
Deployment of Emergency Tensioning
Devices and air bags
Important safety notes G
WARNING
The air bag parts are hot after an air bag has
been deployed. There is a risk of injury.
Do not touch the air bag parts. Have a
deployed air bag replaced at a qualified spe-
cialist workshop as soon as possible. G
WARNING
A deployed air bag no longer offers any pro-
tection and cannot provide the intended pro-
tection in an accident. There is an increased
risk of injury.
Have the vehicle towed to a qualified special- ist workshop in order to have a deployed air
bag replaced.
It is important for your safety and that of your
passenger to have deployed air bags replaced and to have any malfunctioning air bags
repaired. This will help to make sure the air
bags continue to perform their protective
function for the vehicle occupants in the
event of a crash. G
WARNING
Pyrotechnic Emergency Tensioning Devices
that have been deployed are no longer opera- tional and are unable to perform their inten-
ded protective function. This poses an
increased risk of injury or even fatal injury.
Therefore, have pyrotechnic Emergency Ten-
sioning Devices which have been triggered
immediately replaced at a qualified specialist workshop.
An electric motor is used by PRE-SAFE ®
to
trigger the tightening of the seat belt in haz-
ardous situations. This procedure is reversi-
ble.
If Emergency Tensioning Devices are trig-
gered or air bags are deployed, you will hear a bang, and a small amount of powder may also be released. The
6restraint system warn-
ing lamp lights up.
Only in rare cases will the bang affect your
hearing. The powder that is released gener-
ally does not constitute a health hazard, but it may cause short-term breathing difficulties in
people with asthma or other respiratory prob-
lems. To avoid this, you may wish to get out of
the vehicle or open the windows as soon as it is safe to do so.
Air bags and pyrotechnic Emergency Tension-
ing Devices (ETDs) contain perchlorate mate-
rial, which may require special handling and
regard for the environment. National guide-
lines must be observed during disposal. In
California, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm .
Method of operation During the first stage of a collision, the
restraint system control unit evaluates impor-
tant physical data relating to vehicle deceler-
ation or acceleration, such as:
R duration
R direction
R intensity
Based on the evaluation of this data, the
restraint system control unit triggers the
Emergency Tensioning Devices during a fron-
tal or rear collision.
An Emergency Tensioning Device can only be triggered, if:
R the ignition is switched on
R the components of the restraint system are
operational; see "Restraint system warning lamp" (Y page 50)
R the belt tongue is engaged in the buckle on
the respective front-passenger seat
The Emergency Tensioning Devices in the
rear compartment are triggered independ-
ently of the lock status of the seat belts. Occupant safety
65Safety Z

The side impact air bag on the front-
passenger side (front) deploys in the fol-
lowing situations:
- the OCS system detects that the front-
passenger seat is occupied or
- the belt tongue is engaged in the belt
buckle of the front-passenger seat
R Window curtain air bag on the side of
impact, independently of the use of the
seat belt and independently of whether the front-passenger seat is occupied
R Window curtain air bags on the driver's and
front-passenger side in certain situations
when the vehicle rolls over, if the system
determines that deployment can offer addi-
tional protection to that provided by the
seat belt
i Not all air bags are deployed in an acci-
dent. The different air bag systems work
independently of each other.
How the air bag system works is deter-
mined by the severity of the accident detec- ted, especially the vehicle deceleration or
acceleration and the apparent type of acci-dent:
R frontal collision
R side impact
R rollover PRE-SAFE
®
(anticipatory occupant
protection system)
Introduction In certain hazardous situations, PRE-SAFE
®
takes pre-emptive measures to protect the
vehicle occupants.
Important safety notes !
Make sure that there are no objects in the
footwell under or behind the seats when
moving the seats back. There is a risk that
the seats and/or the objects could be dam-
aged. Despite your vehicle being equipped with the
PRE-SAFE ®
system, the possibility of per-
sonal injuries occurring as a result of an acci- dent cannot be eliminated. Always adapt your
driving style to suit the prevailing road and
weather conditions and maintain a safe dis-
tance from the vehicle in front. Drive care-
fully.
Function PRE-SAFE
®
intervenes:
R in emergency braking situations, e.g. when
BAS is activated
R in critical driving situations, e.g. when phys-
ical limits are exceeded and the vehicle
understeers or oversteers severely
R vehicles with the Driving Assistance pack-
age: when a driver assistance system inter-
venes powerfully or the radar sensor sys-
tem detects an imminent danger of colli-
sion in certain situations
PRE-SAFE ®
takes the following measures
depending on the hazardous situation detec-
ted:
R the front seat belts are pre-tensioned.
R if the vehicle skids, the panorama roof with
power tilt/sliding panel and the side win-
dows are closed so that only a small gap
remains.
R the front-passenger seat is adjusted if it is
in an unfavorable position.
R for vehicles with electrically adjustable rear
seats: the outer rear seats are adjusted if
they are in an unfavorable position.
R vehicles with a multicontour seat: the air
pressure in the side bolsters of the seat
backrest is increased.
R vehicles with seat belt extenders: the seat
belts of the outer rear seats are pre-ten-
sioned.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pre-tensioning. On vehicles with mul-
ticontour seats, the air pressure in the side Occupant safety
67Safety Z

G
WARNING
Child restraint systems or their securing sys-
tems which have been damaged or subjected to a load in an accident can no longer protect
as intended. The child cannot then be
restrained in the event of an accident, heavy
braking or sudden changes of direction. There is an increased risk of injury, possibly even
fatal.
Replace child restraint systems which have
been damaged or subjected to a load in an
accident as soon as possible. Have the secur-
ing systems on the child restraint system
checked at a qualified specialist workshop,
before you install a child restraint system
again.
The securing systems of child restraint sys-
tems are:
R the seat belt system
R the LATCH-type (ISOFIX) securing rings
R the Top Tether anchorages
If it is absolutely necessary to carry a child on the front-passenger seat, be sure to observe
the information on the "Occupant Classifica-
tion System (OCS)" (Y page 59). There you
will also find information on deactivating the
front-passenger front air bag.
All child restraint systems must meet the fol- lowing standards:
R U.S. Federal Motor Vehicle Safety Stand-
ards 213 and 225
R Canadian Motor Vehicle Safety Standards
213 and 210.2
Confirmation that the child restraint system
corresponds to the standards can be found
on an instruction label on the child restraint
system. This confirmation can also be found
in the installation instructions that are inclu-
ded with the child restraint system.
Observe the warning labels in the vehicle inte-
rior and on the child restraint system. Vehicles with seat belt extenders:
when
securing a child in a child restraint system on
a rear seat, observe the following instruc-
tions:
R make sure that the seat belt on the child
restraint system is fastened according to
the manufacturer's installation instruc-
tions for the child restraint system.
R for child restraint systems with a belt
clamp: engage the belt tongue in the buckle
before you tighten the seat belt using the
belt clamp.
Vehicles with a rear reclining seat: when
installing a child restraint system, move the
rear reclining seat backrest to an almost ver-
tical position. The rear reclining seat backrest
must rest against the child restraint system.
Observe the notes on the cushion air bag
(Y page 59).
Vehicles with belt bags: only use a child
restraint system which has been approved by
Mercedes-Benz. Always observe the instruc-
tions and safety notes on belt bags for the
outer seat belts in the rear (Y page 53). LATCH-type (ISOFIX) child seat secur-
ing system G
WARNING
LATCH-type (ISOFIX) child restraint systems
do not offer sufficient protective effect for
children whose weight is greater than 48 lbs
(22 kg) who are secured using the safety belt integrated in the child restraint system. In the
event of an accident, a child might not be
restrained correctly. This poses an increased
risk of injury or even fatal injury.
If the child weighs more than 48 lbs (22 kg),
only use LATCH-type (ISOFIX) child restraint
systems with which the child is also secured
with the vehicle seat belt. Also secure the
child restraint system with the Top Tether
belt, if available. Children in the vehicle
71Safety Z

When the override feature is activated, the
controls in the rear compartment are disabled
for:
R the rear side windows
R adjustment of the front-passenger seat
from the rear compartment
R the sunblinds:
- of the rear side windows
- of the rear window
- in the roof Pets in the vehicle
G
WARNING
If you leave animals unattended or unsecured in the vehicle, they could press buttons or
switches, for example.
As a result, they could:
R activate vehicle equipment and become
trapped, for example
R activate or deactivate systems, thereby
endangering other road users
Unsecured animals could also be flung around
the vehicle in the event of an accident or sud- den steering or braking, thereby injuring vehi-
cle occupants. There is a risk of an accident
and injury.
Never leave animals unattended in the vehi-
cle. Always secure animals properly during
the journey, e.g. use a suitable animal trans-
port box. 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 76)
R BAS ( Brake Assist System) (Y page 77)
R BAS PLUS (Brake AssistSystem PLUS) with
Cross-Traffic Assist (Y page 77)R
COLLISION PREVENTION ASSIST PLUS
(distance warning function and Adaptive
Brake Assist) (Y page 79)
R ESP ®
(Electronic StabilityProgram)
(Y page 81)
R EBD ( Electronic Brake force Distribution)
(Y page 83)
R ADAPTIVE BRAKE (Y page 84)
R PRE-SAFE ®
Brake (Y page 84)
R STEER CONTROL (Y page 86) Important safety notes
If you fail to adapt your driving style or if you
are inattentive, the driving safety systems can
neither reduce the risk of an accident nor
override the laws of physics. Driving safety
systems are merely aids designed to assist
driving. You are responsible for maintaining
the distance to the vehicle in front, for vehicle
speed, for braking in good time and for stay-
ing in lane. Always adapt your driving style to
suit the prevailing road and weather condi-
tions and maintain a safe distance from the
vehicle in front. Drive carefully.
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 442).
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 vehi-
cle when braking. 76
Driving safety systemsSafety

If the autonomous braking function requires a
particularly high braking force, preventative
passenger protection measures (PRE-SAFE ®
)
are activated simultaneously.
Adaptive Brake Assist i
Observe the "Important safety notes" sec-
tion (Y page 76).
Adaptive Brake Assist provides braking assis-
tance in hazardous situations at speeds
above 4 mph (7 km/h). It uses radar sensor
technology to assess the traffic situation. 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, the brake system remains available with full
brake boosting effect and BAS.
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 col-
lision 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.
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.
If adaptive Brake Assist demands particularly
high braking force, preventative passenger
protection measures (PRE-SAFE ®
) are activa-
ted simultaneously.
Up to a speed of approximately 155 mph
(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.
Up to a speed of approximately 44 mph
(70 km/h), adaptive Brake Assist reacts to
stationary obstacles. ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes" sec-
tion (Y page 76).
ESP ®
monitors driving stability and traction,
i.e. power transmission between the tires and
the road surface. Driving safety systems
81Safety Z

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) i
Observe the "Important safety notes" sec-
tion (Y page 76).
ETS traction control is part of ESP ®
. On vehi-
cles with 4MATIC, 4ETS 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, even if you
deactivate ESP ®
.
Important safety notes G
WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilize the vehicle. Additionally, further driv- ing 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 without 4MATIC: observe the notes
on ESP ®
(Y page 437) when towing the vehi-
cle with a raised rear axle.
ESP ®
is only deactivated if the åwarning
lamp is lit continuously.
If the ÷ warning lamp lights up continu-
ously, ESP ®
is not available due to a malfunc-
tion.
Observe the information on warning lamps
(Y page 360) and display messages which
may be shown in the instrument cluster
(Y page 317). Only use wheels with the recommended tire
sizes. Only then will ESP ®
function properly.
Characteristics of ESP ® General information
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 Only depress the accelerator pedal as far as
necessary when pulling away.
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 when the vehicle
stops moving. The engine starts automati-
cally when the driver wants to pull away again. ESP ®
remains in its previously selected sta-
tus. Example: if ESP®
was deactivated before
the engine was switched off, ESP ®
remains
deactivated when the engine is switched on
again.
Deactivating/activating ESP ® Important safety notes
i Observe the "Important safety notes" sec-
tion (Y page 76).
You can select between the following states
of ESP ®
:
R ESP ®
is activated.
R ESP ®
is deactivated. G
WARNING
If you deactivate ESP ®
, ESP ®
no longer sta-
bilizes the vehicle. There is an increased risk
of skidding and an accident. 82
Driving safety systemsSafety

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
i Activate ESP ®
as soon as the situations
described above no longer apply. ESP ®
will
otherwise not be able to stabilize the vehi-
cle if the vehicle starts to skid or a wheel
starts to spin.
! Avoid spinning the driven wheels for an
extended period with ESP ®
deactivated.
You could otherwise damage the drivetrain.
Deactivating/activating ESP ®
You can deactivate or activate ESP ®
via the
on-board computer.
X To deactivate: (Ypage 82).
The å ESP®
OFF warning lamp in the
instrument cluster lights up.
X To activate: (Ypage 82).
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 stabilize 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 ESP ®
still provides support when you
brake. Crosswind Assist (vehicles without
MAGIC BODY CONTROL) General information
Vehicles with MAGIC BODY CONTROL: infor-
mation on stabilizing the vehicle in the event
of crosswind (Y
page 243).
Strong crosswinds can cause your vehicle to
deviate from a straight course. The crosswind
driving assistance function integrated into
ESP ®
significantly reduces these effects.
ESP ®
intervenes automatically according to
the direction and intensity of the crosswinds
affecting your vehicle.
ESP intervenes with stabilizing braking to
assist you in keeping the vehicle in the lane.
Crosswind Assist is active at vehicle speeds
above 50 mph (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 information 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 76). 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. Driving safety systems
83Safety Z

Observe information regarding indicator and
warning lamps (Y page 358) as well as dis-
play messages (Y page 320).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 242) and
hill start assist (Y page 192). PRE-SAFE
®
Brake
General information i
Pay attention to the important safety
notes in the "Driving safety systems" sec-
tion (Y page 76).
PRE‑SAFE ®
Brake is only available for vehi-
cles with the Driving Assistance package.
For PRE-SAFE ®
Brake to assist you when driv-
ing, the radar sensor system and the camera
system must be switched on and be opera-
tional.
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.
Observe the restrictions described in the
"Important safety notes" sec-
tion“ (Y page 84).
PRE-SAFE ®
Brake can help you to minimize
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 collision, you will be warned visually
and acoustically as well as by automatic brak- ing. 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. 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 not give a warning or 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.
In order to maintain the appropriate distance
to the vehicle in front and thus prevent a col- lision, you must apply the brakes yourself.
PRE-SAFE ®
Brake 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 4 mph (7 km/h) and 124 mph
(200 km/h)
At a speed of up to approximately 44 mph
(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 84
Driving safety systemsSafety