2015 MERCEDES-BENZ B-CLASS HATCHBACK Owners Manual

Problems with automatic front-passenger front airbag deactivation
Be sure to observe the notes on "System self-test" (Y
page 45).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 per-
son with a build corre-
sponding to that of an
adult. The classification of the person on the front-passenger seat is false.
X Make sure the conditions for a correct classification of the person
on the front-passenger seat are met (Y page 42).
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 sys-
tem checked as soon as possible at a Mercedes-Benz Service
Centre. The PASSENGER AIR
BAG OFF indicator lamp
does not light up and/or
does not stay on.
The front-passenger seatis:
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 sys-
tem checked as soon as possible at a Mercedes-Benz Service
Centre. 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 46
Occupant safetySafety

after an accident. Take this into account, par-
ticularly if a seat belt tensioner was triggered or
an airbag was deployed.
An electric motor is used by PRE-SAFE ®
to trig-
ger the tightening of the seat belt in hazardous
situations. This procedure is reversible.
If the belt tensioners are triggered or an airbag is
deployed, you will hear a bang, and a small
amount of powder may also be released. The
6 restraint system warning lamp lights up.
Only in rare cases will the bang affect your hear-
ing. In general, the powder released is not haz-
ardous to health but may cause short-term
breathing difficulties to persons suffering from
asthma or other pulmonary conditions. Provided it is safe to do so, you should leave the vehicle
immediately or open the window in order to pre- vent breathing difficulties.
Operation During the first stage of a collision, the restraint
system control unit evaluates important physi-
cal data relating to vehicle deceleration or accel-
eration, 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 information
under: "Restraint system warning lamp"
(Y page 34)
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 collisions,
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 airbag 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 35).
Your vehicle has two-stage front airbags. In the
first deployment stage, the front airbag is 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 mil-
liseconds.
The activation threshold for the seat belt ten-
sioners and airbags is determined based on the
evaluation of the vehicle's rate of deceleration
or acceleration at various points in the vehicle.
This process is pre-emptive in nature. The trig-
gering/deployment process should take place
in good time at the start of the collision.
The rate of vehicle deceleration or acceleration
and the direction of the force are essentially
determined by:
R the distribution of forces during the collision
R the collision angle
R the deformation characteristics of the vehicle
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 deci-
sive role in the deployment of an airbag, nor do
they provide an indication of airbag deployment.
The vehicle may be deformed significantly with-out an airbag being deployed. This is the case if
only parts which are relatively easily deformed
are affected and the rate of deceleration 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 longitudinal 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 independently 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 Occupant safety
47Safety Z

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 determines
that deployment can offer additional protec-
tion for the vehicle occupants in this situation
i Not all airbags are deployed in an accident.
The different airbag systems work independ-
ently of each other.
How the airbag system works is determined
by the severity of the accident detected,
especially the vehicle deceleration or accel-
eration, and the apparent type of accident:
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 vehi- cle 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 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 physi-
cal limits are exceeded and the vehicle under- steers or oversteers severely
PRE-SAFE ®
takes the following measures
depending on the hazardous situation detected:
R the front seat belts are pre-tensioned.
R if the vehicle skids, the side windows are
closed.
R vehicles with the memory function: the front-
passenger seat is adjusted if it is in an unfav-
ourable position.
If the hazardous situation passes without result- ing 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. Informa-
tion about the convenience function can be
found under "Belt adjustment" (Y page 38). 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 drive system and high-voltage electrical
system are switched off
R vehicles with the Mercedes-Benz emergency
call system: automatic emergency call 48
Occupant safetySafety

Children in the vehicle
Important safety notes
Accident statistics show that children secured
in the rear seats are safer than children 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 protected there.
If a child younger than twelve years old and
under 1.50 m in height is travelling in the vehi-
cle:
R always secure the child in a child restraint
system suitable for Mercedes-Benz vehicles.
The child restraint system must be appropri-
ate 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 42). G
WARNING
If children are left unsupervised in the vehicle, they could:
R open doors, thereby endangering other per-
sons or road users
R get out and be struck by oncoming traffic
R operate vehicle equipment and become
trapped, for example
In addition, the children could also set the
vehicle in motion by, for example:
R releasing the parking brake
R shifting the transmission out of park posi-
tion P
R starting the vehicle's drive system
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 and animals unattended in the vehi-
cle. Keep the keys out of the reach of children. G
WARNING
If persons (particularly children) are exposed
to heat or cold for a prolonged period, there is a risk of serious or even fatal injuries. Never
leave persons (particularly children) unatten-
ded in the vehicle. G
WARNING
If the child restraint system is placed in direct sunlight, the parts could become very hot.
Children could be suffer burns by touching
these parts, in particular on the metallic parts
of the child restraint system. There is a risk of injury.
If you and your child leave the vehicle, always
make sure that the child restraint system is
not in direct sunlight. Cover it with a blanket, for example. If the child restraint system has
been exposed to direct sunlight, leave it to
cool down before securing the child in it.
Never leave children unattended in the vehi-
cle.
Always ensure that all vehicle occupants have
their seat belts fastened correctly and are sitting
properly. Particular attention must be paid to
children.
Observe the safety notes on the seat belt
(Y page 36) and the information on the correct
use of the seat belt (Y page 37). Child restraint system
If you fit a rearward-facing child restraint system
to the centre rear seat, the rear arm rest must be folded back as far as possible.
Observe the instructions for correct use of the
child restraint system (Y page 54).
For safety reasons, Mercedes-Benz recom-
mends that you only use a child restraint system
recommended by Mercedes-Benz
(Y page 58). G
WARNING
If the child restraint system is incorrectly fit-
ted on the seat position suitable for this pur-
pose, it cannot perform its intended protec-
tive function. In the event of an accident, Children in the vehicle
49Safety
Z

sharp braking or a sudden change in direction,
the child may not be held securely. There is an
increased risk of serious or even fatal injuries.
Observe the manufacturer's installation
instructions and the correct use for the child
restraint system. Make sure that the entire
surface of the child restraint system is resting
on the seat surface. Never place objects
under or behind the child restraint system,
e.g. cushions. Only use child restraint sys-
tems with the original cover designed for
them. Only replace damaged covers with gen- uine covers. G
WARNING
If the child restraint system is fitted incor-
rectly or is not secured, it can come loose in
the event of an accident, heavy braking or a
sudden change in direction. The child
restraint system could be thrown about, strik- ing vehicle occupants. There is an increased
risk of injury, possibly even fatal.
Always fit child restraint systems properly,
even if they are not being used. Make sure
that you observe the child restraint system
manufacturer's installation instructions.
You will find further information on stowing
objects, luggage and loads securely under
"Loading guidelines" (Y page 224).G
WARNING
Child restraint systems or their securing sys-
tems that have been damaged or subjected to a load in an accident cannot perform their
intended protective function. In the event of
an accident, sharp braking or a sudden
change in direction, the child may not be held securely. There is an increased risk of serious
or even fatal injuries.
Immediately replace child restraint systems
that have been damaged or subjected to a
load in an accident. Have the child restraint
securing systems checked in a qualified spe-
cialist workshop before fitting a child restraint
system again. The securing systems of child restraint systems
are:
R the seat belt system
R the ISOFIX or i-Size securing rings
R the Top Tether anchorages
If it is absolutely necessary to fit a child restraint system to the front-passenger seat, always
observe the information on "Child restraint sys-
tems on the front-passenger seat"
(Y page 52).
Observe the warning labels in the vehicle inte-
rior and on the child restraint system.
i It is advisable to use Mercedes-Benz care
products to clean child restraint systems rec- ommended by Mercedes-Benz. You can
obtain information about this at any
Mercedes-Benz Service Centre. ISOFIX and i-Size child restraint sys-
tems
G
WARNING
ISOFIX child restraint systems or i-Size child
restraint systems do not offer sufficient pro-
tection for children whose weight is greater
than 22 kg, who are secured using the safety belt integrated in the child restraint system.
The child could, for example, not be restrained
correctly in the event of an accident. This
poses an increased risk of injury or even fatal
injury.
If the child weighs more than 22 kg, only use
ISOFIX child restraint systems or i-Size 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.
When fitting a child restraint system, be sure to
observe the manufacturer's installation and
operating instructions and the instructions for
correct use of the child restraint system
(Y page 54).
Before every trip, make sure that the ISOFIX
child restraint system is engaged correctly in
both ISOFIX securing rings. 50
Children in the vehicleSafety

This symbol indicates an ISOFIX position which
is suitable for attaching an ISOFIX child restraint system. A similar symbol can be found on the
ISOFIX child restraint system. This symbol indicates an i‑Size position which is
suitable for attaching an i-Size child restraint
system. A similar symbol can be found on the i- Size child restraint system.
! When fitting the child restraint system,
make sure that the seat belt for the centre
seat does not get trapped. Otherwise, the
seat belt could be damaged. :
ISOFIX securing rings ;
i-Size securing rings
X Install the ISOFIX child restraint system on
both ISOFIX securing rings :or i-Size secur-
ing rings ;.
or
X Install the i-Size child restraint system on both
i-Size securing rings ;.
ISOFIX and i-Size are standardised securing sys-
tems for special child restraint systems. ISOFIX child restraint systems are approved in accord-
ance with ECE R-44. i-Size child restraint sys-
tems are approved in accordance with ECE
R-129.
Only child restraint systems that have been
approved in accordance with ECE R-44 may be
attached to ISOFIX securing rings. i-Size child
restraint systems that have been approved in
accordance with ECE R-44 and ECE R-129 may
be attached to i-Size securing rings. ISOFIX
securing ring :or i-Size securing ring ;are
installed on the left and right sides of the rear
seats. Top Tether
Introduction Top Tether provides an additional connection
between the child restraint system secured with
ISOFIX and the vehicle. It helps reduce the risk
of injury even further. If the child restraint sys-
tem is fitted with a Top Tether belt, this should
always be used.
Important safety notes G
WARNING
If the rear seat backrests are not locked, they
could fold forwards in the event of an acci- Children in the vehicle
51Safety
Z

dent, heavy braking or sudden changes of
direction. As a result, child restraint systems
cannot perform their intended protective
function. Rear seat backrests that are not
locked can also cause additional injuries, e.g. in the event of an accident. This poses an
increased risk of injury or even fatal injury.
Always lock rear seat backrests after fitting a Top Tether belt. Observe the lock verificationindicator. Adjust the rear seat backrests so
that they are in an upright position.
If the rear backrest is not engaged and locked,
the red lock verification indicator will be visible
(Y page 228).
Top Tether anchorages The Top Tether anchorage points are located on
the rear side of the backrests on both outer rear seats. X
Move head restraint :upwards.
X Release rear seat backrest =and fold it for-
wards (Y page 228).
X Route Top Tether belt Bunder head
restraint :between the two head restraint
bars. X
Hook Top Tether hook Aof Top Tether belt
B into Top Tether anchorage ?.
Ensure that:
R Top Tether hook Ais hooked into Top
Tether anchorage ?as shown
R Top Tether belt Bis not twisted
R Top Tether belt Bis routed between rear
seat backrest =and luggage compart-
ment cover ;if luggage compartment
cover ;is fitted
R Top Tether belt Bis routed between the
rear seat backrest =and the safety net if
the safety net is fitted
X Swing back rear seat backrest =until it
engages.
The red lock verification indicator is no longer visible.
X Fit the ISOFIX child restraint system with Top
Tether. Always comply with the child restraint
system manufacturer's installation instruc-
tions when doing so.
X Tension Top Tether belt B. Always comply
with the child restraint system manufactur-
er's installation instructions when doing so.
X If necessary, move head restraint :back
down again slightly (Y page 89). Make sure
that you do not interfere with the correct rout-
ing of Top Tether belt B. Child restraint system on the front-
passenger seat
General notes Accident statistics show that children secured
in the rear seats are safer than children secured
in the front-passenger seat. For this reason,
Mercedes-Benz strongly advises that you install a child restraint system on a rear seat.
Vehicles with the automatic front-passenger
front airbag deactivation system: if it is abso-
lutely necessary to fit a child restraint system tothe front-passenger seat, always observe the
information on the "Automatic front-passenger
front airbag deactivation system" (Y page 42).52
Children in the vehicleSafety

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 airbag 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 illustration. 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 enabled
(Y page 35). 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 indica-
ted 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 function and
do not indicate that there is an automatic front-
passenger front airbag deactivation system.
Always fit the rearward-facing restraint system
to a suitable rear seat in this case (Y page 54).
Observe the following information under "Rear-
ward-facing child restraint system" and
"Forward-facing child restraint system" as well
as information on the suitable positioning of the child restraint system (Y page 54).
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 lamp is
lit continuously (Y page 35)is the front-
passenger front airbag disabled.
Always observe the information on suitable
positioning of the child restraint system
(Y page 54) in addition to the child restraint
system manufacturer's installation and operat-
ing instructions. Children in the vehicle
53Safety Z