MERCEDES-BENZ M-Class 2011 W164 Workshop Manual

carry a child on the front-passenger seat
once the system has been repaired.
A child in a rear-facing child restraint on the
passenger seat will be seriously injured or
even killed if the passenger front air bag
inflates.
R when securing a child in a front-facing child
restraint system on the front-passenger
seat, you must:
- move the front-passenger seat as far
back as possible
- use a child restraint system that is
suitable for the age, size and weight of
the child
- observe the manufacturer's installation
instructions in order to install and secure
the child restraint system correctly.GWarning
When using a BabySmart™-compatible child
restraint system on the front-passenger seat,
the front-passenger front air bag is only
disabled if the 42 indicator lamp
is illuminated.
Always check the 42 indicator
lamp if you are using a BabySmart™-
compatible child restraint system on the
front-passenger seat. If the 42
indicator lamp does not light up or goes out
when the child restraint system is installed,
check the anchorages of the restraint system.
If the 42 indicator lamp remains
out, do not use the BabySmart™ child
restraint system to carry a child on the front-
passenger seat until the system has been
repaired.
GWarning
The BabySmart™ air bag disabling system
ONLY works with specially adapted child
restraint systems. It does not work with child
restraint systems that are not compatible with
BabySmart™.
Never place anything between the seat
cushion and the child restraint system (e.g. a
cushion), as this reduces the effectiveness of
the BabySmart™ air bag deactivation system.
The underside of the child restraint system
must lie against the seat cushion of the front-
passenger seat. In the event of an accident,
an incorrectly installed child restraint system
could injure the child instead of offering
protection.
Observe the manufacturer's instructions
when installing special child restraint
systems.
Special child restraint systems which are
compatible with BabySmart™ are necessary
for deactivating the front-passenger front air
bag. When the special child restraint system
which is compatible with BabySmart™ is
installed correctly and is recognized by the
sensor system in the front-passenger seat,
the front-passenger front air bag is
deactivated. In this case, 42
indicator lamp : illuminates. If you have any
questions regarding the special child
restraint systems which are compatible with
BabySmart™, consult an authorized
Mercedes-Benz Center.
If the key has been removed from the ignition
lock or is in position 0, indicator lamp
42 : does not light up.
The system does not disable:
R the side impact air bag
R the window curtain air bag
R the Emergency Tensioning Device/belt
buckle tensioner (ETD)
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System self-test
The 42 indicator lamp
illuminates when you:
R turn the SmartKey to position 1 or 2 in the
ignition lock
R on vehicles with KEYLESS-GO, press the
Start-Stop button once or twice.
The 42 indicator lamp goes out
again after approximately six seconds.
If the 42 indicator lamp does not
illuminate or is lit continuously, the system is
malfunctioning. Before transporting a child
on the front-passenger seat, have the
BabySmart™ system checked at an
authorized Mercedes-Benz Center.
For more information, see "Problems with the
air bag deactivation system" section
( Y page 51)
GWarning!
Do not place powered-on laptops, mobile
phones, electronic tags such as those used in
ski passes and like electronic devices on the
front passenger seat. Signals from such
devices may interfere with the BabySmart™
air bag deactivation system. Such signal
interference may cause the 4 2
indicator lamp not to come on during self-test.
The SRS indicator lamp + and/or the
4 2 indicator lamp could be
continuously lit, indicating that the system is
not functioning. The front passenger front air
bag could deploy inadvertently or fail to
deploy in an accident.
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Problems with the air bag deactivation systemProblemPossible causes/consequences and M SolutionsCanada only: The
42
indicator lamp is
illuminated constantly.A special BabySmart™ compatible child restraint system is
installed on the front-passenger seat.
The front-passenger front air bag is thus deactivated.A BabySmart™-compatible child restraint system is not installed
on the front-passenger seat. The BabySmart™ system is
malfunctioning.XHave the BabySmart™ system checked as soon as possible at
an authorized Mercedes-Benz Center.GWarning
If the 42 indicator lamp illuminates and remains illuminated when the weight of a
typical adult or someone larger than a small individual has been detected on the passenger seat,
the system then determines the occupant cannot be a child. Do not allow any occupant to use
the passenger seat until the system has been repaired.
ProblemPossible causes/consequences and M SolutionsCanada only: The
42
indicator lamp does not
illuminate or does not
remain illuminated with
a BabySmart™
compatible child
restraint system
properly installed on
the front-passenger
seat.The BabySmart™ system is malfunctioning.XMake sure there is nothing between the seat cushion and the
child restraint system.XCheck the installation of the child restraint system.XIf the 42 indicator lamp does not illuminate, have
the BabySmart™ system checked as soon as possible at an
authorized Mercedes-Benz Center.
Do not transport a child on the front-passenger seat until the
BabySmart™ system has been repaired.PRE-SAFE ®
systemGWarning!
The PRE-SAFE ®
system is intended to reduce
the effects of an accident on vehicle
occupants who are wearing their seat belt
properly. Despite your vehicle being equipped
with the PRE-SAFE ®
system, the possibility of
personal injuries occurring as a result of an
accident cannot be eliminated. Therefore,
always drive carefully and adjust your driving
to the prevailing road, weather, and traffic
conditions.
PRE-SAFE ®
takes pre-emptive measures to
protect you in certain hazardous situations.
PRE-SAFE ®
intervenes:
R in emergency braking situations, if the BAS
Brake Assist System intervenes
R in critical driving situations, e.g. if the
vehicle understeers or oversteers severely
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of having to swerve to avoid an obstacle at
a speed above 85 mph (140 km/h).
PRE-SAFE ®
takes the following measures
depending on the hazardous situation
detected:
R the front seat belts are pre-tensioned.
R on vehicles with memory functions: the
front-passenger seat is adjusted if it is in an
unfavorable position under accident
conditions.
R if the vehicle skids, the side windows are
closed so that only a small gap remains.
R on vehicles with sliding sunroof: if the
vehicle skids, the sliding sunroof closes so
that only a small gap remains.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pretensioning. All settings made by
PRE-SAFE ®
can then be reversed.
If the seat belts are not released:XMove the backrest or the seat back slightly
until the belt pretensioning is reduced.
The locking mechanism releases.GWarning
Make sure that nobody can become trapped
as you adjust the seat.
! Make sure that there are no objects in the
footwell or behind the seats when resetting
the seats. There is a risk that the seats
and/or the objects could be damaged.
More information about belt adjustment, a
convenience function integrated into PRE-
SAFE ®
, can be found in the "Belt adjustment"
section ( Y page 56).
NECK-PRO head restraints
The NECK-PRO head restraints increase
protection to the driver's and front-
passenger's head and neck. To this end, the
head restraints on the driver's and front-
passenger seats are moved forwards and
upwards in the event of a rear-end collision of
a certain severity. This provides better head
support.GWarning
Do not secure any objects (e.g. coat hangers)
on the NECK-PRO head restraints. Otherwise,
the NECK-PRO head restraints may not
function properly, or in the event of a rear-end
collision may not be able offer the level of
protection they are designed to provide.
GWarning
Only use seat covers/head restraint covers
that have been tested and approved by
Mercedes-Benz for your model.
Using seat covers and head restraint covers
other than those recommended can prevent/
impair the triggering of NECK-PRO head
restraints and/or the deployment of side
impact air bags in the front.
Contact an authorized Mercedes-Benz Center
for availability.
If the NECK-PRO head restraints have been
triggered in an accident, you must reset the
NECK-PRO head restraints on the driver’s and
front-passenger seat ( Y page 53).
Otherwise, the additional protection will not
be available in the event of another rear-end
collision. You can recognize when NECK-PRO
head restraints have been triggered by the
fact that they have moved forwards and can
no longer be adjusted.
GWarning!
For your protection, drive only with properly
positioned head restraints.
Adjust the head restraint so that it is as close
to the head as possible and the center of the
head restraint supports the back of the head
at eye level. This will reduce the potential for
injury to the head and neck in the event of an
accident or similar situation.
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Resetting triggered NECK-PRO head
restraintsGWarning!
For reasons of safety, have the NECK-PRO
head restraints checked after a rear end
collision at an authorized Mercedes-Benz
Center.
GWarning
If you press the NECK-PRO head restraint
cushion backwards, make sure that your
fingers are not trapped between the cushion
and the cover. Failure to observe could result
in injuries.
i Resetting the NECK-PRO head restraints
requires a lot of strength. If you have
difficulty resetting the NECK-PRO head
restraints, have this work carried out at a
qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center.
XTilt the top of the NECK-PRO head restraint
cushion forwards in the direction of
arrow :.XPush the NECK-PRO head restraint cushion
down as far as it will go in the direction of
arrow ;.XFirmly push the NECK-PRO head restraint
cushion backwards in the direction of
arrow = until it engages.XRepeat this procedure for the second
NECK-PRO head restraint.Seat belts
Important safety guidelines
The use of infant or child restraint systems is
required by law in all 50 states, the District of
Columbia, the U.S. territories and all
Canadian provinces.
Even if this is not the case, all vehicle
occupants should have their seat belts
fastened when the vehicle is in motion.
i See "Children in the vehicle"
( Y page 58) for further information on
infants and children traveling in the vehicle
as well as on child restraint systems.
GWarning!
Always fasten your seat belt before driving off.
Always make sure all of your passengers are
properly restrained. You and your passengers
should always wear seat belts.
Failure to wear and properly fasten and
position your seat belt greatly increases your
risk of injuries and their likely severity in an
accident.
If you are ever in an accident, your injuries can
be considerably more severe without your
seat belt properly buckled. Without your seat
belt buckled, you are much more likely to hit
the interior of the vehicle or be ejected from
it. You can be seriously injured or killed.
In the same crash, the possibility of injury or
death is lessened if you are properly wearing
your seat belt. The air bags can only protect
as intended if the occupants are properly
wearing their seat belts.
GWarning
Never ride in a moving vehicle with the seat
backrest in an excessively reclined position as
this can be dangerous. You could slide under
the seat belt in a collision. If you slide under
it, the seat belt would apply force at the
abdomen or neck. That could cause serious
or even fatal injuries. The seat backrest and
seat belt provide the best restraint when the
wearer is in a position that is as upright as
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possible and the seat belt is properly
positioned on the body.GWarning
Never let more people ride in the vehicle than
there are seat belts available. Make sure
everyone riding in the vehicle is correctly
restrained with a separate seat belt. Never
use a seat belt for more than one person at a
time.
GWarning
Damaged seat belts or seat belts that have
been subjected to stress in an accident must
be replaced and their anchoring points must
also be checked.
Only use seat belts which have been approved
by Mercedes-Benz.
Do not make any modifications to the seat
belts. This can lead to unintended activation
of the ETDs or to their failure to activate when
necessary.
Do not bleach or dye seat belts as this may
severely weaken them. In a crash they may
not be able to provide adequate protection.
Have all work carried out only by qualified
technicians. Contact an authorized
Mercedes-Benz Center.
Correct use of the seat belt
GWarning
USE SEAT BELTS PROPERLY
R Seat belts can only protect when used
properly. Never wear seat belts in any other
way than as described in this section, as
that could result in serious injuries in case
of an accident.
R Each occupant should wear their seat belt
at all times, because seat belts help reduce
the likelihood of and potential severity of
injuries in accidents, including rollovers.
The integrated restraint system includes
SRS (driver's front air bag, front-passenger
front air bag, side impact air bags, window
curtain air bags for door windows),
Emergency Tensioning Devices, seat belt
force limiters, and front seat knee bolsters.
The system is designed to enhance the
protection offered to properly belted
occupants in certain frontal (front air bags
and ETDs) and side (side impact air bags,
window curtain air bags, and ETDs) impacts
which exceed preset deployment
thresholds and in certain rollovers (window
curtain air bags and ETDs).
R Never wear the shoulder belt under your
arm, across your neck or not routed across
your shoulder. In a frontal crash, your body
would move too far forward. That would
increase the chance of head and neck
injuries. The seat belt would also apply too
much force to the ribs or abdomen, which
could severely injure internal organs such
as your liver or spleen.
Adjust the seat belt so that the shoulder
section is located as close as possible to
the middle of the shoulder. It should not
touch the neck. Never pass the shoulder
portion of the seat belt under your arm. For
this purpose, you can adjust the height of
the seat belt outlet.
R Position the lap belt as low as possible on
your hips and not across the abdomen. If
the lap belt is positioned across your
abdomen, it could cause serious injuries in
a crash.
R Never wear seat belts over rigid or
breakable objects in or on your clothing,
such as eyeglasses, pens, keys etc., as
these might cause injuries.
R Make sure the seat belt is always routed
snugly. Take special care of this when
wearing loose clothing.
R Never use a seat belt for more than one
person at a time. Do not fasten a seat belt
around a person and another person or
other objects at the same time.
R Seat belts should not be worn twisted. In a
crash, you would not have the full width of
the seat belt to distribute impact forces.54Occupant safetySafety
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The twisted seat belt against your body
could cause injuries.
R Pregnant women should also always use a
lap-shoulder belt. The lap belt portion
should be positioned as low as possible on
the hips to avoid any possible pressure on
the abdomen.
R Place the seat backrest in a position that is
as upright as possible.
R Check your seat belt during travel to make
sure it is properly positioned.
R Never place your feet on the instrument
panel, dashboard, or on the seat. Always
keep both feet on the floor in front of the
seat.
R When using a seat belt to secure infant
restraints, toddler restraints, or children in
booster seats, always follow the child seat
manufacturer's instructions.GWarning
Do not pass seat belts over sharp edges. They
could tear.
Do not allow the seat belt to get caught in the
door or in the seat adjustment mechanism.
This could damage the seat belt.
Never attempt to make modifications to seat
belts. This could impair the effectiveness of
the seat belts.
Fastening seat belts
GWarning
According to accident statistics, children are
safer when properly restrained on the rear
seats than on the front-passenger seat. Thus,
we strongly recommend that children be
placed in the rear seat whenever possible.
Regardless of seating position, children 12
years old and under must be seated and
properly secured in an appropriately sized
child restraint system or booster seat
recommended for the size and weight of the
child. For additional information, see the
"Children in the vehicle" section.
A child's risk of serious or fatal injuries is
significantly increased if the child restraints
are not properly secured in the vehicle and/
or the child is not properly secured in the child
restraint.GWarning
Canada only: children 12 years old and under
may ride on the front seat if a BabySmart™
compatible child restraint system is installed
on the front-passenger seat. Use only
Mercedes-Benz approved BabySmart™
compatible child restraint systems. A
BabySmart™ compatible child restraint
system will deactivate the front-passenger
front air bag when installed properly. The
front-passenger front air bag will not be
deactivated if the child restraint systems that
are installed are not BabySmart™ compatible
or if BabySmart™ compatible child restraint
systems are not installed correctly. If the
front-passenger front air bag is deployed in a
collision, the child could be struck by the air
bag. This could lead to serious or fatal injury.
XAdjust the seat and move the backrest to
an almost vertical position ( Y page 92).XPull the seat belt smoothly through belt
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XWithout twisting it, place the shoulder
section of the seat belt over the center of
the shoulder and the lap section across the
hips.XEngage belt tongue ; in buckle =.
Seat belt adjustment: if necessary, the
driver's and front-passenger seat belts
automatically adjust to the upper body
( Y page 56).XIf necessary, adjust the seat belt to the
appropriate height ( Y page 56).XIf necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
All seat belts in the vehicle, except the
driver's seat belt, are equipped with a special
seat belt retractor to secure child restraint
systems properly. For further information on
"Special seat belt retractors", see
( Y page 61).
For more information about releasing the seat
belt with release button ?, see "Releasing
seat belts" ( Y page 56).
Seat belt adjustment
The belt adjustment function adjusts the
driver's and front-passenger seat belt to the
upper body of the occupants. The belt strap
is tightened slightly when:
R you engage the belt tongue in the belt
buckle and you then turn the SmartKey to
position 2 in the ignition lock.
R the SmartKey is in position 2 in the ignition
lock and you then engage the belt tongue
in the buckle.
The seat-belt adjustment will apply a certain
tightening force if any slack is detected
between the occupant and the seat belt. Do
not hold on to the seat belt tightly while it is
adjusting. You can switch the belt adjustment
on and off in the on-board computer
( Y page 218).
Seat belt outlet height adjustment
You can adjust the seat belt height on the
driver's seat and the front-passenger seat.
Adjust the belt to a height that allows the
upper part of the seat belt to be routed across
the center of your shoulder.
XTo raise: slide the belt sash guide upwards.
The belt sash guide engages in various
positions.XTo lower: press and hold belt sash guide
release :.XSlide the belt sash guide downwards.XRelease belt sash guide release : and
make sure that the belt sash guide has
engaged.
Releasing seat belts
XPress release button ?(Y page 55) and
guide belt tongue ;(Y page 55) back
towards belt sash guide :(Y page 55).
!
Make sure that the seat belt is fully rolled
up. Otherwise, the seat belt or belt tongue
will be trapped in the door or in the seat
mechanism. This could damage the door,
the door trim panel and the seat belt.
Damaged seat belts can no longer fulfill
their protective function and must be
replaced. Consult an authorized Mercedes-
Benz Center.
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Belt warning for driver and front
passenger
Regardless of whether the driver's and front-
passenger seat belts have already been
fastened, the 7 seat belt warning lamp
lights up for six seconds each time the engine
is started. It then goes out once the driver and
the front passenger have fastened their seat
belts.
If the driver's seat belt is not fastened after
the engine is started, an additional warning
tone will sound. The warning tone goes out
after approximately six seconds or once the
driver's seat belt is fastened.
If after six seconds the driver or front-
passenger have not fastened their seat belts
and the doors are closed:
R the 7 seat belt warning lamp remains
illuminated as long as either the driver's or
front-passenger seat belt is not fastened.
R if the vehicle speed once exceeds 15 mph
(25 km/h), the 7 seat belt warning
lamp lights up. Additionally, a warning tone
will sound with increasing intensity for a
maximum of 60 seconds or until the
driver's and front-passenger seat belt are
fastened.
If the driver/front passenger unfasten their
seat belt while the vehicle is in motion, the
7 seat belt warning lamp lights up and a
warning tone sounds again.
The warning tone ceases even if the driver or
front passenger have still not fastened their
seat belt after 60 seconds. The 7 seat belt
warning lamp stops flashing but continues to
be illuminated.
After the vehicle has come to a standstill, the
warning tone is reactivated and the 7 seat
belt warning lamp flashes again if the vehicle
speed has exceeded 15 mph (25 km/h).
The 7 seat belt warning lamp only goes
out if:
R both the driver and the front passenger
have fastened their seat belts
or
R the vehicle is stationary and a door is open
i For more information on the 7 seat
belt warning lamp, see "Indicator and
warning lamps in the instrument cluster,
seat belt" ( Y page 248).
Emergency Tensioning Devices and
seat belt force limiters
The front seat belts and the outer seat belts
in the rear are equipped with ETDs and belt
force limiters. In addition, the front seat belts
are installed with belt buckle tensioners.
! If the front-passenger seat is not
occupied, do not engage the seat belt
tongue in the buckle on the front-
passenger seat. Otherwise, the Emergency
Tensioning Device/belt buckle tensioner
could be triggered in the event of an
accident.
ETDs/belt buckle tensioners tighten the seat
belts in an accident, pulling them close
against the body.
ETDs/belt buckle tensioners do not correct
incorrect seat positions or incorrectly
fastened seat belts.
ETDs do not pull vehicle occupants back
towards the backrest.
Seat belt force limiters, when activated, are
employed to help reduce the force exerted by
the seat belts on occupants during a crash.
The front belt force limiters are synchronized
with the front air bags, which take on a part
of the deceleration force. Thus, the force
exerted on the occupant is distributed over a
greater area.
The ETDs/belt buckle tensioners can only be
activated when:
R the ignition is switched on
R the restraint systems are operational; see
"SRS warning lamp" ( Y page 36)
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Rthe belt tongue is engaged in the buckle on
each of the three-point seat belts in the
front
R the front-passenger seat is occupied and
the belt tongue is engaged in the buckle on
the front-passenger side.
The ETDs on the outside seats in the rear
compartment are triggered independently of
the lock status of the seat belts.
The ETDs are triggered depending on the type
and severity of an accident:
R in the event of a head-on or rear-end
collision if the vehicle decelerates or
accelerates rapidly in a longitudinal
direction during the initial stages of the
impact
R in the event of a side impact, on the side
opposite the impact if the vehicle
decelerates or accelerates rapidly in a
lateral direction
R in certain situations if the vehicle overturns
and the system determines that it can
provide additional protection.
If the ETDs/belt buckle tensioners are
triggered, you will hear a bang and a small
amount of powder may also be released. Only
in rare cases will the bang affect your hearing.
The powder that is released generally does
not constitute a health hazard. The + SRS
warning lamp lights up.
i If the belt buckle tensioners have been
triggered on the front seats, the buckle will
be pulled down and will be almost flush with
the upper edge of the seat. The + SRS
warning lamp is lit.GWarning
The belt buckle tensioners on the front seats
only function if the belt buckles can be pulled
down unobstructed. They must not be
restricted in any way. Therefore, do not grab
the belt buckles and do not place any objects
under the belt buckles. Otherwise, the
tensioning of the belt by the buckle is
restricted or will not function, and will not
provide any additional protection.
GWarning
Pyrotechnical ETDs/belt buckle tensioners
that were activated must be replaced.
For your safety, when disposing of the
pyrotechnic ETDs/belt buckle tensioners
always follow our safety instructions. These
instructions are available from any authorized
Mercedes-Benz Center.
The PRE-SAFE ®
system is equipped with
electrically reversible pre-tensioners that do
not need replacing after deployment.
Children in the vehicle
Important safety guidelines
GWarning
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unattended in the
vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. The children
could:
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
ignition lock or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and the child could be burned on these
parts.
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