Deployment of belt tensioners and air-
bags
Important safety notes G
WARNING
After the airbag deploys, the airbag parts are
hot. There is a risk of injury.
Do not touch the airbag parts. Have a
deployed airbag replaced at a qualified spe-
cialist workshop as soon as possible. G
WARNING
Pyrotechnic seat belt tensioners that have
been deployed are no longer operational and
are unable to perform their intended protec-
tive function. This poses an increased risk of
injury or even fatal injury.
Therefore, have pyrotechnic belt tensioners
which have been triggered immediately
replaced at a qualified specialist workshop.
Mercedes-Benz recommends that you have
the vehicle towed to a qualified specialist
workshop after an accident. Take this into
account, particularly if a seat belt tensioner
was triggered or an airbag was deployed.
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 the belt tensioners are triggered or an air-
bag is deployed, you will hear a bang, and a
small amount of powder may also be
released. The 6restraint system warning
lamp lights up.
Only in rare cases will the bang affect your
hearing. In general, the powder released is
not hazardous to health but may cause short- term breathing difficulties to persons suffer-
ing from asthma or other pulmonary condi-
tions. Provided it is safe to do so, you should
leave the vehicle immediately or open the
window in order to prevent breathing difficul- ties. 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 seat
belt tensioners in the event of a head-on or
rear collision.
A seat belt tensioner can only be triggered if:
R the ignition is switched on
R the components of the restraint system are
operational. You can find further informa-
tion under: "Restraint system warning
lamp" (Y page 43)
R the belt tongue has engaged in the belt
buckle of the respective front seat
The seat belt tensioners in the rear compart-
ment are triggered independently of the lock
status of the seat belts.
If the restraint system control unit detects a
high severity accident, in certain head-on col- lisions, additional components of the
restraint system are deployed independently
of each other:
R front airbags and driver's kneebag
R windowbag, if the system determines that
deployment can offer additional protection
to that provided by the seat belt
On vehicles with the automatic front-
passenger front airbag deactivation system:
depending on the person in the front-
passenger seat, the front-passenger front air- bag is either disabled or enabled. The front-
passenger front airbag can only be deployed
in an accident if the PASSENGER AIR BAG ON
indicator lamp is lit. Observe the information
on the PASSENGER AIR BAG indicator lamps
(Y page 43).
Your vehicle has two-stage front airbags. In
the first deployment stage, the front airbag is Occupant safety
57Safety Z
filled with propellant gas to reduce the risk of
injuries. The front airbag is fully deployed if
the second deployment stage is activated
within a few milliseconds.
The activation threshold for the seat belt ten-
sioners and airbags is determined based on
the evaluation of the vehicle's rate of decel-
eration or acceleration at various points in the vehicle. This process is pre-emptive in nature.The triggering/deployment process should
take place in good time at the start of the
collision.
The rate of vehicle deceleration or accelera-
tion and the direction of the force are essen- tially determined by:
R the distribution of forces during the colli-
sion
R the collision angle
R the deformation characteristics of the vehi-
cle
R the characteristics of the object with which
the vehicle has collided
Factors which can only be seen and measured
after a collision has occurred do not play a
decisive role in the deployment of an airbag,
nor do they provide an indication of airbag
deployment.
The vehicle may be deformed significantly
without an airbag being deployed. This is the
case if only parts which are relatively easily
deformed are affected and the rate of decel-
eration is not high. Conversely, an airbag may
be deployed even though the vehicle suffers
only minor deformation. This is the case if, for example, very rigid vehicle parts such as lon-
gitudinal body members are hit, and sufficient deceleration occurs as a result.
If the restraint system control unit detects a
side impact, the applicable components of
the restraint system are activated independ-
ently of each other.
R Sidebags on the side on which an impact
occurs, independent from the seat belt ten-
sioner and seat belt usage
Vehicles with the automatic front-
passenger airbag deactivation system: the sidebag on the front-passenger side
deploys under the following conditions:
- an occupant is detected on the front-
passenger seat or
- the belt tongue is engaged in the belt
buckle of the front-passenger seat
R Windowbag on the side on which an impact
occurs, independent of seat belt usage and
regardless of whether the front-passenger
seat is occupied
R Seat belt tensioners, if the system deter-
mines that deployment can offer additional
protection for the vehicle occupants in this situation
i Not all airbags are deployed in an acci-
dent. The different airbag systems work
independently of each other.
How the airbag 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 PRE-SAFE
®
(anticipatory occupant
protection)
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 or behind the seats. There is a risk that the seats and/or the objects could be
damaged when PRE-SAFE ®
is activated.
Although your vehicle is equipped with PRE-
SAFE ®
, the possibility of injury in the event of
an accident cannot be ruled out. Always
adapt your driving style to suit the prevailing
road and weather conditions and maintain a 58
Occupant safetySafety
safe distance from the vehicle in front. Drive
carefully.
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 on vehicles with DISTRONIC PLUS: if adap-
tive Brake Assist intervenes powerfully
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 side windows and
the panorama sliding sunroof are closed.
R vehicles with the memory function: the
front-passenger seat is adjusted if it is in an
unfavourable position.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pre-tensioning. All settings made by
PRE-SAFE ®
can then be reversed.
If the seat belt pre-tensioning is not reduced:
X Move the seat backrest or seat back
slightly when the vehicle is stationary.
Seat belt pre-tensioning is reduced and the locking mechanism is released.
The seat-belt adjustment is an integral part of
the PRE-SAFE ®
convenience function. Infor-
mation about the convenience function can
be found under "Belt adjustment"
(Y page 47). Automatic measures after an acci-
dent
Immediately after an accident, the following
measures may be implemented, depending
on the type and severity of the impact:
R the hazard warning lamps are activated
R the emergency lighting is activated
R the vehicle doors are unlocked
R the front side windows are lowered
R the engine is switched off and the fuel sup-
ply is cut off
R vehicles with the Mercedes-Benz emer-
gency call system: automatic emergency
call Children in the vehicle
Important safety notes
Accident statistics show that children
secured in the rear seats are safer than chil-
dren secured in the front-passenger seat. For this reason, Mercedes-Benz strongly advises
that you install a child restraint system on a
rear seat. Children are generally better pro-
tected there.
If a child younger than twelve years old and
under 1.50 m in height is travelling in the
vehicle:
R always secure the child in a child restraint
system suitable for Mercedes-Benz vehi-
cles. The child restraint system must be
appropriate to the age, weight and size of
the child.
R be sure to observe the instructions and
safety notes in this section in addition to
the child restraint system manufacturer's
installation instructions.
R always pay attention to the instructions
and safety notes on the automatic front-
passenger front airbag deactivation system (Y page 51). Children in the vehicle
59Safety Z
You can thus avoid the risks that could arise
as a result of:
R a child restraint system that is not detected
by the automatic front-passenger front air-
bag deactivation system
R the unintentional disabling of the front-
passenger front airbag
R the unsuitable positioning of the child
restraint system, e.g. too close to the dash- board Please observe the warning notice on the
front-passenger sun visor, see the illustra-
tion. G
WARNING
If you secure a child on the co-driver's seat in a rearward-facing child restraint system and
the PASSENGER AIR BAG ON indicator lamp
lights up, the co-driver's airbag could be
deployed in the event of an accident. The childcould be struck by the airbag. There is an
increased risk of injury, possibly even fatal.
In this case, always ensure that the co-driver's
airbag is disabled. The PASSENGER AIRBAG
OFF indicator lamp must light up.
NEVER use a rearward facing child restraint
on a seat protected by an ACTIVE AIRBAG in
front of it; DEATH or SERIOUS INJURY to the
CHILD can occur.
If the PASSENGER AIR BAG ON indicator lamp
is lit, the front-passenger front airbag is ena-
bled (Y page 43). Vehicles without the automatic front-
passenger front airbag deactivation
system
If the front-passenger seat of your vehicle is
not equipped with the automatic front-
passenger front airbag deactivation system,
this is indicated by a special sticker. The
sticker is affixed to the side of the dashboard
on the front-passenger side. The sticker is
visible when you open the front-passenger
door.
If you turn the key to position 2in the ignition
lock, the PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps
light up briefly. However, they have no func-
tion and do not indicate that there is an auto- matic front-passenger front airbag deactiva-
tion system.
Always fit the rearward-facing restraint sys-
tem to a suitable rear seat in this case
(Y page 65).
Observe the following information under
"Rearward-facing child restraint system" and
"Forward-facing child restraint system" as
well as information on the suitable position-
ing of the child restraint system
(Y page 65).
Rearward-facing child restraint system If it is absolutely necessary to fit a rearward-
facing child restraint system to the front-
passenger seat, always make sure that the
front-passenger front airbag is disabled. Only
if the PASSENGER AIR BAG OFF indicator 64
Children in the vehicleSafety
Suitability of the seats for attaching a belt-secured child restraint system
If you use a baby car seat of category 0 or 0+ or a rearward-facing child restraint system of
category I on a rear seat, you must adjust the driver's or front-passenger seat so that the seat
does not touch the child restraint system.
If you use a category I, forward-facing child restraint system, you should remove the head
restraint of the respective seat (Y page 116), if possible. The backrest of the child restraint
system must, as far as possible, lie flat against the backrest of the seat.
Always observe the notes in the "Child restraint system" section (Y page 60) and the child
restraint system manufacturer's installation instructions.
When you remove the child restraint system you must replace the head restraints again
immediately (Y page 115). All vehicle occupants must adjust their head restraints correctly
before beginning the journey.
Legend for the table:
XS eat which is unsuitable for children in this weight category.
US uitable for child restraint systems in the "Universal" category that are approved for use
in this weight category.
UF Suitable for forward-facing child restraint systems that belong to the "Universal" category and are approved for use in this weight category.
LS uitable for child restraint systems as recommended; see the "Recommended child
restraint systems" table (Y page 69). Suitable for semi-universal child restraint systems
if the vehicle and the seat are listed in the child restraint system manufacturer's vehicle
model list. Weight category Front-passenger seat Rear seat
Front-
passenger
front airbag
enabled Front-
passenger
front airbag
deactiva-
ted 1 Left, right
Centre
2 0
up to 10 kg X U, L U, L U, L
0+
up to 13 kg X U, L U, L U, L
I
9 kg to 18 kg UF, L U, L U, L U, L
II
15 kg to 25 kg U, L U, L U, L X
III
22 kg to 36 kg U, L U, L U, L X
1
The vehicle is equipped with an automatic front-passenger front airbag deactivation system. The PASSENGER
AIR BAG OFF indicator lamp must be lit.
2 Child restraint systems with a supporting bracket are not suitable for this seat. Children in the vehicle
67Safety Z
The seat belt should:
R fit snugly across your body
R be routed across the middle of your
shoulder
R be routed across your hips in the pelvic
area
X Before starting off, adjust the rear-view mir-
ror and the exterior mirrors (Y page 119)
so that you have a good view of road and
traffic conditions.
X Vehicles with a memory function: save
the seat and exterior mirror settings
(Y page 122). Seats
Important safety notes
G
WARNING
If children adjust the seats, they could
become trapped, especially if they are unat-
tended. There is a risk of injury.
When leaving the vehicle, always take the key with you and lock the vehicle. Never leave
children unattended in the vehicle.
The seats can still be adjusted when there is
no key in the ignition lock. G
WARNING
When adjusting a seat, you or another vehicle occupant could become trapped by the guiderail of the seat, for instance. There is a risk of
injury.
Make sure that no one has any part of their
body within the sweep of the seat when
adjusting it.
Observe the safety notes on "Airbags"
(Y page 48) and "Children in the Vehicle"
(Y page 59). G
WARNING
If the driver's seat is not correctly engaged, it could unexpectedly move while driving. This could cause you to lose control of the vehicle.
There is a risk of an accident.
Always ensure that the driver's seat is
engaged before starting the vehicle. G
WARNING
You could lose control of the vehicle while
driving if you:
R adjust the driver's seat, steering wheel or
mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirrors and fasten your seat
belt before starting the engine. G
WARNING
If you adjust the seat height carelessly, you or other vehicle occupants could be trapped andthereby injured. Children in particular could
accidentally press the electrical seat adjust-
ment buttons and become trapped. There is a
risk of injury.
While moving the seats, make sure that your
hands or other body parts do not get under the
lever assembly of the seat adjustment sys-
tem.
! To avoid damage to the seats and the seat
heating, observe the following information:
R do not spill any liquids on the seats. If
liquid is spilled on the seats, dry them as
soon as possible.
R if the seat covers are damp or wet, do not
switch on the seat heating. The seat
heating should also not be used to dry
the seats.
R clean the seat covers as recommended;
see the "Interior care" section.
R do not transport heavy loads on the
seats. Do not place sharp objects on the
seat cushions, e.g. knives, nails or tools. Seats
113Seats, steering wheel and mirrors Z
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/ha gain 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 and
extended range foglamps. 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 259).
Active light function The active light function is a system that
moves the headlamps according to the steer-
ing movements of the front wheels. In this way, relevant areas remain illuminated while
you are driving. This allows you to recognise
pedestrians, cyclists and animals.
Active:
when the lights are switched on.
Cornering light function The cornering light function improves the illu-
mination of the road over a wide angle in the direction you are turning, enabling better vis-
ibility in tight bends, for example. It can only
be activated when the dipped-beam head-
lamps are switched on.
Active:
R if you are driving at speeds below 40 km/h
and switch on the turn signal or turn the
steering wheel.
R if you are driving at speeds between
40 km/ha nd 70 km/h and turn the steer-
ing wheel.
The cornering light function may remain lit for
a short time, but is automatically switched off after no more than three minutes.
Motorway mode 130
Exterior lightingLights and
windscreen wipers
Display messages
Possible causes/consequences and
M
MSolutions PRE-SAFE inopera‐
PRE-SAFE inopera‐
tive See Owner's tive See Owner's
Manual Manual
Important functions of PRE-SAFE
®
have failed. All other occupant
safety systems, e.g. airbags, remain available.
X Consult a qualified specialist workshop immediately. Radar sensors
Radar sensors
dirty See Owner's dirty See Owner's
Manual Manual At least one of the following driving systems or driving safety sys-
tems is temporarily restricted or inoperative:
R COLLISION PREVENTION ASSIST PLUS
R DISTRONIC PLUS
Possible causes:
R the sensors in the radiator trim and/or in the bumpers are dirty
R the function of the driving system and/or driving safety system
is impaired due to heavy rain or snow
A warning tone also sounds.
Once the causes listed above no longer apply, the display message
goes out. All driving systems and driving safety systems are opera- tional again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Safeguard the vehicle against rolling away (Y page 192).
X Switch off the engine.
X Clean the sensors (Y page 344) in the following locations:
R in the radiator trim
R in the front bumper
R in the rear bumper, particularly in the middle of the rear
bumper
X Restart the engine.
The display message disappears. ü If this symbol appears in the multifunction display, a seat belt
tongue has been inserted into a rear seat belt buckle.
Further information on the status indicator for the rear seat belts
(Y page 48). 274
Display
messagesOn-board computer and displays