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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. 150 . The
warning light in the button lights up. The warning light lights up in the instrument
cluster if the system is switched on
page 37.
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 equipment 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. 150 .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 37.
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.
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 engine of the vehicle is running, the selector lever of the automatic gearbox is
in the position R, N, D, S or Tiptronic,
the speed is less than 30 km/h,
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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 8 %.
Manual gearbox
The vehicle speed is steadily regulated by the Assist System depending on the type of
gearbox or engine:
1. gear - approx. 8
11) - 30 km/h
2. gear - approx. 13
11) - 30 km/h
3. gear - approx. 22
11) - 30 km/h
Reverse gear - approx. 9
11) - 30 km/h
Neutral for driving forwards - as well as driving backwards - approx. 2
11) - 30 km/h
Automatic gearbox
Selector lever in the position D, S or Tiptro nic (for the 1st, 2nd, 3rd gear) for driving
forwards - approx. 2 - 30 km/h
Selector lever in the position R for driving backwards - approx. 2 - 30 km/h
Selector lever in the position N for drivin g forwards as well as backwards - approx.
2 - 30 km/hNote
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.
11)The indicated values represent the average of the lower speed limits if a gear is engaged (de-
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Driving and the EnvironmentThe first 1 500 kilometres and then afterwardsA 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 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 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 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 avoid excessive stresses 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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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.
– 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 vehicle 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 and damage the cata lytic converter.
Filling the tank even only once with leaded 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 engine. This depends 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.
The technical requirements for low fuel usage and economic efficiency of the vehicle
have already been built into the vehicle at the works. Special attention has been given
to minimising negative effects on the environment. It is necessary to take note of the
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Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
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.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. 151 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.
Note
Also use the information supplied by the multi-functional indicator* page 20.Avoiding full throttle
Driving more slowly means saving fuel.Sensitive use of the accelerator will not only significantly reduce fuel consumption but
also positively influence environmenta l pollution and wear of your vehicle.
You should avoid exploiting the top speed of your vehicle wherever possible. Fuel
consumption, pollutant emissions and vehicl e noises increase disproportionally at
high speeds.
The fig. 152 shows the ratio between the fuel consumption and the speed of your
vehicle. You will cut your fuel consumption by half if you only make use three-quar ters
of the possible top speed of your vehicle.
Fig. 151 Fuel consumption in litres/100
km. and speed in km/h.
Fig. 152 Fuel consumption in litres/100
km. and speed in km/h.
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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 roadsIn 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. 154 .
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 generate 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.Note
After driving through a body of water, we recommend that the vehicle is checked by a
specialist garage.Off-road drivingImportant information
WARNING
Never drive too fast, particularly not around curves, and never undertake
extreme driving manoeuvres.
Always adjust your speed and adapt your style of driving to suit road, off-
road, traffic and weather conditions.
Fig. 154 Crossing bodies of water
WARNING (continued)
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Shifting gears correctlyThe gear you must shift into depends on th e terrain. Choosing the correct gear contrib-
utes to safe driving. In partic ular if you do not have much experience driving off-road,
it is always better, before negotiating a difficult stretch of the road, to pause and reflect
on which gear to engage. Your experience will tell you which gear is the best for certain
sections of the terrain.
Basically:
When the gear or the driving stage has been properly selected, it is unnecessary to
slow down the vehicle on a downhill sectio n using the footbrake as in most cases the
engine braking power is sufficient.
Depress the accelerator only as much as is necessary. A too great acceleration may
lead to the wheels spinning and thus results in the loss over the control of the vehicle.
Manual gearbox
If you are driving thro ugh difficult terrain, on no account use the clutch or change
the gear. When the clutch is depressed, th e vehicle may come to a standstill because
of the increased grip of all the tyres of the vehicle (e.g. in the mud, in deep sand or on
a slope). Once the vehicle has come to a stan dstill, it may be difficult or even impos-
sible to start off under these conditions.
When negotiating a steep downhill section or a steep uphill section, always shift
into the 1st or 2nd gear.
On a soft or slippery ground, you must drive at the appropriate speed and you
must select the highest possible gear for this.
Automatic gearbox
Select the selector lever position for normal flat stretches of terrain
page 121.
While in the Tiptronic mode, select the se lector lever position or if you are
driving through mud, sand, water or hilly sections of terrain page 123.
When negotiating a steep downhill section or a steep uphill section, select the
selector lever position while in the Tiptronic mode.
On a soft or slippery ground, you must drive at the appropriate speed and you
must select the highest possible driving stage.
Driving over rough and smooth– Switch on the Off-road mode page 170.
– Drive at walking speed over rocky passages.
– If it is not possible to drive around a stone, gently drive onto the stone with one of the front wheels and then drive over it slowly.
WARNING
Observe the important guidelines page 179.
Caution
On no account drive over large objects (suc h as pieces of rock or tree stumps),
neither in the middle nor on one side. When driving over objects which are larger than
the ground clearance, the chassis and its components can get damaged. Your vehicle
could break down far away from any assistance.
Even objects that are smaller than the existing ground clearance can come into
contact with the underbody of the vehicle an d can lead to damage or failure of the
vehicle. This applies especially when there is a hollow or soft ground in front or behind
the object or if you drive too fast over the object and thus the vehicle is deflected.For the sake of the environment
Leaking engine oil and brake fluid poll ute the environment and contaminate the
bodies of water. The disposal e.g. of engine oil soaked soil can be costly.
AD
A3
A2
A1
Fig. 157 Observe the ground clearance
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Crossing bodies of waterParticular attention is required when driving through bodies of water page 179.Driving through snow-covered terrain– Before you drive through snow-covered te rrain, mount snow chains on the front
wheels or on the rear wheels page 220, “Snow chains” in order to achieve the
best possible traction.
–Switch on the Off-road mode page 170.
Even harmless looking sections of terrain can be dangerous. This applies in particular
for sections where no ruts or other tracks are visible.
WARNING
Driving through snow-covered terrain poses special dangers. Never choose
a dangerous route and never take a risk which could jeopardize your safety and
that of your passengers. If you cannot go on or if you doubt the safety of the
route, turn back and choose another way.
Potholes, troughs, trenches, precipices , sheets of ice or other obstructions
are often completely or partially obscured by snow.
The hidden dangers of snow can cause an accident, serious injuries or your
vehicle to break down under extreme weather conditions.
Driving over steep terrainDriving uphill and downhill– Stop the vehicle before driv ing uphill or downhill, exit the vehicle and explore the
situation.
– Walk a stretch and check the firmness of the soil and look for obstructions or other hidden dangers.
– Check how the route continues beyond the slope.
–Switch on the Off-road mode page 170. – Drive slowly and steadily straight uphill or downhill.
– Do not stop the vehicle on a hillside or attempt to turn around.
– You must prevent the engine from cutting out.
Driving uphill– Check before driving over a hilltop, how it
continues on the other side. If you drive
up a steep hill, the vehicle faces the sky and you cannot see what is directly in front
of the vehicle.
– Switch on the Off-road mode page 170.
– Do not shift gears or release the clutch during the climbing phase.
– Depress the accelerator only as much as is necessary in order to handle the slope.If you can go no further on a slope– Never attempt to make a turn with the vehicle on a hillside.
– If the engine cuts out, press the foot brake and restart the engine.
– Engage the reverse gear and carefully drive backwards in your own tracks.
– Press the foot brake in order to maintain a constant speed.Driving downhill– Switch on the Off-road mode page 170.
– Shift into first gear or select the first driving stage, while in the Tiptronic mode, to drive downhill on steep hillsides in order to use the Downhill Drive Support to its
maximum.
– Press the foot brake gently, so you do not lose the control over your vehicle.
– If it is feasible and safe, drive straight down (maximum gradient).
– Do not release the clutch or shift into Neutral.
WARNING
Never attempt to drive uphill or downhill if it is too steep for your vehicle.
The vehicle could slip or roll over - risk of accident!
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