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● 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 (20 mph) to 180 km/h (110 mph). 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.
WARNING (Continued)
● Always switch the cruise control system off after using it in order to
avoid 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.
Switching the cruise control system on and off
Fig. 148 Turn signal and
main beam headlight lev-
er: switch and rocker
switch for the cruise con-
trol
Switching on the cruise control system
– Push the switch ⇒
Fig. 148 B
to the left to
ON
.
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184Driving
Switching off the cruise control system
–Either push the switch B
to the right to
OFF or turn the ignition
off when the vehicle is stationary.
When the cruise control is on and a speed is programmed, the indicator
on the instrument panel is lit. 1)
If the cruise control system is switched off, the symbol is switched off.
The system will also be deactivated completely when 1st gear is selected.*
Setting speed*
Fig. 149 Turn signal and
main beam headlight lev-
er: switch and rocker
switch for the cruise con-
trol
– Press the lower part SET/- of the rocker switch ⇒ Fig. 149 A
once briefly when you have reached the speed you wish to set. When you release the rocker switch, the current speed is set and held con-
stant.
Adjusting set speed*
The speed can be altered without touching the accelerator or
the brake.
Fig. 150 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. 150 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.
1)
Depending on the version of the model.
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Driving
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 (mph) higher than
the stored speed for longer than 5 minutes. The speed will have to be stor-
ed 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. 150 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 cruise control temporarily*
Fig. 151 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,
● if the vehicle is accelerated to over 180 km/h (110 mph),
● 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 (110 mph) and press once on the up-
per 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.
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186Driving
Complete system deactivation*
Fig. 152 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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Intelligent technology
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 function (Hydraulic Brake Assist HBA) is only included in
vehicles with ESC.
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 (50 mph), 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 automatically when the vehicle starts to move again.
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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 and traction control systems
M-ABS (ABS and ASR) 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 239.
● If the running gear or brake system is modified, the effectiveness of
the ABS could be severely limited.
Drive wheel traction control system (ASR)
The traction control system prevents the driven wheels from
spinning when the vehicle is accelerating. Description and operation of the traction control system during
acceleration (ASR
On front-wheel drive vehicles, the ASR system intervenes, reducing engine
power and preventing the driven wheels from slipping during acceleration.
The system works in the entire speed range in conjunction with ABS. If a
failure occurs in the ABS, the ASR will also stop working.
The ASR helps the car to start moving, accelerate and climb a gradient in
slippery conditions, where this may otherwise be difficult or even impossi-
ble.
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The ASR automatically switches on when the engine is started. If necessary,
it may be turned on or off pushing the button on the centre console.
When the ASR is switched off, the
OFF
warning lamp will light up. The ASR
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 ASR should be switched on again as soon as possible.
WARNING
● Remember that not even the ASR can 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. The greater safety provided by the ASR should not
encourage you to run any risks.
CAUTION
● To ensure that the ASR works correctly, identical tyres should be fitted
on all four wheels. Any differences in the rolling radius of the tyres can
cause the system to reduce engine power when this is not desired.
● Any modifications made to the vehicle (for example, to the engine,
brake system, running gear or to the combination of wheels and tyres) may
affect the operation of the ABS and ASR. 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 sensors and signals, the XDS system is able to detect and
correct this effect.
Via the ESC, the XDS will brake the inside wheel and counter the excess
driving torque of that wheel. This means that the driver's desired trajectory
is much more precise,
The XDS system works in combination with the ESC and is always active,
even when the ASR traction control is disconnected.
Electronic Stability Control (ESC)*
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) includes the ABS, EDL, ASR and Steer-
ing manoeuvre recommendation systems.
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190Intelligent technology
Electronic Stability Control (ESC*)
The ESC reduces the risk of skidding by braking the wheels individually.
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. When irregularities occur, for exam-
ple, if the vehicle begins to skid, the ESC brakes the appropriate wheel au-
tomatically.
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. This function
aids the driver to better stabilize the vehicle in a critical situation. For exam-
ple, 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 recognises the situation and assists the driver with a counter steer-
ing 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 not even the ESC can 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. The greater safety provided by the ESC should not
encourage you to run any risks.
CAUTION
● To ensure that the ESC works 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.
● Any modifications made to the vehicle (for example, to the engine,
brake system, running gear or to the combination of wheels and tyres) may
affect the operation of the ABS, EDL, ESC and ASR.
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 driven 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.