Problems with automatic front-passenger front airbag deactivation
Be sure to observe the notes on "System self-test" (Y
page 55).Problem
Possible causes/consequences and
M
MSolutions The PASSENGER AIR
BAG OFF indicator
lamp lights up and
remains lit, even
though the front-
passenger seat is occu-
pied by an adult or a
person with a build cor-responding to that of an
adult. The classification of the person on the front-passenger seat is
incorrect.
X Make sure the conditions for a correct classification of the per-
son on the front-passenger seat are met (Y page 52).
X If the PASSENGER AIR BAG OFF indicator lamp remains lit, the
front-passenger seat may not be used.
X Have the automatic front-passenger front airbag deactivation
system checked as soon as possible at a Mercedes-Benz Ser-
vice Centre. The PASSENGER AIR
BAG OFF indicator
lamp does not light up
and/or does not stay
on.
The front-passenger
seat is:
R empty
R occupied with a rear-
ward-facing child
restraint system The automatic front-passenger front airbag deactivation system is
malfunctioning.
X Make sure there is nothing between the seat and the child
restraint system.
X Make sure that the entire base of the child restraint system rests
on the seat cushion of the front-passenger seat.
X Make sure that the seat cushion length is fully retracted.
X When installing the child restraint system, make sure that the
seat belt is tight. Do not pull the seat belt tight with the front-
passenger seat adjustment. This could result in the seat belt and the child restraint system being pulled too tightly.
X Check that the child restraint system is installed correctly.
X Make sure that no objects are applying additional weight to the
seat.
X If the PASSENGER AIR BAG OFF indicator lamp remains off and/
or the PASSENGER AIR BAG ON indicator lamp lights up, do not
install a rearward-facing child restraint system on the front-
passenger seat. It is recommended that you fit the child
restraint system to a suitable rear seat.
X Have the automatic front-passenger front airbag deactivation
system checked as soon as possible at a Mercedes-Benz Ser-
vice Centre. 56
Occupant safetySafety
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 or if the vehicle overturns, the
applicable components of the restraint sys-
tem are activated independently of each
other depending on the apparent type of acci-
dent.
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
R Windowbags on the driver's and front-
passenger side in certain situations if the
vehicle overturns and if the system deter-
mines that deployment can offer additional
protection to that provided by the seat belt
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
R overturn PRE-SAFE
®
(anticipatory occupant
protection)
Introduction In certain hazardous situations, PRE-SAFE
®
takes pre-emptive measures to protect the
vehicle occupants. 58
Occupant safetySafety
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 a PRE-
SAFE ®
system, 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 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 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 side windows are
closed so that only a small gap remains.
R the front-passenger seat is adjusted if it is
in an unfavourable position.
R vehicles with a multicontour seat: the air
pressure in the side bolsters of the back-
rest is increased.
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
bolsters is reduced again. 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). PRE-SAFE
®
PLUS (anticipatory occu-
pant protection PLUS)
Introduction PRE-SAFE
®
PLUS is only available in vehicles
with the Driving Assistance package.
Using the radar sensor system, PRE-SAFE ®
PLUS is able to detect that a head-on or rear-
end collision is imminent. In certain hazard-
ous situations, PRE-SAFE ®
PLUS takes pre-
emptive measures to protect the vehicle
occupants.
Important safety notes The intervention of PRE-SAFE
®
PLUS cannot
prevent an imminent collision.
The driver is not warned when PRE-SAFE ®
PLUS intervenes.
PRE-SAFE ®
PLUS does not intervene when
reversing.
When driving, or when parking or exiting a
parking space with assistance from Active
Parking Assist, PRE-SAFE ®
PLUS will not
apply the brakes.
Function PRE-SAFE
®
PLUS intervenes in certain situa-
tions if the radar sensor system detects an
imminent head-on or rear-end collision. Occupant safety
59Safety Z
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 tyres and the
road surface. Please pay special attention to
the notes on tyres, recommended minimum
tyre tread depths etc. (Y page 376).
In wintry driving conditions, always use winter
tyres (M+S tyres) 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 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 69). 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 305) and
display messages which may be shown in the
instrument cluster (Y page 267).
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. 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 69). 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. 70
Driving safety systemsSafety
i
Pay attention to the important safety
notes in the "Driving safety systems" sec-
tion (Y page 69).
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.
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 78).
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 78
Driving safety systemsSafety
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
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 260).
If the PRE-SAFE ®
Brake is not activated, the
æ symbol appears in the multifunction
display.
This function will issue a warning if:
R at a speed of around 30 km/h or 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 collision,
preventive passenger protection measures
(PRE-SAFE ®
) are activated.
If the risk of 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 Driving safety systems
79Safety Z
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/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 262). 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 Exterior lighting
129Lights andwindscreen wipers 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 26). Overview of climate control systems
General notes
Observe the settings recommended on the
following pages. The windows could other-
wise mist up.
To prevent the windows from misting up:
R switch off climate control only briefly
R activate air-recirculation mode only briefly
R activate the "Cooling with air dehumidifica-
tion" function
R activate the windscreen demisting function
briefly, if required
Climate control regulates the temperature
and air humidity in the vehicle interior. The air
filter cleans the air, thus improving the inte-
rior climate.
The "Cooling with air dehumidification" func-
tion is only available when the engine is run-
ning. Optimum climate control is only ach-
ieved with the side windows and roof closed.
The residual heat function can only be acti-
vated or deactivated with the ignition
switched off (Y page 147).
i Ventilate the vehicle for a brief period
during warm weather, e.g. using the con-
venience opening feature (Y page 100).
This will speed up the cooling process and
the desired interior temperature will be
reached more quickly. i
The integrated filter filters out most par-
ticles of dust and soot and completely fil-
ters out pollen. It also reduces gaseous pol-
lutants and odours. A clogged filter reduces the amount of air supplied to the vehicle
interior. For this reason, you should alwaysobserve the interval for replacing the filter,
which is specified in the Service Booklet. As this depends on environmental conditions,
e.g. heavy air pollution, the interval may be shorter than stated in the Service Booklet.
i It is possible that the blower may be acti-
vated automatically 60 minutes after the
key has been removed depending on vari-
ous factors, e.g. the outside temperature.
The vehicle is then ventilated for
30 minutes to dry the automatic climate
control. 138
Overview of climate control systemsClimate control