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166
Active driver-steering recommendation (DSR)*Vehicles with ESP are equipped with active driver-steering recommendation (DSR). This function indicates to the driver in critical situations a steering recommendation in order to stabilise the vehicle. The active driver-steering recommendation is activated, for example, on the right and left vehicle si
de when braking sharply on different road
surfaces.
WARNING
Even with this function the vehicle canno
t steer itself! The dr
iver is furthermore
responsible for the steering of the vehicle!BrakesWhat 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. Particul
arly if you drive a great deal in towns and
over short distances or if you adopt a sporty style of driving, it may be necessary 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 conditions
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 coatin
g of ice on them in winter.
Yo u s h o u l d d r y t h e b r a k e s a s
soon as possible by applying and
releasing the brakes several times.
There also may be a certain delay before the full braking efficiency is available when driving on roads which have been treated with
road salt if you have not used the brakes
for some considerable time beforehand. The layer of salt on the brake discs and brake pads must first be rubbed 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 firm
ly applying the brakes at a fairly high
speed if you do not make much use of the braking system or if surface corrosion 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 possib
le 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 rectifie
d. 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 37, “Brake system
”.
WARNING
•
Only apply the brakes for the purpose of
drying and cleaning the brake discs
if the traffic conditions permit this. Do not place any other road users in jeop-ardy.•
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 other-wise the braking system could run too hot.•
Allow for the fact that new brake pads
do not achieve their full braking effi-
ciency until approximately 200 kilometres. New brake pads must be first “run in” before they develop their optimal fric
tion force. You can, however, compen-
sate for this slightly reduced braking fo
rce by increasing the pressure on the
brake pedal. This guideline also applie
s to any new brake pads installed at a
future date.
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167
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
Caution
•
Never allow the brakes to rub by applying sl
ight pressure if you do not wish to brake
the vehicle. This causes the br
akes to overheat and can also result in a longer braking
distance and excessive wear.•
Before negotiating a steep downhill section, please reduce your speed, shift down
into the next lower gear (manual gearbox)
or select a lower driving stage (automatic
gearbox). This enables you to make full us
e of the braking power of the vehicle and
reduces the strain on the brakes. Any additional braking should be done intermittently, not continuously.
Note
The brake light flashes automatically in case
of an emergency braking at speeds greater
than 60 km/h or with the intervention of the ABS, which lasts longer than 1.5 seconds. After the speed was reduced below 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 genera
ted 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 phys-
ical effort for braking is required when en
gine 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 significantly to enhanc
ing the active safety of your vehicle.
Compared to a vehicle not fitted with the ABS brake system, you are able to retain optimal steering ability even during a full br
ake 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. The braking distance for example on gravel and fresh snow, when you should anyway be driv
ing 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 tending
to lock. This control
cycle is noticeable
from a
pulsating movement of the brake pedal
which is accomp
anied 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! ABS Off-road* After switching on the Off-road mode
⇒page 170, ABS Off-road is activated.
ABS Off-road increases the braking power of
the vehicle on an unfirm ground, as it
keeps the wheels blocked for a longer period
of time when the brake is applied while
sliding. The system is only available, if the front wheels are in the straight-ahead posi-tion. The system operates at speeds of up to 50 km/h.
WARNING
•
The ABS can also not overcome the physical
limits of your ve
hicle. Please do
not forget this, particularly when driving on icy or wet road surfaces. If the ABS is operating within the control range, adapt your speed immediately to the conditions of the road surface and the traffic situation. The increased safety
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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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169
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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Intelligent Technology
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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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
HeadlightThe low beam of your headlights is set asymmetrically. It illuminates the side of the road on which you are driving to a greater ex
tent. If you drive abroad on the other side
of the road, you will
dazzle oncoming traffic.
In order to prevent the dazzling of oncoming traffic, it is necessary that an adjustment of the headlights is carried out by a specialist garage. The adaptation of the headlights with Xenon
lights* (applies only to
vehicles which are
designed for driving on the right and on the left) is performed in the menu
Setup
Tr a v e l m o d e
in the main menu of the Information display*
⇒page 24.
Note
You can obtain further information regarding masking over the headlights from a specialist garage.Avoiding damage to your vehicleWhen driving on poor roads and lanes or
when driving over kerbstones, steep ramps
etc., you must pay particular attention to
ensuring that any low-slung parts of the
vehicle, such as spoiler and exhaust,
do not touch the ground and get damaged.
This particularly applies to
models with a lowered suspen
sion (sport suspension) and
also when your vehicle is fully laden.Driving through bodies of water on roads
In order to avoid damage to the vehicle wh
en driving through bodies of water (e.g.
flooded roads), observe the following:•
Determine the depth of the water when driv
ing through bodies of water. The water
can reach at the maximum the web on the lower sill of the vehicle
⇒fig. 162
.
•
Drive no more than at walking speed. At a higher speed, a water wave can form in
front of the vehicle which can cause water to
penetrate into the air induction system of
the engine or into other parts of the vehicle.•
Never let the vehicle stand in the water,
never drive backwards and do not switch
off the engine.
WARNING
•
Driving through water, mud, sludge etc. can reduce the braking power and
extend the braking distance - risk of accident!•
Avoid sudden and severe braking manoeuvres immediately after driving
through bodies of water.•
After driving through bodies of water, the brakes must be cleaned and dried
as soon as possible by intermittent braking. Only apply the brakes for the purpose of drying and cleaning the brake
discs if the traffic conditions permit
this. Do not place any other road users in jeopardy.
Caution
•
When driving through bodies of water, pa
rts of the vehicle such as the engine,
gearbox, catalytic converter, chassis
or electrics can be severely damaged.
•
Oncoming vehicles can gene
rate water waves which ca
n exceed the permissible
water level for your vehicle.•
Potholes, mud or rocks can be
hidden under the water making it difficult or impos-
sible to drive through the body of water.•
Do not drive through salt water. The salt
can lead to corrosion. Immediately rinse
all the parts of the vehicle, which came into
contact with the salt water, with fresh
water.
Fig. 162 Crossing bodies of water
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