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 notes ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the vehi- cle when braking.
The ! ABS warning lamp in the instrument
cluster lights up when the ignition is switched on. It goes out when the engine is running.
ABS works from a speed of about 8 km/h,
regardless of road-surface conditions. ABS
works on slippery surfaces, even when you
only brake gently.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 78). G
WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid- ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
If ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information on the ABS warning lamp (Y page 379) and
display messages which may be shown in the
instrument cluster (Y page 336). Brakes X
If ABS intervenes: continue to depress the
brake pedal with force until the braking sit- uation is over.
X To make a full brake application:
depress the brake pedal with full force.
If ABS intervenes when braking, you will feel a pulsing in the brake pedal.
The pulsating brake pedal can be an indica-
tion of hazardous road conditions; this serves
as a reminder to take extra care while driving.
Off-road ABS An ABS system specifically suited to off-road
terrain is activated automatically once the off- road program is activated (Y page 250).
At speeds below 30 km/h the front wheels
lock cyclically during braking. The digging-in
effect achieved in the process reduces the
stopping distance when driving off-road. This limits steering capability. BAS (Brake Assist)
General notes BAS operates in emergency braking situa-
tions. If you depress the brake pedal quickly,
BAS automatically boosts the braking force,
thus shortening the stopping distance.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 78). G
WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking. Driving safety systems
79Safety Z
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
If ESP
®
detects that the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilise 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 stabilise the vehicle during braking.
4ETS (Electronic Traction System) i
Observe the "Important safety notes" sec-
tion (Y page 78).
4ETS traction control is part of ESP ®
.
Traction control brakes the drive wheels indi-
vidually 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 trans-
ferred to the wheel or wheels with traction.
Traction control remains active if you deacti-
vate ESP ®
.
Off-road 4ETS (Electronic Traction Sys-
tem) A 4ETS system specifically suited to off-road
terrain is activated automatically once the off- road program is activated (Y page 250).
Off-road ESP ® An ESP
®
system specifically suited to off-road
terrain is activated automatically once the off-
road program is activated (Y page 250).
The off-road ESP ®
intervenes with a delay if
there is oversteering or understeering, thus
improving traction.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 78). G
WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilise the vehicle. In addition, other driving safety systems are switched off. This increa-
ses the risk of skidding and an accident.
Drive on carefully. Have ESP
®
checked at a
qualified specialist workshop.
If the å ESP®
OFF warning lamp lights up
continuously, ESP ®
is deactivated.
If the ÷ ESP®
warning lamp lights up con-
tinuously, ESP ®
is not available due to a mal-
function.
Observe the information on warning lamps
(Y page 381) and display messages which
may be shown in the instrument cluster
(Y page 336).
Only use wheels with the recommended tyre
sizes. Only then will ESP ®
function properly.
Characteristics of ESP ® General notes
If the
÷ ESP warning lamp goes out before
beginning the journey, ESP ®
is automatically
active.
If ESP ®
intervenes, the ÷ESP®
warning
lamp flashes in the instrument cluster.
If ESP ®
intervenes:
X Do not deactivate ESP ®
under any circum-
stances.
X When pulling away, only depress the accel-
erator pedal as far as is necessary.
X Adapt your driving style to suit the prevail-
ing road and weather conditions.
ECO start/stop function
The ECO start/stop function switches the
engine off automatically if the vehicle stops
moving. When pulling away again, the engine starts automatically. ESP ®
remains in its pre-
viously selected status. Example:if ESP®
was deactivated before the engine was
switched off, ESP ®
remains deactivated when
the engine is switched on again. Driving safety systems
85Safety Z
Deactivating/activating ESP
®Important safety notes
i Observe the "Important safety notes" sec-
tion (Y page 78).
You can select between the following sta-
tuses of ESP ®
:
R ESP ®
is activated
R ESP ®
is deactivated G
WARNING
If you deactivate ESP ®
, ESP ®
no longer sta-
bilises the vehicle. There is an increased risk
of skidding and an accident.
Only deactivate ESP ®
in the situations descri-
bed in the following.
It may be best to deactivate ESP ®
in the fol-
lowing situations:
R when using snow chains
R in deep snow
R on sand or gravel
R when driving off-road (vehicles without off-
road program)
Activate ESP ®
as soon as the situations
described above no longer apply. ESP ®
will
otherwise not be able to stabilise the vehicle if the vehicle starts to skid or a wheel starts to
spin.
Deactivating/activating ESP ®X
To deactivate: press button:.
The å ESP®
OFF warning lamp in the
instrument cluster lights up. X
To activate: press button :.
The å ESP®
OFF warning lamp in the
instrument cluster goes out.
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 flashes. In such situa-
tions, ESP ®
will not stabilise the vehicle.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability
R engine torque is no longer limited and the
drive wheels are able to spin
The spinning of the wheels results in a cut-
ting action for better traction on loose sur- faces.
R Traction control is still activated
R COLLISION PREVENTION ASSIST is no lon-
ger available; nor is it activated if you brake
firmly with assistance from ESP ®
R PRE-SAFE ®
is no longer available; it is also
not activated if you brake firmly with assis-
tance from ESP ®
R PRE-SAFE ®
Brake is no longer available; it
is also not activated if you brake firmly with
assistance from ESP ®
R ESP ®
still provides support when you brake
firmly
ESP ®
trailer stabilisation General notes
If your vehicle/trailer combination begins to
lurch, ESP
®
assists you in this situation. ESP ®
slows the vehicle down by braking and limit-
ing the engine output until the vehicle/trailer combination has stabilised.
Important safety notes G
WARNING
If road and weather conditions are poor,
trailer stabilisation will not be able to prevent the vehicle/trailer combination from swerv-
ing. Trailers with a high centre of gravity can 86
Driving safety syste
msSafety
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
4
Ã
Automatic headlamp mode, control-
led by the light sensor
5 L
Dipped-beam/main-beam head-
lamps
B R
Rear foglamp
If you hear a warning tone when you leave the
vehicle, the lights may still be switched on.
X Turn the light switch to the Ãposition.
The exterior lighting (except the side lamps/
parking lamps) switches off automatically if
you:
R remove the key from the ignition lock
R open the driver's door with the key in posi-
tion 0in the ignition lock.
Automatic headlamp mode
à is the preferred light switch setting. The
light setting is automatically selected accord- ing to the brightness of the ambient light
(exception: poor visibility due to weather con-
ditions such as fog, snow or spray):
R key in position 1in the ignition lock: the
side lamps are switched on or off automat- ically depending on the brightness of the
ambient light
R With the engine running: depending on the
ambient light conditions, the daytime driv-
ing lights or the parking and dipped-beam
headlamps are switched on or off automat- ically
X To switch on the automatic headlamps:
turn the light switch to the Ãposition. G
WARNING
When the light switch is set to Ã, the
dipped-beam headlamps may not be switched on automatically if there is fog, snow or othercauses of poor visibility due to the weather
conditions such as spray. There is a risk of an
accident.
In such situations, turn the light switch to
L. The automatic headlamp feature is only an
aid. The driver is responsible for the vehicle
lighting at all times.
The daytime driving lights improve the detect-
ability of your vehicle during the day.
When the side lamps and dipped-beam head-lamps are switched on, the green T(side
lamps) and L(dipped-beam headlamps)
indicator lamps in the instrument cluster light
up.
Dipped-beam headlamps
When the ignition is switched on and the light
switch is in the Lposition, the side lamps
and dipped-beam headlamps are switched on even if the light sensor does not sense dark
ambient light conditions. This is advanta-
geous when there is fog or rain.
X To switch on the dipped-beam head-
lamps: turn the key in the ignition lock to
position 2or start the engine.
X Turn the light switch to the Lposition.
The green Lindicator lamp in the instru-
ment cluster lights up.
Rear foglamp
The rear foglamp improves the visibility of
your vehicle in heavy fog for the following
traffic. Please observe the country-specific
laws on the use of rear foglamps.
X To switch on the rear foglamp: turn the
key in the ignition lock to position 2or start
the engine.
X Turn the light switch to the LorÃ
position.
X Press the Rbutton.
The yellow Rindicator lamp in the
instrument cluster lights up.
X To switch off the rear foglamp: press the
R button.
The yellow Rindicator lamp in the
instrument cluster goes out. Exterior lighting
139Lights andwindscreen wipers Z
Main-beam headlamps
X
To switch on manually: turn the key to
position 2in the ignition lock or start the
engine.
X Vehicles without Adaptive Highbeam Assist
Plus: turn the light switch to LorÃ.
X Vehicles with Adaptive Highbeam Assist
Plus: turn the light switch to L.
X Press the combination switch beyond the
pressure point in the direction of arrow :.
In the Ãposition, the main-beam head-
lamps are only switched on when it is dark
and the engine is running.
The blue Kindicator lamp in the instru-
ment cluster lights up when the main-beam
headlamps are switched on.
X To deactivate: move the combination
switch back to its normal position.
The blue Kindicator lamp in the instru-
ment cluster goes out.
Vehicles with Adaptive Highbeam Assist
Plus: when Adaptive Highbeam Assist Plus is
activated, it automatically controls activation and deactivation of the main-beam head-
lamps (Y page 143).
Headlamp flasher X
To switch on: turn the key in the ignition
lock to position 1or 2, or start the engine.
X Pull the combination switch in the direction
of arrow =. Hazard warning lamps X
To switch on the hazard warning lamps:
press button :.
All turn signals flash. If you now switch on a turn signal using the combination switch,
only the turn signal lamp on the corre-
sponding side of the vehicle will flash.
X To switch off the hazard warning lamps:
press button :.
The hazard warning lamps switch on auto-
matically if:
R an airbag is deployed or
R the vehicle decelerates rapidly from a
speed of above 70 km/h and comes to a
standstill
The hazard warning lamps switch off auto-
matically if the vehicle reaches a speed of
above 10 km/h again after a full brake appli- cation.
The hazard warning lamps continue to oper-
ate even if the ignition is switched off. Intelligent Light System
General notes The Intelligent Light System is a system that
adjusts the headlamps automatically to suit
the prevailing driving and weather conditions. It offers advanced functions for improved illu-
mination of the road surface, e.g. depending
on the vehicle speed or weather conditions.
The system includes the active light function, cornering light function, motorway mode,
extended range foglamps and off-road lights.
The system is only active when it is dark.
You can activate or deactivate the "Intelligent Light System" function using the on-board
computer (Y page 331). Exterior lighting
141Lights and windscreen wipers Z