
Function
The distance warning function issues a warn-
ing at speeds:
R of approximately 30 km/h or more, if, over
several seconds, the distance maintained
to the vehicle travelling in front is insuffi-
cient. The ·distance warning lamp
then lights up in the instrument cluster.
R of approximately 7 km/h or more, if you
rapidly approach a vehicle in front. An inter-
mittent warning tone will then sound, and
the · distance warning lamp will light
up in the instrument cluster.
X Brake immediately in order to increase the
distance from the vehicle in front.
or
X Take evasive action provided it is safe to do
so.
Due to the nature of the system, particularly
complicated but non-critical driving condi-
tions may also cause the system to display a
warning.
With the help of the radar sensor system, the distance warning function can detect obsta-
cles that are in the path of your vehicle for an
extended period of time.
Up to a speed of approximately 70 km/h, the
distance warning function can also react to
stationary obstacles, such as stopped or
parked vehicles.
Autonomous braking function If the driver does not react to the distance
warning signal in a critical situation, COLLI-
SION PREVENTION ASSIST PLUS can assist
with the autonomous braking function.
The autonomous braking function:
R gives the driver more time to react to criti-
cal driving situations
R can help the driver to avoid an accident or
R reduces the effects of an accident Vehicles without DISTRONIC PLUS:
the
autonomous braking function is available in
the following speed ranges:
R 7 - 105 km/h for moving objects
R 7 - 50 km/h for stationary objects
Vehicles with DISTRONIC PLUS: the auton-
omous braking function is available in the fol- lowing speed ranges:
R 7 - 200 km/h for moving objects
R 7 - 50 km/h for stationary objects
Due to the nature of the system, complicated
but non-critical driving conditions may also
cause the Autonomous Braking function to
intervene.
If the autonomous braking function demands particularly high braking force, preventative
passenger protection measures (PRE-SAFE ®
)
are activated simultaneously (Y page 63).
Adaptive Brake Assist General notes
i Observe the "Important safety notes" sec-
tion (Y page 78).
With the help of Adaptive Brake Assist, the
distance warning signal can detect obstacles
that are in the path of your vehicle for an
extended period of time.
If Adaptive Brake Assist detects a risk of a
collision with the vehicle in front, it calculates
the braking force necessary to avoid a colli-
sion. If you apply the brakes forcefully, Adap-
tive Brake Assist will automatically increase
the braking force to a level suitable for the
traffic conditions.
Adaptive Brake Assist provides braking assis- tance in hazardous situations at speeds
above 7 km/h. It uses radar sensor technol-
ogy to assess the traffic situation.
Up to a speed of approximately 250 km/h,
Adaptive Brake Assist is capable of reacting
to moving objects that have already been
detected as such at least once over the period
of observation. Driving safety systems
83Safety Z

Up to a speed of approximately 70 km/h,
Adaptive Brake Assist reacts to stationary
obstacles.
If the autonomous braking function demands particularly high braking force, preventative
passenger protection measures (PRE-SAFE ®
)
are activated simultaneously (Y page 63). On
vehicles with the Driving Assistance package,
preventive passenger protection measures
(PRE-SAFE ®
PLUS) are triggered (Y page 64).
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 collision
R no obstacle is detected in front of your
vehicle
Adaptive Brake Assist is then deactivated.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 78).G
WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist can:
R intervene unnecessarily
R not intervene
There is a risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake. Terminate the
intervention in a non-critical driving situation. G
WARNING
Adaptive Brake Assist does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering As a result, the Adaptive Brake Assist may not
intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake.
Due to the nature of the system, particularly
complicated but non-critical driving condi-
tions may also cause Brake Assist to inter-
vene.
If Adaptive Brake Assist is not available due to a malfunction in the radar sensor system, thebrake system remains available with full
brake boosting effect and BAS. Adaptive brake lights
The adaptive brake lights warn following traf- fic in an emergency braking situation:
R by flashing brake lamps
R by activating the hazard warning lamps
If you brake sharply from a speed of more
than 50 km/h or if braking is assisted by BAS
or BAS PLUS, the brake lamps flash rapidly. In this way, traffic travelling behind you is
warned in an even more noticeable manner.
If you brake sharply from a speed of more
than 70 km/h to a standstill, the hazard warn-
ing lamps are activated automatically. If the
brakes are applied again, the brake lamps
light up continuously. The hazard warning
lamps switch off automatically if you travel
faster than 10 km/h. You can also switch off
the hazard warning lamps using the hazard
warning button (Y page 141). ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes" sec-
tion (Y page 78).
ESP ®
monitors driving stability and traction,
i.e. power transmission between the tyres
and the road surface. 84
Driving safety systemsSafety

tip over before ESP
®
can detect this. There is
a risk of an accident.
Always adapt your driving style to the prevail- ing road and weather conditions.
If your vehicle/trailer combination begins to
lurch, you can only stabilise the vehicle/
trailer combination by depressing the brake
firmly.
ESP ®
trailer stabilisation is active above
speeds of approximately 65 km/h.
ESP ®
trailer stabilisation does not work if
ESP ®
is deactivated or disabled because of a
malfunction.
Crosswind Assist General notes
Strong crosswind gusts can impair the road-
holding of your vehicle when driving straight
ahead. The crosswind driving assistance
function integrated in ESP ®
noticeably
reduces these impairments.
Depending on the direction and intensity of
the side wind, ESP ®
is activated automati-
cally.
ESP ®
intervenes with stabilising braking to
assist you in keeping the vehicle in the lane.
Crosswind Assist is active at vehicle speeds
above 80 km/h when driving straight ahead
or cornering gently.
Important safety notes
Crosswind Assist does not work if ESP ®
is
deactivated or disabled because of a mal-
function. EBD (electronic brake force distribu-
tion)
General notes EBD monitors and controls the brake pres-
sure on the rear wheels to improve driving
stability while braking. Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 78). G
WARNING
If EBD is malfunctioning, the rear wheels can
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 spe-
cialist workshop.
Observe information regarding indicator and
warning lamps (Y page 379) as well as dis-
play messages (Y page 339). ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In addi- tion to the braking function, ADAPTIVE BRAKE
also has the HOLD function (Y page 247)and
hill start assist (Y page 191). PRE-SAFE
®
Brake
General notes PRE-SAFE
®
Brake can help you to minimise
the risk of a collision with a vehicle ahead or a pedestrian, and reduce the effects of such a
collision. If PRE-SAFE ®
Brake has detected a
risk of a collision, you will be warned visually
and acoustically as well as by automatic brak- ing.
i Pay attention to the important safety
notes in the "Driving safety systems" sec-
tion (Y page 78).
PRE‑SAFE ®
Brake is only available in vehicles
with the Driving Assistance Plus package.
For PRE-SAFE ®
Brake to assist you when driv-
ing, the radar sensor system and the camera
system must be switched on and operational. Driving safety systems
87Safety Z

With the help of the radar sensor system and
the camera system, PRE-SAFE ®
Brake can
detect obstacles that are in front of your vehi-
cle for an extended period of time.
In addition, pedestrians in the path of your
vehicle can be detected.
PRE-SAFE ®
Brake detects pedestrians using
typical characteristics such as the body con-
tours and posture of a person standing
upright.
i Observe the restrictions described in the
"Important safety notes" section
(Y page 88).
Important safety notes G
WARNING
PRE-SAFE ®
Brake will initially brake your vehi-
cle by a partial application of the brakes if a
danger of collision is detected. There may be
a collision unless you brake yourself. Even
after subsequent full application of the brakes
a collision cannot always be avoided, partic-
ularly when approaching at too high a speed.
There is a risk of an accident.
Always apply the brakes yourself and try to
take evasive action, provided it is safe to do
so.
In the event of a partial application of the
brakes, the vehicle is braked with up to 50% of
the full braking pressure. G
WARNING
PRE-SAFE ®
Brake cannot always clearly iden-
tify objects and complex traffic conditions.
In these cases, PRE-SAFE ®
Brake may:
R give an unnecessary warning and then
brake the vehicle
R neither give a warning nor intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and be ready to brake, especially if
PRE-SAFE ®
Brake warns you. Terminate the
intervention in a non-critical driving situation. G
WARNING
PRE-SAFE ®
Brake cannot always clearly iden-
tify people, especially if they are moving. In
these cases, PRE-SAFE ®
Brake cannot inter-
vene. There is a risk of an accident.
Always pay particular attention to the traffic
situation and be ready to brake, especially if
PRE-SAFE ®
Brake warns you.
In order to maintain the appropriate distance
to the vehicle in front and thus prevent a col- lision, you must apply the brakes yourself. G
WARNING
PRE-SAFE ®
Brake does not react:
R to small people, e.g. children
R to animals
R to oncoming vehicles
R to crossing traffic
R when cornering
As a result, PRE-SAFE ®
Brake may neither
give warnings nor intervene in all critical sit-
uations. There is a risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake.
In the event of snowfall or heavy rain, detec-
tion can be impaired.
Detection by the radar sensor system is also
impaired in the event of:
R dirt on the sensors or obscured sensors
R interference by other radar sources
R strong radar reflections, for example, in
multi-storey car parks
R a narrow vehicle travelling in front, e.g. a
motorcycle
R a vehicle travelling in front on a different
line
Detection by the camera system is also
impaired in the event of:
R dirt on the camera or if the camera is cov-
ered
R glare on the camera system, e.g. from the
sun being low in the sky 88
Driving safety systemsSafety

R
darkness
R if:
- pedestrians move quickly, e.g. into the
path of the vehicle
- the camera system no longer detects a
pedestrian as a person due to special
clothing or other objects
- a pedestrian is concealed by other
objects
- the typical outline of a person is not dis-
tinguishable from the background
Following damage to the front end of the vehi-
cle, have the radar sensor settings and oper- ation checked at a qualified specialist work-
shop. This also applies to collisions at slow
speeds where there is no visible damage to
the front of the vehicle.
Following damage to the windscreen, have
the configuration and operation of the cam-
era system checked at a qualified specialist
workshop.
Function X
To activate/deactivate: activate or deac-
tivate PRE-SAFE ®
Brake in the on-board
computer (Y page 328).
If the PRE-SAFE ®
Brake is not activated, the
æ symbol appears in the multifunction
display.
If you have activated DSR (Y page 248) PRE-
SAFE ®
Brake is also deactivated.
This function will issue a warning if:
R at a speed of around 30 km/ hor more, the
distance maintained to the vehicle travel-
ling in front is insufficient for several sec-
onds
The · distance warning lamp then lights
up in the instrument cluster.
R at a speed of around 7 km/h or more, you
rapidly approach a vehicle in front or a
pedestrian
An intermittent warning tone will then
sound and the ·distance warning lamp
lights up in the instrument cluster. X
Brake immediately to defuse the situation.
or
X Take evasive action provided it is safe to do
so.
The PRE-SAFE ®
Brake function can also brake
the vehicle automatically under the following
conditions:
R the driver and front passenger have their
seat belts fastened
and
R the vehicle speed is between approx-
imately 7 km/h and 200 km/h
At a speed of up to approximately 70 km/h,
PRE-SAFE ®
Brake can also detect:
R stationary objects in the path of your vehi-
cle, e.g. stopped or parked vehicles
R pedestrians in the path of your vehicle
i If there is an increased risk of a collision,
preventive passenger protection measures
(PRE-SAFE ®
) are activated (Y page 64).
If the risk of a collision with the vehicle in front remains and you do not brake, take evasive
action or accelerate significantly, the vehicle
may perform automatic emergency braking,
up to the point of full brake application. Auto-
matic emergency braking is not performed
until immediately prior to an imminent acci-
dent.
You can prevent the intervention of PRE-
SAFE ®
Brake at any time by:
R depressing the accelerator pedal further
R activating kickdown
R releasing the brake pedal
The braking action of PRE-SAFE ®
Brake is
ended automatically if:
R you manoeuvre to avoid the obstacle
R there is no longer a risk of collision
R there is no longer an obstacle detected in
front of your vehicle Driving safety systems
89Safety Z

Useful information
i This Owner's Manual describes all mod-
els, series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos- sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: (Y page 28). Key
Important safety notes
United Kingdom only: G
WARNING
When the double locks are activated, the
doors can no longer be opened from the
inside. People in the vehicle can no longer get out, e.g. in hazardous situations. There is a
risk of injury.
Therefore, do not leave any people unsuper-
vised in the vehicle, particularly children, eld-
erly people or people in need of special assis-
tance. Do not activate the double lock when
people are in the vehicle.
If the vehicle has been locked from the out-
side, the double lock function is activated as
standard. It is then not possible to open the
doors from inside the vehicle. You can deac-
tivate the double lock function by deactivat-
ing the interior motion sensor (see the sepa-
rate COMAND Online or Audio 20 operating
instructions). The doors can then be opened
from the inside after the vehicle has been
locked from the outside. The anti-theft alarm
system is triggered if the door is opened from
the inside. Switch off the alarm (Y page 90).
All countries: G
WARNING
If children are left unsupervised in the vehicle, they can:
R open doors and endanger other persons or
road users
R climb out and be injured by the traffic
R operate vehicle equipment and, for exam-
ple, trap themselves.
Children could also set the vehicle in motion, for example by:
R releasing the parking brake
R shifting the automatic transmission out of
park position P
R starting the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the key
with you and lock the vehicle. Never leave
children unattended in the vehicle. Always
keep the key out of reach of children. G
WARNING
If you attach heavy or large objects to the key, the key could be unintentionally turned in the
ignition lock. This could cause the engine to
be switched off. There is a risk of an accident.
Do not attach any heavy or large objects to the
key. Remove any bulky keyrings before insert-
ing the key into the ignition lock.
! Keep the key away from strong magnetic
fields. Otherwise, the remote control func-
tion could be affected.
Strong magnetic fields can occur in the
vicinity of powerful electrical installations.
Do not keep the key: R with electronic devices, e.g. a mobile
phone or another key
R with metallic objects, e.g. coins or metal
film
R inside metallic objects, e.g. a metal case
This can affect the key's functionality.
Vehicles with KEYLESS-GO start function: do not keep the key in the luggage compart- 94
KeyOpening and closing

rate COMAND Online or Audio 20 operating
instructions). The doors can then be opened
from the inside after the vehicle has been
locked from the outside. The anti-theft alarm system is triggered if the door is opened from
the inside. Switch off the alarm (Y page 90).
All countries: G
WARNING
If children are left unsupervised in the vehicle, they can:
R open doors and endanger other persons or
road users
R climb out and be injured by the traffic
R operate vehicle equipment and, for exam-
ple, trap themselves.
Children could also set the vehicle in motion, for example by:
R releasing the parking brake
R shifting the automatic transmission out of
park position P
R starting the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the key
with you and lock the vehicle. Never leave
children unattended in the vehicle. Always
keep the key out of reach of children.
Stow luggage or loads preferably in the lug-
gage compartment. Observe the loading
guidelines (Y page 390). Unlocking and opening the doors
from the inside
United Kingdom only: if the vehicle has
been locked with the key or with KEYLESS-
GO, the double lock function is activated as
standard. It is then not possible to open the
doors from inside the vehicle. You can deac-
tivate the double lock function by deactivat-
ing the interior motion sensor . The doors can then be opened from the inside after the vehi-cle has been locked from the outside. You can
only open the rear doors from inside the vehi- cle if they are not secured by the child-proof
locks (Y
page 77). The anti-theft alarm system
is triggered if the door is opened from the
inside. Switch off the alarm (Y page 90).
For all countries except the United King-
dom:
You can open a door from inside the vehicle
even if it has been locked. You can only open
the rear doors from inside the vehicle if they
are not secured by the child-proof locks
(Y page 77). If the vehicle has previously been
locked with the key or with KEYLESS-GO,
opening a door from the inside will trigger the
anti-theft alarm system. Switch off the alarm
(Y page 90). X
Pull door handle ;.
If the door is locked, locking knob :pops
up. The door is unlocked and opens. Centrally locking and unlocking the
vehicle from the inside
You can centrally lock and unlock the vehicle from the inside. The switches are on the driv-
er's door. Doors
101Opening and closing Z

Useful information
i This Owner's Manual describes all mod-
els, series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos- sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: (Y page 28). Running-in notes
Important safety notes
In certain driving and driving safety systems,
the sensors adjust automatically while a cer-
tain distance is being driven after the vehicle has been delivered or after repairs. Full sys-
tem effectiveness is not reached until the end
of this teach-in process.
Brake pads/linings and discs that are either
new or have been replaced only achieve opti- mum braking effect after several hundred kil-
ometres of driving. Compensate for the
reduced braking effect by applying greater
force to the brake pedal. The first 1,500 km
If you treat the engine with sufficient care
from the very start, you will be rewarded with excellent performance for the remainder of
the engine's life.
R Drive at varying road speeds and engine
speeds for the first 1,500 km.
R Avoid overstraining the vehicle during this
period, e.g. driving at full throttle.
R When changing gears manually, change up
in good time, before the rev counter needle
reaches Ôof the way to the red area of the
rev counter. R
Do not shift down a gear manually in order
to brake.
R Try to avoid depressing the accelerator
pedal beyond the point of resistance (kick- down).
After 1,500 km, you may gradually accelerate
the vehicle to full road and engine speeds.
You should also observe these notes on run-
ning-in if the engine or parts of the drive train on your vehicle have been replaced.
Always observe the maximum permissible
speed. Driving
Important safety notes
G
WARNING
Objects in the driver's footwell may restrict
the clearance around the pedals or block a
depressed pedal. This jeopardises the oper-
ating and road safety of the vehicle. There is a risk of an accident.
Stow all objects securely in the vehicle so that
they do not get into the driver's footwell.
Always fit the floormats securely and as pre-
scribed in order to ensure that there is always sufficient room for the pedals. Do not use
loose floormats and do not place several floor-mats on top of one another. G
WARNING
Unsuitable footwear can hinder correct usage of the pedals, e.g.:
R shoes with thick soles
R shoes with high heels
R slippers
There is a risk of an accident.
Wear suitable footwear to ensure correct
usage of the pedals. G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect, 186
DrivingDriving and parking