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Driving
CAUTION
● Please note that low obstacles detected by the system may no longer be
registered by the sensors as the car moves closer, so the system will not
give any further warning. Certain kinds of obstacles (such as wire fences,
chains, thin posts or trailer draw bars, high kerbs or painted railings etc)
may not always be detected by the system, so there is a risk of damaging
the vehicle in such cases.
● In some cases, obstacles with uniform edges and bumps may not be de-
tected immediately by the system due to their geometry. Take special care
of this type of obstacle (corners, rectangular objects, etc.), as they can
cause damage to the vehicle.
● Be especially careful when manoeuvring into a corner between two per-
pendicular walls. Carefully watch the approach of the wall to the side of the
vehicle (using the mirrors).
● The parking aid system does not replace use of the mirrors for manoeu-
vres.
● External ultra-sonic sources (pneumatic drills, construction machinery,
other vehicles with PDC) may interfere with the operation of the system.
● Periodic cleaning of the sensors, take care not to damage or scratch
them. When cleaning with high pressure washers or steam cleaners, the
sensors should be sprayed for only a very short period and from a distance
of more than 10 cm. Cruise speed* (Cruise control system)
Description
The cruise control system is able to maintain the set speed
in the range of 30 km/h to 180 km/h.
Once the speed setting has been saved, you may take your foot off the ac-
celerator.
WARNING
It could be dangerous to use the cruise control system if it is not possible
to drive at constant speed.
● Do not use the cruise control system when driving in dense traffic, on
roads with lots of bends or on roads with poor conditions (with ice, slip-
pery surfaces, loose grit or gravel), as this could cause an accident.
● Always switch the cruise control system off after using it in order to
avoid an involuntary use.
● It is dangerous to use a set speed which is too high for the current
road, traffic or weather conditions. Risk of accident.
Note
The cruise control cannot maintain a constant speed when descending
downhill. The vehicle will accelerate due to its own weight. Use the foot
brake to slow the vehicle.
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185
Driving
Adjusting set speed*
The speed can be altered without touching the accelerator or
the brake.
Fig. 151 Turn signal and
main beam headlight lev-
er: switch and rocker
switch for the cruise con-
trol
Setting a higher speed
– Press the upper part RES/+ of the rocker switch ⇒ fig. 151 A
to
increase the speed. The vehicle will continue to accelerate as
long as you keep the rocker switch pressed. When you release
the switch, the new speed is stored.
Setting a lower speed
– Press the lower part SET/– of the rocker switch A
to reduce the
speed. The vehicle will automatically reduce its speed for as
long as you keep the switch pressed. When you release the
switch, the new speed is stored.
When you increase speed with the accelerator and then release the pedal,
the system will automatically restore the set speed. This will not be the case, however, if the vehicle speed is more than 10 km/h higher than the
stored speed for longer than 5 minutes. The speed will have to be stored
again.
Cruise control is switched off if you reduce speed by depressing the brake
pedal. You can reactivate the control by pressing once on the upper part of
the rocker switch RES/+ ⇒ fig. 151
A
.
WARNING
It is dangerous to use a set speed which is too high for the current road,
traffic or weather conditions. Risk of accident.
Switching off the system temporarily*
Fig. 152 Turn signal and
main beam headlight lev-
er: switch and rocker
switch for the cruise con-
trol
The cruise control system will be switched off in the following situations:
● if the brake pedal is depressed,
● if the clutch pedal is depressed,
Safety FirstOperating InstructionsPractical TipsTechnical Specifications
186Driving
● if the vehicle is accelerated to over 180 km/h,
● when the lever B
is moved to the position “CANCEL” without reaching
the “OFF” position. Once the “CANCEL” operation is completed, the lever is
released and returns to its initial position.
To resume the cruise control, release the brake or clutch pedal or reduce the
vehicle speed to less than 180 km/h and press once on the upper part of
the rocker switch RES/+ ⇒ fig. 152 A
.
WARNING
It is dangerous to use a set speed which is too high for the current road,
traffic or weather conditions. Risk of accident.
Complete system deactivation*
Fig. 153 Turn signal and
main beam headlight lev-
er: switch and rocker
switch for the cruise con-
trol Vehicles with a manual gearbox
The system is completely turned off
by moving the control B
all the way to
the right hand side (OFF engaged), or when the vehicle is stationary, igni-
tion off.
Vehicles with automatic gearbox / DSG automatic gearbox*
To completely disengage the system, the selector lever must be placed in
one of the following positions: P, N, R or 1 or with the vehicle stopped and
the ignition turned off.
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Practical Tips Intelligent technology
Brakes Brake servo
The brake servo increases the pressure you apply to the brake pedal. It
works only when the engine is running .
If the brake servo is not functioning due to a malfunction, or if the vehicle
has to be towed, you will have to press the brake pedal considerably harder
to make up for the lack of servo assistance.
WARNING
The braking distance can also be affected by external factors.
● Never let the vehicle coast with the engine switched off. Failure to do
so could result in an accident. The braking distance is increased consid-
erably when the brake servo is not active.
● If the brake servo is not working, for example when the vehicle is be-
ing towed, you will have to press the brake pedal considerably harder
than normal.
Hydraulic Brake Assist (HBA)*
The Hydraulic Brake Assist function (HBA) is only included in
vehicles with ESC (ESP).
In an emergency, most drivers brake in time, but not with maximum force.
This results in unnecessarily long braking distances.
This is when the brake assist system comes into action. When pressing the
brake pedal rapidly, the assistant interprets it as an emergency. It then very
quickly builds up the full brake pressure so that the ABS can be activated
more quickly and efficiently, thus reducing the braking distance.
Do not reduce the pressure on the brake pedal. The brake assist system
switches off automatically as soon as you release the brake.
Emergency braking warning
If the vehicle is braked suddenly and continuously at a speed of more than
80 km/h, the brake light flashes several times per second to warn vehicles
driving behind. If you continue braking, the hazard warning lights will come
on automatically when the vehicle comes to a standstill. They switch off au-
tomatically when the vehicle starts to move again.
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188Intelligent technology
WARNING
● The risk of accident is higher if you drive too fast, if you do not keep
your distance to the vehicle in front, and when the road surface is slip-
pery or wet. The increased accident risk cannot be reduced by the brake
assist system.
● The brake assist system cannot defy the laws of physics. Slippery
and wet roads are dangerous even with the brake assist system! There-
fore, it is essential that you adjust your speed to suit the road and traffic
conditions. Do not let the extra safety features tempt you into taking any
risks when driving.
Anti-lock brake system and traction control
M-ABS (ABS and ASR (TCS))
Anti-lock brake system (ABS)
The anti-lock brake system prevents the wheels locking dur-
ing braking. The anti-lock brake system (ABS) is an important part of the vehicle's active
safety system.
How the ABS works
If one of the wheels is turns too slowly in relation to the road speed, and is
close to locking, the system will reduce the braking pressure for this wheel.
The driver is made aware of this control process by a pulsating of the brake
pedal and audible noise. This is a deliberate warning to the driver that one
or more of the wheels is tending to lock and the ABS control function has
intervened. In this situation it is important to keep the brake pedal fully de-
pressed so the ABS can regulate the brake application. Do not “pump”. If you brake hard on a slippery road surface, the best possible control is re-
tained as the wheels do not lock.
However, ABS will not necessarily guarantee shorter braking distances in
all
conditions. The braking distance could even be longer if you brake on gravel
or on fresh snow covering a slippery surface.
WARNING
● The anti-lock brake system cannot defy the laws of physics. Slippery
and wet roads are dangerous even with ABS! If you notice that the ABS is
working (to counteract locked wheels under braking), you should reduce
speed immediately to suit the road and traffic conditions. Do not let the
extra safety features tempt you into taking any risks when driving.
● The effectiveness of ABS is also determined by the tyres fitted
⇒ page 236.
● If the running gear or brakes are modified, the effectiveness of the
ABS could be severely limited.
Traction control system ASR (TCS)
The traction control system prevents the drive wheels from
spinning when the vehicle is accelerating. Description and operation of the traction control system during
acceleration ASR (TCS)
ASR (TCS) reduces engine power to help prevent the drive wheels of front-
wheel drive vehicles losing traction during acceleration. The system works
in the entire speed range in conjunction with ABS. If a malfunction should
occur in the ABS, the ASR (TCS) will also stop working.
The ASR (TCS) helps the vehicle to start moving, accelerate and climb a gra-
dient in slippery conditions where this may otherwise be difficult or even
impossible.
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Intelligent technology
The ASR (TCS) is connected automatically when the engine starts. If neces-
sary, it may be turned on or off pushing the button on the centre console.
When the ASR (TCS) is disconnected, the warning lamp
OFF
lights up. The
TCS should normally be left on. Only in exceptional circumstances, when the
slipping of the wheels is required, should it be disconnected, for example
● With compact temporary spare wheel.
● When using the snow chains.
● When driving in deep snow or on loose surfaces
● When the vehicle is bogged-down, to free it by rocking.
The TCS should be switched on again as soon as possible.
WARNING
● Remember that the ASR (TCS) cannot defy the laws of physics. This
should be kept in mind, particularly on slippery and wet roads and when
towing a trailer.
● Always adapt your driving style to suit the condition of the roads and
the traffic situation. Do not let the extra safety afforded by ASR (TCS)
tempt you into taking any risks when driving.
CAUTION
● To ensure that the ASR (TCS) functions correctly, all four wheels must be
fitted with the same tyres. Any differences in the rolling radius of the tyres
can cause the system to reduce engine power when this is not desired.
● Modifications to the vehicle (e.g. to the engine, the brake system, run-
ning gear or any components affecting the wheels and tyres) could affect
the efficiency of the ABS and ASR (TCS). XDS*
Driveshaft differential
When taking a bend, the driveshaft differential mechanism allows the outer
wheel to turn at a higher speed than the inner wheel. In this way, the wheel
that is turning faster (outer wheel) receives less drive torque than the inner
wheel. This may mean that in certain situations the torque delivered to the
inner wheel is too high, causing the wheels to spin. On the other hand, the
outer wheel is receiving a lower drive torque than it could transmit. This
causes an overall loss of lateral grip on the front axle, resulting in under-
steer or “lengthening” of the trajectory.
By using the ESC (ESP) sensors and signals, the XDS system is able to de-
tect and correct this effect.
Through the ESC (ESP), the XDS brakes the inner wheel, thereby counteract-
ing the excess drive torque in this wheel. This means that the driver's de-
sired trajectory is much more precise,
The XDS system operates in combination with the ESC (ESP) and is always
active, even when the traction control ASR (TCS) is disconnected.
Electronic Stability Control ESC (ESP) *
General notes
The Electronic Stability Control increases the vehicle's stabil-
ity on the road. The Electronic Stability Control helps reduce the danger of skidding.
The Electronic Stability Control ESC (ESP) includes the ABS, EDL, ASR (TCS)
and Steering manoeuvre recommendations.
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190Intelligent technology
Electronic Stability Control ESC* (ESP)
The ESC (ESP) reduces the danger of skidding by braking the wheels indi-
vidually.
The system uses the steering wheel angle and road speed to calculate the
changes of direction desired by the driver, and constantly compares them
with the actual behaviour of the vehicle. If the desired course is not being
maintained (for instance, if the vehicle is starting to skid), then the ESC
(ESP) compensates automatically by braking the appropriate wheel.
The forces acting on the braked wheel bring the vehicle back to a stable
condition. If the vehicle tends to oversteer, the system will act on the front
wheel on the outside of the turn.
Steering manoeuvre recommendations
This is a complementary safety function included in the ESC (ESP). This
function aids the driver to better stabilize the vehicle in a critical situation.
For example, in case of sudden braking surface with varied adherence, the
vehicle will tend to destabilise its trajectory to the right or to the left. In this
case the ESC (ESP) recognises the situation and helps the driver with a
counter steering manoeuvre from the power steering.
This function simply provides the driver with a recommended manoeuvre in
critical situations.
The vehicle does not steer itself with this function, the driver has full control
of the vehicle at all times.
WARNING
● Remember that ESC (ESP) cannot defy the laws of physics. This
should be kept in mind, particularly on slippery and wet roads and when
towing a trailer.
● Always adapt your driving style to suit the condition of the roads and
the traffic situation. Do not let the extra safety afforded by ESC (ESP)
tempt you into taking any risks when driving.
CAUTION
● To ensure that the ESC (ESP) functions correctly, all four wheels must be
fitted with the same tyres. Any differences in the rolling radius of the tyres
can cause the system to reduce engine power when this is not desired.
● Modifications to the vehicle (e.g. to the engine, the brake system, run-
ning gear or any components affecting the wheels and tyres) could affect
the efficiency of the ABS, EDL, ESC (ESP) and ASR (TCS).
Anti-lock brake system (ABS)
The anti-lock brake system prevents the wheels locking during braking
⇒ page 188.
Electronic differential lock (EDL)*
The electronic differential lock helps prevent the loss of trac-
tion caused if one of the driven wheels starts spinning.
EDL helps the vehicle to start moving, accelerate and climb a gradient in
slippery conditions where this may otherwise be difficult or even impossi-
ble.
The system will control the revolutions of the drive wheels using the ABS
sensors (in case of an EDL fault the warning lamp for ABS lights up)
⇒ page 82.
At speeds of up to approximately 80 km/h, it is able to balance out differen-
ces in the speed of the driven wheels of approximately 100 rpm caused by a
slippery road surface on one side of the vehicle. It does this by braking the
wheel which has lost traction and distributing more driving force to the oth-
er driven wheel via the differential.
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Intelligent technology
To prevent the disc brake of the braking wheel from overheating, the EDL
cuts out automatically if subjected to excessive loads. The vehicle will con-
tinue to function normally without EDL. For this reason, the driver is not in-
formed that the EDL has been switched off.
The EDL will switch on again automatically when the brake has cooled
down.
WARNING
● When accelerating on a slippery surface, for example on ice and
snow, press the accelerator carefully. Despite EDL, the driven wheels may
start to spin. This could impair the vehicle's stability.
● Always adapt your driving style to suit road conditions and the traffic
situation. Do not let the extra safety afforded by EDL tempt you into tak-
ing any risks when driving, this can cause accidents.
CAUTION
Modifications to the vehicle (e.g. to the engine, the brake system, running
gear or any components affecting the wheels and tyres) could affect the effi-
ciency of the EDL ⇒ page 214.
Traction control system ASR (TCS)
The traction control system prevents the drive wheels from spinning when
the vehicle is accelerating ⇒ page 188. All-wheel drive*
On all-wheel drive models, the engine power is distributed
to all four wheels
General notes
The all-wheel drive system operates completely automatically. The propul-
sion force is distributed among the four wheels and adapted to the driving
style and the road conditions.
The all-wheel drive is specially designed to complement the superior engine
power. This combination gives the vehicle exceptional handling and per-
formance capabilities, both on normal roads and in more difficult condi-
tions, such as snow and ice.
Winter tyres
Thanks to its all-wheel drive, your vehicle will have plenty of traction in win-
ter conditions, even with the standard tyres. Nevertheless, we still recom-
mend that winter tyres or all-season tyres should be fitted on all four wheels
when winter road conditions are expected, mainly because this will give a
better braking response.
Snow chains
On roads where snow chains are mandatory, this also applies to cars with
all-wheel drive.
Changing tyres
On vehicles with all-wheel drive, all four tyres must have the same rolling
circumference ⇒ page 241.
Safety FirstOperating InstructionsPractical TipsTechnical Specifications