
X
To activate/deactivate: press button;.
If indicator lamp :is lit, operation of the
rear side windows is disabled. Operation is
only possible using the switches in the
driver's door. If indicator lamp :is off,
operation is possible using the switches in
the rear compartment. Driving safety systems
Overview of driving safety systems
In this section, you will find information about
the following driving safety systems:
R ABS ( Anti-lock BrakingSystem)
(Y page 67)
R BAS ( Brake Assist System) (Y page 68)
R BAS PLUS ( BrakeAssist System PLUS) with
Cross-Traffic Assist (Y page 68)
R COLLISION PREVENTION ASSIST (distance
warning function and adaptive Brake
Assist) (Y page 70)
R ESP ®
(Electronic StabilityProgram)
(Y page 72)
R EBD ( Electronic Brake force Distribution)
(Y page 75)
R ADAPTIVE BRAKE (Y page 75)
R PRE-SAFE ®
Brake (Y page 76) Important safety notes
If you fail to adapt your driving style or
become distracted, the driving safety
systems can neither reduce the risk of
accident nor override the laws of physics.
Driving safety systems are merely aids
designed to assist driving. You are
responsible for the distance to the vehicle in
front, for vehicle speed and for braking in
good time. Always adapt your driving style to
suit the prevailing road, weather and traffic
conditions and maintain a safe distance from
the vehicle in front. Drive carefully. i
The driving safety systems described only
work as effectively as possible when there
is adequate contact between the tires and
the road surface. Please pay special
attention to the notes on tires,
recommended minimum tire tread depths,
etc. (Y page 372).
In wintry driving conditions, always use
winter tires (M+S tires) and if necessary,
snow chains. Only in this way will the
driving safety systems described in this
section work as effectively as possible. ABS (Anti-lock Braking System)
General information ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the
vehicle when braking.
The yellow
!ABS warning lamp in the
instrument cluster lights up when the ignition
is switched on. It goes out when the engine is
running.
Important safety notes i
Observe the "Important safety notes"
section ( Ypage 67). G
WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking
characteristics may be severely impaired.
Additionally, further driving safety systems
are deactivated. There is an increased danger
of skidding and accidents.
Drive on carefully. Have ABS checked
immediately at a qualified specialist
workshop.
When ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp ( Ypage 288) and
display messages which may be shown in the
instrument cluster (Y page 258). Driving safety systems
67Safety Z
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automatically increase the braking force to a
level suitable for the traffic conditions.
X Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if:
R you release the brake pedal
R there is no longer any danger of a rear-end
collision
R no obstacle is detected in front of your
vehicle
Adaptive Brake Assist is then deactivated.
Up to vehicle speeds of around 155 mph
(250 km/h), adaptive Brake Assist is capable
of reacting to moving objects that have
already been recognized as such at least once
over the period of observation. Adaptive
Brake Assist does not react to stationary
obstacles.
If Adaptive Brake Assist is not available due
to a malfunction in the radar sensor system,
the brake system remains available with full
brake boosting effect and BAS.
In particular, the detection of obstacles can
be impaired if there is:
R dirt on the sensors or anything else
covering the sensors
R snow or heavy rain
R interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the
vehicle, have the configuration and operation
of the radar sensor checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle. ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes"
section (Y page 67).
ESP ®
monitors driving stability and traction,
i.e. power transmission between the tires and
the road surface.
If ESP ®
detects that the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilize the
vehicle. The engine output is also modified to
keep the vehicle on the desired course within
physical limits. ESP ®
assists the driver when
pulling away on wet or slippery roads. ESP ®
can also stabilize the vehicle during braking.
ETS/4ETS (Electronic Traction System) ETS/4ETS traction control is part of ESP
®
.
Traction control brakes the drive wheels
individually if they spin. This enables you to
pull away and accelerate on slippery surfaces,
for example if the road surface is slippery on
one side. In addition, more drive torque is
transferred to the wheel or wheels with
traction.
Traction control remains active, even if you
deactivate ESP ®
.
Important safety notes i
Observe the "Important safety notes"
section (Y page 67). G
WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilize the vehicle. Additionally, further
driving safety systems are deactivated. This
increases the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
! Vehicles with 4MATIC: switch off the
ignition when the parking brake is being
tested on a brake dynamometer. 72
Driving safety systemsSafety
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X
To activate ESP ®
:briefly press button :.
The å ESP®
OFF warning lamp in the
instrument cluster goes out. The ÷ONON
message appears in the multifunction
display.
Characteristics of activated SPORT
handling mode
If SPORT handling mode is activated and one
or more wheels start to spin, the ÷ESP®
warning lamp in the instrument cluster
flashes. ESP ®
only stabilizes the vehicle to a
limited degree.
When SPORT handling mode is activated:
R ESP ®
only improves driving stability to a
limited degree.
R traction control is still activated.
R engine torque is only restricted to a limited
degree, and the drive wheels are able to
spin.
The spinning of the wheels results in a
cutting action for better traction on loose
surfaces.
R ESP ®
still provides support when you
brake.
Characteristics when ESP ®
is deactivated
If ESP ®
is deactivated and one or more wheels
start to spin, the ÷ESP®
warning lamp in
the instrument cluster does not flash. In such
situations, ESP ®
will not stabilize the vehicle.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R engine torque is restricted to a limited
degree and the drive wheels are able to
spin.
The spinning of the wheels results in a
cutting action for better traction on loose
surfaces.
R traction control is still activated.
R PRE-SAFE ®
is no longer available, nor is it
activated if you brake firmly and ESP ®
intervenes. R
PRE-SAFE ®
Brake is no longer available, it
is also not activated if you brake firmly and
ESP ®
intervenes.
R ESP ®
still provides support when you
brake. EBD (electronic brake force
distribution)
General information EBD monitors and controls the brake
pressure on the rear wheels to improve
driving stability while braking.
Important safety notes
i
Observe the "Important safety notes"
section for driving safety systems
(Y page 67). G
WARNING
If EBD has malfunctioned, the rear wheels can
still lock, e.g. under full braking. This
increases the risk of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Have
the brake system checked at a qualified
specialist workshop.
Observe information regarding indicator and
warning lamps (Y page 288) as well as
display messages (Y page 260). ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In
addition to the braking function, ADAPTIVE
BRAKE also has the HOLD function
(Y page 202) and hill start assist
(Y page 162). Driving safety systems
75Safety Z
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If you do not open the vehicle within
approximately 40 seconds of unlocking:
R
the vehicle is locked again.
R the theft deterrent locking system is
armed again.
X To lock centrally: press the&button.
The SmartKey centrally locks/unlocks:
R the doors
R the trunk lid/tailgate
R the fuel filler flap
The turn signals flash once when unlocking
and three times when locking.
You can also set an audible signal to confirm
that the vehicle has been locked. The audible
signal can be activated and deactivated using
the on-board computer (Y page 252).
When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer (Y page 251). KEYLESS-GO
General notes Bear in mind that the engine can be started
by any of the vehicle occupants if there is a
KEYLESS-GO key in the vehicle.
Locking/unlocking centrally
You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry
the SmartKey with you. You can combine the
functions of KEYLESS-GO with those of a
conventional SmartKey. Unlock the vehicle
by using KEYLESS-GO, for instance, and lock
it using the
&button on the SmartKey.
When locking or unlocking with KEYLESS-GO,
the distance between the SmartKey and the
corresponding door handle must not be
greater than 3 ft (1 m). A check which periodically establishes a radio
connection between the vehicle and the
SmartKey determines whether a valid
SmartKey is in the vehicle. This occurs, for
example:
R
when the external door handles are
touched
R when starting the engine
R while the vehicle is in motion X
To unlock the vehicle: touch the inner
surface of the door handle.
X To lock the vehicle: touch sensor
surface :.
X Convenience closing feature: touch
recessed sensor surface ;for an
extended period.
Further information on the convenience
closing feature (Y page 99).
X To unlock the trunk lid/tailgate: pull the
handle on the trunk lid/tailgate.
The vehicle only unlocks the trunk lid/
tailgate. Changing the settings of the locking
system
You can change the settings of the locking
system. This means that only the driver's door
and the fuel filler flap are unlocked when the
vehicle is unlocked. This is useful if you
frequently travel on your own.
X To change the setting: press and hold
down the %and& buttons on the
SmartKey simultaneously for SmartKey
83Opening and closing Z
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Problem Possible causes/consequences and
M
MSolutions You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. The engine cannot be
started using the
SmartKey. The on-board voltage is too low.
X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 360).
or
X Jump-start the vehicle (Y page 362).
or
X Consult a qualified specialist workshop. The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. The vehicle is locked.
X
Unlock the vehicle and try to start the vehicle again. There is interference from a powerful source of radio waves.
X
Start your vehicle with the SmartKey in the ignition lock. Doors
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the vehicle. Always keep the SmartKey out of
reach of children.
G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
Ideally, place luggage or loads in the trunk/
cargo compartment. Observe the loading
guidelines (Y page 298). Unlocking and opening doors from
the inside
You can open a door from inside the vehicle
even if it has been locked. If the vehicle has
been locked with the SmartKey or with
KEYLESS-GO, opening a door from the inside 88
DoorsOpening and closing
ProCarManuals.com

The vehicle is locked automatically when the
ignition is switched on and the wheels are
turning.
You could therefore lock yourself out if:
R the vehicle is being pushed.
R the vehicle is being towed.
R the vehicle is on a roller dynamometer.
You can also switch the automatic locking
function on and off using the on-board
computer (Y page 251). Unlocking the driver's door
(mechanical key)
If the vehicle can no longer be unlocked with
the SmartKey, use the mechanical key.
X Take the mechanical key out of the
SmartKey (Y page 84).
X Insert the mechanical key into the lock of
the driver's door as far as it will go. 1
To unlock
X Turn the mechanical key counter-clockwise
to position 1.
The door is unlocked.
X Turn the mechanical key back and remove
it.
X Insert the mechanical key into the
SmartKey.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm
system will be triggered (Y page 78). Locking the vehicle (mechanical key)
If the vehicle can no longer be locked with the
SmartKey, use the mechanical key.
X Open the driver's door.
X Close the front-passenger door, the rear
doors and the trunk lid/tailgate.
X Press the locking button (Y page 89).
X Check whether the locking knobs on the
front-passenger door and the rear doors
are still visible. Press down the locking
knobs manually, if necessary ( Ypage 88).
X Close the driver's door.
X Take the mechanical key out of the
SmartKey (Y page 84).
X Insert the mechanical key into the lock of
the driver's door as far as it will go. 1
To lock
X Turn the mechanical key clockwise as far
as it will go to position 1.
X Turn the mechanical key back and remove
it.
X Make sure that the doors and the trunk lid/
tailgate are locked.
X Insert the mechanical key into the
SmartKey. Trunk/cargo compartment
Important safety notes
G
WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Exhaust 90
Trunk/cargo compartmentOpening and closing
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Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: (Y page 26).Correct driver's seat position
G
WARNING
You could lose control of your vehicle if you
do the following while driving:
R adjust the driver's seat, head restraint,
steering wheel or mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint,
steering wheel and mirror and fasten your
seat belt before starting the engine. X
Observe the safety guidelines on seat
adjustment (Y page 109).
X Make sure that seat =is adjusted
properly.
Electrical seat adjustment (Y page 110)
When adjusting the seat, make sure that:
R you are as far away from the driver's air bag
as possible.
R you are sitting in a normal upright position.
R you can fasten the seat belt properly.
R you have moved the backrest to an almost
vertical position.
R you have set the seat cushion angle so that
your thighs are gently supported.
R you can depress the pedals properly.
X Check whether the head restraint is
adjusted properly.
When doing so, make sure that you have
adjusted the head restraint so that the back
of your head is supported at eye level by
the center of the head restraint.
X Observe the safety guidelines on steering
wheel adjustment (Y page 119).
X Make sure that steering wheel :is
adjusted properly.
Adjusting the steering wheel electrically
(Y page 119)
When adjusting the steering wheel, make
sure that:
R you can hold the steering wheel with your
arms slightly bent.
R you can move your legs freely.
R you can see all the displays in the
instrument cluster clearly.
X Observe the safety guidelines for seat belts
(Y page 55).
X Check whether you have fastened seat
belt ;properly (Y page 56).108
Correct driver's seat positionSeats, steering wheel and mirrors
ProCarManuals.com

Problems with the windshield wipers
Problem Possible causes/consequences and
M
MSolutions The windshield wipers
are jammed. Leaves or snow, for example, may be obstructing the windshield
wiper movement. The wiper motor has been deactivated.
X
For safety reasons, you should remove the SmartKey from the
ignition lock.
or
X Switch off the engine using the Start/Stop button and open the
driver's door.
X Remove the cause of the obstruction.
X Switch the windshield wipers back on. The windshield wipers
fail completely. The windshield wiper drive is malfunctioning.
X
Select another wiper speed on the combination switch.
X Have the windshield wipers checked at a qualified specialist
workshop. 142
Windshield wipersLights and windshield wipers
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