
174Driving
Setting the speed
The desired cruising speed has to be stored in the memory.
Fig. 140 Controls for the
cruise control system
– Drive at the desired speed.
– Pull the lever A
to position ⇒ fig. 140 1 to activate the sys-
tem.
– Briefly press button B
.
When button B
is released, the current speed is stored in the memory and
the vehicle will then maintain this speed. Adjusting the stored speed
The desired cruising speed can be adjusted up or down as
required.
Acceleration
– Move the lever A
up towards
⇒ fig. 140 +.
– Release the lever to store the current cruising speed.
Deceleration
– Move the lever A
down towards
⇒ fig. 140 -.
– Release the lever to store the current cruising speed.
Pressing lever A
briefly
– You can increase the set speed in steps of 2 km/h by briefly
pressing the lever A
up towards
⇒ fig. 140 +.
– You can decrease the set speed in steps of 2 km/h by briefly
pressing the lever A
down towards
⇒ fig. 140 -.
You can also use the accelerator pedal momentarily to increase speed. The
previously programmed speed will be automatically resumed when the ac-
celerator pedal is released.
However, if the vehicle exceeds the programmed speed by more than 10
km/h for more than 5 minutes, the programmed speed will be deleted. You
will then need to enter the speed again.

179
Driving
To move the selector lever to position R, press in the interlock button and at
the same time press the brake pedal. Depending on the model, one or two
reverse lights will come on in selector lever position R (when ignition is
switched on).
N - Neutral (idling)
In this position the gearbox is in neutral ⇒
.
D - Drive (forward)
In this position, the gearbox selects the optimal transmission ratio depend-
ing on the engine load, speed and the dynamic gear regulation programme
(DRP).
Press the brake pedal when moving the selector lever from N to D if the ve-
hicle is stationary or at speeds below 5 km/h ⇒
.
Under certain circumstances (e.g. when driving in mountains or towing a
trailer or caravan) it can be advantageous to switch temporarily to tiptronic
mode ⇒ page 182, so that the gear ratios can be selected manually to suit
the driving conditions.
S - Sport position
To drive in sports mode, select the position S. The engine power reserve is
used to its maximum. When accelerating the gear shifts will be noticeable.
Press the brake pedal when moving the selector lever from N to S if the vehi-
cle is stationary or at speeds below 5 km/h ⇒
.
WARNING
● Never move the selector lever to R or P when driving. Failure to do so
could result in an accident.
● In selector position D or S the vehicle must always be held with the
foot brake when the engine is running. This is because an automatic
gearbox still transmits power even at idling speed, and the vehicle tends
WARNING (Continued)
to “creep”. The throttle must on no account be opened inadvertently (for
instance by hand from the engine compartment) when a gear is engaged
with the vehicle stationary. The vehicle could otherwise start moving im-
mediately (in some cases even if the parking brake is engaged) and pos-
sibly cause an accident.
● To avoid accidents, apply the parking brake and put the selector lever
in position P before opening the bonnet and working on the vehicle with
the engine running. Please observe the important safety warnings
⇒ page 221, Work in the engine compartment.
Note
● Applies to vehicles with tiptronic gearbox:
● If the lever is moved accidentally to N when driving, release the accelera-
tor and let the engine speed drop to idling before selecting D or S again.
● For the sake of fuel economy (and the environment), the gearbox ratios
on some models are designed so that maximum speed is only obtained
when the gear lever is in position S.
Safety FirstOperating InstructionsPractical TipsTechnical Specifications

188Intelligent technology
Brakes
General notes
New brake pads
New brake pads do not provide optimal performance during the first 200
km; first they must be “run in”. However, the reduced braking capacity may
be compensated by pressing on the brake pedal a little harder. Avoid over-
loading the brakes during run-in.
Wear
The rate of wear on the brake pads depends a great deal on how you drive
and the conditions in which the vehicle is operated. Negative factors are, for
instance, city traffic, frequent short trips or hard driving with abrupt starts
and stops.
Wet roads or road salt
In certain conditions, such as in heavy rain, or after washing the vehicle or
driving through water, the full braking effect can be delayed by moisture (or
in winter by ice) on the discs and brake pads. In this case the brakes should
be dried by pressing the brake pedal several times.
When the speed is over 80 km/h and the windscreen wipers are on, the
brake system moves the pads towards the brake discs for a few seconds.
This occurs - without the driver knowing - at regular intervals and allows a
faster response from the brakes when driving on wet roads.
The effectiveness of the brakes can also be temporarily reduced if the vehi-
cle is driven for some distance without using the brakes when there is a lot
of salt on the road in winter. In this case, the layer of salt on the brake discs
and pads has to wear off before braking.
Corrosion
There may be a tendency for corrosion to form on the discs and dirt to build
up on the brake pads if the vehicle is used infrequently or the brakes are
not used very often. If the brakes are not used frequently, or if rust has formed on the disks, it is
advisable to clean off the pads and disks by braking firmly a few times at a
moderately high speed
⇒
.
Faults in the brake system
If the brake pedal travel should ever increase suddenly, this may mean that
one of the two brake circuits has failed. Drive immediately to the nearest
specialised workshop and have the fault repaired. Drive there slowly and re-
member that you will have to apply more pressure on the brake pedal and
allow for longer stopping distances.
Low brake fluid level
Malfunctions can occur in the brake system if the brake fluid level is too
low. The brake fluid level is monitored electronically.
WARNING
When applying the brakes to clean off deposits on the pads and discs,
select a clear, dry road. Be sure not to inconvenience or endanger other
road users. Risk of accident.
CAUTION
● Never let the brakes “drag” by leaving your foot on the pedal when it is
not necessary to brake. This overheats the brakes, resulting in longer stop-
ping distances and greater wear.
● Before driving down a long, steep gradient, it is advisable to reduce
speed and change to a lower gear (or move the gear lever to a lower gear
position if your vehicle has automatic transmission). This makes use of en-
gine braking and prolongs the service life of the brakes. If you still have to
use the brakes, it is better to brake firmly at intervals than to apply the
brakes continuously.

189
Intelligent technology
Note
If you wish to equip the vehicle with accessories such as a front spoiler or
wheel covers, it is important that the flow of air to the front wheels is not
obstructed, otherwise the brakes can overheat.
Brake servo
The brake servo assists the driver when braking
The brake servo increases the pressure you apply to the brake pedal. The
brake servo works only when the engine is running.
WARNING
Ensure the vehicle does not move while in neutral, when the engine is
stopped. Failure to do so could result in an accident.
Note
If the brake servo is not working, e.g. because the vehicle has to be towed
or because it is broken, you will have to press the brake pedal considerably
harder to make up for the lack of servo assistance.
Power steering
Power steering makes it easier to turn the steering wheel
when the engine is running. Power steering assists the driver by reducing the force needed to turn the
steering wheel. Power steering does not work if the engine is off. In this case the steering
wheel requires much more force to turn.
If the steering is held at its
turning limit when the vehicle is stationary, this
will place an excessive load on the power steering system. Turning the
steering wheel to its limit places a load on the system, which causes noise.
It will also reduce the idling speed of the engine.
CAUTION
When the engine is running, do not turn the steering wheel to its limit for
more than 15 seconds. Otherwise, there is a risk of damaging the power
steering.
Note
● If the power steering should fail at any time or the engine is switched off
(for instance when being towed), the vehicle can still be steered. However,
more effort will be required to turn the steering wheel.
● If the system is leaking or malfunctioning, please take the vehicle to a
specialised workshop as soon as possible.
● The power steering system requires a special hydraulic fluid. The fluid
reservoir is located at the front of the engine compartment on the left
⇒ page 290. The correct fluid level in the reservoir is important for the pow-
er steering to function properly. The hydraulic fluid level is checked at the
Inspection Service.
Servotronic*
The servotronic system electronically adjusts the power as-
sisted steering.
In vehicles equipped with servotronic power steering the degree of power
assistance ⇒ page 189 is adjusted
electronically according to road speed.
Safety FirstOperating InstructionsPractical TipsTechnical Specifications

191
Driving and the environment
Driving and the environment
Running-in Running in a new engine
The engine needs to be run in over the first 1500 km.
Up to 1000 kilometres
– Do not drive at speeds of more than 2/3 the maximum speed.
– Do not accelerate hard.
– Avoid high engine revolutions.
– Do not tow a trailer.
From 1000 to 1500 kilometres
– Speeds can be gradually increased to the maximum road speed
or maximum permissible engine speed (rpm).
During its first few hours of running, the internal friction in the engine is
greater than later on, when all the moving parts have bedded in.
For the sake of the environment
If the engine is run in gently, its life will be increased and its oil consump-
tion reduced. Braking capacity and braking distance
The braking capacity and braking distance are influenced by
driving situations and road conditions.
The efficiency of the brakes depends directly on the
brake pad wear. The
rate of wear of the brake pads depends to a great extent on the conditions
under which the vehicle is operated and the way the vehicle is driven. If you
often drive in town traffic, drive short distances or have a sporty driving
style, we recommend that you have the thickness of your brake pads
checked by an Authorised Service Centre more frequently than recommen-
ded in the Service Plan.
If you drive with wet brakes, for example, after crossing areas of water, in
heavy rainfall or even after washing the vehicle, the effect of the brakes is
lessened as the brake discs are wet or even frozen (in winter). In this case
the brakes should be dried by pressing the brake pedal several times.
WARNING
Longer braking distances and faults in the brake system increase the risk
of accidents.
● New brake pads must be run in and do not have the correct friction
during the first 200 km. However, the reduced braking capacity may be
compensated by pressing on the brake pedal a little harder. This also ap-
plies when the brake pads have to be changed further on.
● If brakes are wet or frozen, or if you are driving on roads which have
been salted, braking power may be lower than normal.
Safety FirstOperating InstructionsPractical TipsTechnical Specifications

192Driving and the environment
WARNING (Continued)
● On steep slopes, if brakes are excessively used, they will overheat.
Before driving down a long steep slope, it is advisable to reduce speed
and change down into a lower gear or range (depending on the type of
transmission). This makes use of engine braking and relieves the brakes.
● Never let the brakes “drag” by applying light pressure. Continuous
braking will cause the brakes to overheat and the braking distance will
increase. Apply and then release the brakes alternately.
● Never let the vehicle run with the engine switched off. The braking
distance is increased considerably when the brake servo is not active.
● If the brake fluid loses its viscosity and is subjected to heavy use, va-
pour bubbles can form in the brake system. This reduces the efficiency of
the brakes.
● Non-standard or damaged front spoilers could restrict the airflow to
the brakes and cause them to overheat. Before purchasing accessories
please observe the relevant instructions ⇒ page 215, Technical modifi-
cations.
● If a brake circuit fails, the braking distance will be increased consider-
ably. Contact a specialised workshop immediately and avoid unnecessa-
ry journeys.
Exhaust gas purification system Catalytic converter*
To maintain the useful life of the catalytic converter
– Use only unleaded petrol with petrol engines, as lead damages
the catalytic converter.
– Do not let the fuel get too low in the tank. –
For engine oil changes, do not replenish with too much engine
oil ⇒ page 224.
– Never tow the vehicle to start it, use jump leads if necessary
⇒ page 280.
If you notice misfiring, uneven running or loss of power when the vehicle is
moving, reduce speed immediately and have the vehicle inspected at the
nearest specialised workshop. In general, the exhaust gas warning lamp
will light up when any of the described symptoms occur ⇒ page 66. If this
happens, unburnt fuel can enter the exhaust system and escape into the en-
vironment. The catalytic converter can also be damaged by overheating.
WARNING
The catalytic converter reaches very high temperatures! There is a risk of
fire.
● Never park where the catalytic converter could come into contact with
dry grass or flammable materials under the vehicle.
● Do not apply additional underseal or anti-corrosion coatings to the
exhaust pipes, catalytic converter or the heat shields on the exhaust sys-
tem. These materials could catch fire when the vehicle is being driven.
CAUTION
Never run the fuel tank completely dry because the irregularity of the fuel
supply may cause ignition problems. This allows unburnt fuel to enter the
exhaust system, which could cause overheating and damage the catalytic
converter.
For the sake of the environment
Even when the emission control system is working perfectly, there may be a
smell of sulphur from the exhaust gas under some conditions. This depends
on the sulphur content of the fuel used. Quite often the problem can be
solved by changing to another brand of fuel.

196Trailer towing
Trailer towing
Trailer towing
Technical requirements
The towing bracket must meet certain technical require-
ments.
Your vehicle is intended mainly for transporting passengers and luggage.
However, if suitably equipped, it can also be used to tow a trailer or cara-
van.
If your vehicle has been factory-supplied with a towing bracket, all of the
necessary technical and legal aspects for trailing towing have been taking
into account during manufacturing.
Your vehicle is fitted with a 13-pole socket for the electrical connection be-
tween the trailer and the vehicle. If the trailer has a 7-pole connector you
can use an adapter cable. This can be purchased at an Authorised Service.
If a towing bracket is to be fitted after the vehicle is purchased, this must be
done according to the instructions of the towing bracket manufacturer
⇒ page 204.
WARNING
If a towing bracket is retrofitted, the installation should be carried out by
a qualified workshop.
● Particularly in high outdoor temperatures, it is not possible to drive
up long steep gradients without a suitable cooling system. The engine
would heat up.
● Incorrect installation can result in a safety risk!
Notes on towing
There are a number of points which need to be checked be-
fore towing a trailer or caravan.
– Observe the maximum permitted trailer weights ⇒ page 290.
Trailer weight
Never exceed the maximum permitted trailer weight.
If you do not load the trailer up to the maximum permitted trailer weight,
you can then climb correspondingly steeper gradients.
The maximum trailer weights listed are only applicable for altitudes up to
1000 m above sea level. With increasing altitude the engine power and
therefore the vehicle's climbing ability are impaired because of the reduced
air density. The maximum trailer weight has to be reduced accordingly. The
weight of the vehicle and trailer must be reduced by about 10% for every
subsequent 1000 m (or part thereof). This figure refers to the combined
weight of the (loaded) vehicle and (loaded) trailer.
The figures for the drawbar load that appear on the identification plate of
the towing bracket are for certification purposes only. The correct figures for
your specific model, which may be lower than these figures for the towing
bracket, are given in the registration documents and on ⇒ page 283. Also
refer to ⇒ page 290.
Distributing the load
Distribute loads in the trailer so that heavy objects are as near to the axle as
possible. Loads carried in the trailer must be secured to prevent them mov-
ing.

197
Trailer towing
Where possible, operate the trailer with the maximum permitted drawbar
load on the ball joint of the towing bracket, but do not exceed the specified
limit.
Tyre pressure
Check the tyre pressures on your vehicle, and adjust for “full load” condi-
tions (refer to the sticker listing the tyre pressures on the door pillar). It may
also be necessary to adjust the tyre pressures on the trailer according to the
recommendations of the trailer manufacturer.
Exterior mirrors
Check whether you can see enough of the road behind the trailer with the
standard mirrors. If this is not the case you should have additional mirrors
fitted. The two exterior mirrors should be fitted on folding arms. Adjust the
mirrors to give sufficient rear vision.
Headlights
Before starting a journey, check the headlight beam settings with the trailer
hitched up. If necessary, alter the height of the headlight beams by means
of the headlight range control. See ⇒ page 119.
Power supply
When you remove the ignition key, the power supply to the trailer is inter-
rupted.
Removable ball joint coupling
Vehicles with a factory-fitted towing bracket are equipped with a removable
ball joint coupling. This is stored in the spare wheel well in the luggage
compartment together with the necessary fitting instructions.
Note
If you frequently tow, we recommend you also have the vehicle serviced be-
tween services. Notes on towing
Towing a trailer involves additional attention by the driver.
Weight distribution
The weight distribution of a loaded trailer with an unladen vehicle is very
unfavourable. However, if this cannot be avoided, drive extra slow to allow
for the unbalanced weight distribution.
Speed
The stability of the vehicle and trailer is reduced with increasing speed.
Therefore, it is advisable not to drive at the maximum permissible speed in
unfavourable road, weather or wind conditions. This especially applies
when driving downhill.
You should always reduce speed immediately if the trailer shows the slight-
est sign of swaying. Never try to stabilise the trailer by accelerating.
Anticipate hazards and brake in good time. If towing a trailer with an inertia
brake, first brake gently and then harder. This will prevent brake tapping by
the trailer wheels when they lock. Select a low gear in due course before go-
ing down a steep downhill. This enables you to use the engine braking to
slow down the vehicle.
Swaying and pitching can be reduced by stabiliser aids. We recommend
having stabiliser aids installed when towing trailers with a high trailer
weight. They can be purchased and installed at a Technical Service.
Reheating
When climbing long hills in hot weather with the engine running fast in low
gear, you should keep an eye on the coolant temperature gauge ⇒ page 60.
Reduce speed immediately if the needle moves to the right end of the scale.
If the temperature warning lamp in the instrument panel should start
flashing, stop the vehicle and let the engine cool down by running it at
idling speed for a few minutes.
Safety FirstOperating InstructionsPractical TipsTechnical Specifications