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168
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 poss
ible and adjust your style of driving to
take account of the ABS fault in the meantime since you will not know the extent of the fault and in how far the braking efficiency is affected.
Note
•
A warning light comes on if a fault occurs in the ABS system
⇒page 36.
•
Changes to vehicle (e.g. on engine, on th
e brakes, on chassis or another combina-
tion of tyres and wheels) can in
fluence the function of the ABS
⇒page 221, “Accesso-
ries, 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. The majority of drivers do apply the brakes
in good time in dangerous situations, but
do not depress the brake pedal with sufficient
pressure. Consequently, it is not possible
for the vehicle to achieve its maximum deceleration and the vehicle 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 exists
than during a normal
brake application.
This makes it possible, even with a relative
ly 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 th
e vehicle. 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 163.
WARNING
•
The Brake Assist is also not able to overcome the physical limits of your
vehicle in terms of the braking distance required.•
Adapt your speed to the conditions of th
e road surface and to the traffic situ-
ation.•
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 pressure produced by the brake pedal actuation 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 handbrake. 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 3 % slope, if the vehicle door is
closed. It is always 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 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.
WARNING (continued)
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Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
If there is a fault in the power steering, the warning light
or lights up in the instru-
ment cluster
⇒page 32.
WARNING
Contact your specialist
garage if the power steering is defective.
Tyre inflation pressu
re-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 instrument
cluster
⇒page 35 and an audible signal sounds.
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, the position of a wheel on the vehicle (e.g. ex
changing the wheels between the axles) or
when the warning light lights up while drivin
g, a basic setting of the system must be
carried out as follows.•
Inflate all tyres to the specified inflation pressure
⇒page 215.
•
Switch on the ignition.
•
Press button
⇒fig. 156
for more than 2 seconds. While pressing the button,
the warning light
lights up. At the same time the memory of the system is erased
and the new calibration is started, which is confirmed with an audible signal 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 one
wheel is insufficiently inflated in comparison
to the stored basic va
lue, 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 manoeuvr
es. Please stop the vehicle without
delay at the nearest possible stop and in
spect the tyres and their inflation pres-
sures.•
The driver is responsible for the correc
t tyre inflation pressures. For this
reason, the tyre inflation pressu
res 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 respon-
sability from the driver for the
correct tyre inflation pressure.
Fig. 156 Button for setting the tyre infla- tion pressure control value
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170
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.•
In order to ensure a proper functioning
of the tyre inflation pressure-control
system, it is necessary to carry out the basic setting again every 10 000 km or 1x a year.Diesel particle filter* (diesel engine)In the diesel particle filter the resu
lting soot particles are collected and
burnt during the combustion of diesel fuel.Code
7GG
, 7MB
or 7MG
on the vehicle data sticker, see
⇒fig. 157
, indicates that your
vehicle is equipped
with a diesel particle filter. The ve
hicle 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 procedure, we
recommend not to drive regu
larly 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 temp
eratures. 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 cont
ent 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 with high sulphur content.Off-road*GeneralThe Off-road mode comprises functions which assist off-road driving. The following functions are integrated in the Off-road mode:•
Start-Off Assist
⇒page 171,
•
Downhill Drive Support
⇒page 171,
•
EDL Off-road
⇒page 164,
Fig. 157 Vehicle data sticker
Fig. 158 Off-road switch
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Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
•
TCS Off-road
⇒page 165,
•
ABS Off-road
⇒page 167.
Switch on Off-road The Off-road mode is switched on by pressing the button
⇒page 170, fig. 158
. The
warning light in the button lights up. The wa
rning light lights up in the instrument
cluster if the system is switched on
⇒page 38.
Switch off Off-road The Off-road mode is switched off by repe
ated pressing of the button. The warning
light in the button goes out. When switching
off the ignition, the Off-road mode is also
switched off and can be switched on again, if necessary, after switching on the ignition. If the engine is switched off by accident an
d restarted within 30 seconds, the Off-road
mode remains switched on. All four wheels must be fitted with the same tyres in order to achieve proper operation of the Off-road mode. Differing rolling circum
ferences of the tyres can lead to an unde-
sirable reduction in the engine output.
WARNING
•
Always adjust your speed to suit weat
her, road and traffic conditions. The
increased safety must not tempt you to take a greater safety risk than otherwise - risk of accident!•
The Off-road equipment can also not overcome the physical limits of your
vehicle.•
The effect of the Off-road equipm
ent depends as well on the tyres.
•
The Off-road equipment
is not designed for the use on common roads.
Start-Off Assist*The Start-Off Assist enhances the driving comfort and can be used when starting off, in particular on a slope. When the vehicle is stationary, the Start-Off Assist is activated after switching it on using the button for the Off-road mode
⇒page 170, fig. 158
.
Operating principle When depressing the accelerator pedal fully, the engine speed required for the start- up procedure of the stationary vehicle is restricted. The overspeed trip unit is automat-ically deactivated after terminating the start-up procedure. As part of the Assist System, the accelerator pedal is adapted in its characteristics for an easier start-off on slippery and loose soil.Downhill Drive Support*Operating principle The Downhill Drive Support maintains a cons
tant speed on a steep downhill section
when driving forwards and backwards by
automatically intervening in the brake
system of all wheels. It prevents the wheels locking because the ABS remains active. The warning light
in the information display of the instrument cluster indicates that
the Downhill Drive Support is available
⇒page 38.
The vehicle speed, which is maintained by the Assist System, is selected by the driver while driving on a downhill section as of the
moment the first intervention of the Assist
System is performed or else, while driving on a downhill section, the driver must control the vehicle speed until the Assist System intervenes for the first time. When the Assist System actively intervenes, this is indicated by the warning light flashing or by a pulsating movement of the brake pedal,
similar to the intervention of the ABS.
The Downhill Drive Support is available in the speed range of 2 km/h up to 30 km/h. If the gear is engaged and the clutch pedal is
not pressed, the lower limit of the idling
speed corresponds to the respective gear which is engaged. You can increase or reduce the speed, even when no gear is engaged, by operating the accelerator or brake pedal. Thus the function
is always interrupted and is reactivated
afterwards. The Downhill Drive Support is activated auto
matically if the following conditions are
met:•
the Off-road mode is switched on and the warning light
lights up in the instru-
ment cluster,•
the engine of the vehicle is running and either the 1st, 2nd, 3rd gear, the reverse
gear or no gear is engaged,•
the speed is less than 30 km/h,
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Intelligent Technology
172
•
the downhill gradient is at least 10% (w
hen driving over sleepers the limit can
briefly drop to 8%),•
neither the accelerator nor the brake pedal is operated.
It is however a requirement that the vehicle
has sufficient grip on the soil. The Downhill
Drive Support cannot properly fulfil its functi
on on slushy soil due to physical reasons
(ice or mud). The Downhill Drive Support is deactivated wh
en braking or accelerating or if the
downhill gradient is less than 10%.
Note
•
During an intervention of the Downhill Drive Support, the brake lights do not light
up.•
Do not switch off the Off-road mode during an intervention of the Assist System.
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Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
Driving and the EnvironmentThe first 1 500 kilometres and then afterwardsA new engine The engine has to be run in du
ring the first 1 500 kilometres.
Up to 1 000 kilometres– Do not drive faster than 3/4 of the maximum speed of the gear in use, that is 3/4 of
the maximum permissi
ble 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 maxi
mum permissible engine revolutions.
During the first operating hours the engine ha
s higher internal friction than later until
all of the moving parts have harmonized. Th
e driving style which you adopt during the
first approx.1 500 kilometres plays a decisive
part in the success of running in your
vehicle. You should not drive at unnecessarily
high engine revolutions
even after the
running-in period is complete
. The maximum permissible en
gine 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 vehi
cle fitted with manual gear
box 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 figures ap
ply 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 unnecessari
ly high engine revolutions and
shifting to a higher gear as
early as possible are ways to minimise fu
el consumption and op
erating 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 pa
rticularly carefully.
New brake padsAllow for the fact that new brake pads do no
t 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 ca
n, 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 pe
riod, you should avoi
d excessive stre
sses on the brakes. This
includes, for example, violent braking, part
icularly from very high speeds, and also
when crossing mountain passes.
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174
Catalytic converterProper operation of the emission cont
rol system (catalytic converter) is
of major significance for driving your vehicle in an environmentally conscious way.Please refer to the following guidelines: – For vehicles with petrol engine only refuel with unleaded petrol
⇒page 200,
“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 206, “Replenishing engine oil”.
– Do not tow-start the vehicle over a distance of more than 50 metres
⇒page 230,
“Tow-starting and towing vehicle”.
If you drive your vehicle in a country in
which unleaded petrol is not available, you
must have the catalytic converter replaced la
ter when driving the ve
hicle into a country
in which use of a catalyti
c 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, catalytic converters or heat shields. Such substances might ignite when driving - risk of fire!
Caution
•
On vehicles fitted with a catalytic converte
r, never let the fuel tank run completely
empty. An irregular fuel supply can result in poor ignition or misfiring. Unburnt fuel may get into the exhaust system an
d damage the cata
lytic converter.
•
Filling the tank even only once with lead
ed petrol will result in the catalytic
converter being destroyed.•
If you detect misfir
ing, a drop in performance or
irregular engine running when
driving, reduce your speed immediately and have the vehicle inspected by the nearest specialist garage. The symptoms described ma
y be caused by a fault in the ignition
system. Unburnt fuel may get into the exhaust system and damage the catalytic converter.
For the sake of the environment
Even if the exhaust system is operating pr
operly, a sulphur-like exhaust odour may be
produced under certain oper
ating conditions of the en
gine. This de
pends on the
sulphur content of the fuel. It is often sufficient 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 econom-
ical way with foresight. This section is intended to provide you with a number of tips on how to protect the environment and at the same time save money. The fuel consumption can naturally also be
influenced by factors which are beyond the
driver's control. It is, for example, normal
for the fuel consumption to increase in
winter and under worsened cond
itions such as poor road conditions, towing a trailer,
etc.
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Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
The technical requirements for low fuel usage and economic efficiency of the vehicle have already been built into the vehicle at
the works. Special atte
ntion has been given
to minimising nega
tive 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 and
resonance of the vehicle.
Looking ahead when driving A vehicle's highest fuel consumption occurs it accelerates.Avoid accelerating and braking 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.Fig. 159 Fuel consumption in litres/100 km. and speed in km/h.Manual gearbox– Drive no more than about one length of your vehicle in first gear. – 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 unnecessaril
y high revolutions in any given gear.
The
⇒fig. 159
shows the ratio of fuel consumption
to the speed of your vehicle in the
relevant gear. Fuel consumption in 1st gear
is the highest. The consumption is the
lowest in the highest gear. You will achieve good fuel economy by shif
ting up early and shifting down late.
Shift recommendation
for changing gears*
An information for the engaged gear
⇒fig. 159
is shown in the display of the
instrument cluster. In order to minimise the fuel consumptio
n, a recommendation for shifting into
another gear is indicated in the display. If the control unit recognises
that it is appropriate to change the gear, an arrow is
shown in the display. The arrow points up or down, depending on whether it is recom- mended to shift into a higher or lower gear. At the same time, the recommended gear is indicated instead of the currently engaged gear .
Note
Also use the information supplied by the multi-functional indicator*
⇒page 20.
AA
AB
AA
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