. 196 Fuel consumption in litres/100 km at different temperatures
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