MERCEDES-BENZ GL 2012 Workshop Manual

Problems with the occupant classification systemProblemPossible causes/consequences and M SolutionsThe 42
indicator lamp
illuminates and
remains illuminated.
The person on the
front-passenger seat:
R has the weight of a
typical adult
R has been determined
by the system not to
be a child.The OCS is malfunctioning.XHave the OCS checked as soon as possible at an authorized
Mercedes-Benz Center.XObserve the additional display messages in the multifunction
display ( Y page 239).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 SolutionsThe 42
indicator lamp does not
illuminate and/or does
not remain illuminated.
The front-passenger
seat is:
R unoccupied
R occupied with a
weight up to or less
than a typical 12-
month-old child in a
standard child
restraint systemThe OCS is malfunctioning.XMake sure there is nothing between the seat cushion and the
child seat.XCheck the installation of the child restraint system.XMake sure that no objects are applying additional weight onto
the seat.XMake sure there are no objects applying additional force to the
seat. Head restraints that press against the roof or books that
are behind or trapped between the seat, for example, apply
additional force to the seat. The OCS senses such forces as
additional weight.XIf the 42 indicator lamp does not illuminate, have
the OCS checked as soon as possible at an authorized
Mercedes-Benz Center. Do not transport a child on the front-
passenger seat as long as the OCS is not functioning.XObserve the additional display messages in the multifunction
display ( Y page 239).Occupant safety49SafetyZ

GWARNING
If the 42 indicator lamp does not illuminate or remains out with the weight of a
typical 12-month-old child in a standard child restraint or less, or is unoccupied, on the front-
passenger seat, do not transport a child on the front-passenger seat until the system has been
repaired.
BabySmart™ air bag deactivation
system
How the air bag deactivation system
works
The BabySmart™ system is standard
equipment in Canada.
GWARNING
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 always secure children in the
rear seats. Regardless of the seat position,
children under 12 years must be secured
correctly in a suitable infant or child restraint
system or booster seat suitable for the size
and weight of the child.
Secure the infant restraint system or child
restraint system using:
R the seat belt of the vehicle
R the seat belt and a Top Tether belt
R the LATCH-type (ISOFIX) child seat mount
and a Top Tether belt
The child restraint system must be installed
and secured correctly, observing the
manufacturer's installation instructions.
Occupants, in particular children, must sit as
upright as possible, fasten the seat belt
correctly and use a suitable infant restraint
system, child restraint system or booster seat
suitable for the size and weight of the child.
Children can be seriously or even fatally
injured by an air bag deploying. Observe the
following important information if it is
necessary to carry a child on the front-
passenger seat:
R Canada only: children under 12 years of age
may only sit in the front-passenger seat if
they are seated in a child restraint system
which is compatible with BabySmart™ and
approved by Mercedes-Benz. When the
child restraint system is installed correctly,
the front-passenger front air bag is disabled
in conjunction with the BabySmart™
system installed in the vehicle. If the front-
passenger front air bag is deployed in the
event of a collision, it could hit the child.
This could lead to serious or fatal injuries.
R A child in a rearward-facing child restraint
system on the front-passenger seat could
be seriously injured or even killed if the
front-passenger front air bag inflates in a
collision despite the air bag technology
installed in your vehicle, which could occur
under some circumstances. The only way
to completely rule out this risk is by making
sure you never place a child in a rearward-
facing child restraint system on the front-
passenger seat. For this reason, we
strongly advise that you always carry
children in a rearward-facing child restraint
system on a rear seat.
R If it is necessary to install a BabySmart™-
compatible rear-facing child restraint
system on the front-passenger seat, make
sure the 42 indicator lamp is
illuminated. This indicates that the front-
passenger front air bag is deactivated. If the
42 indicator lamp does not
light up or goes out when the child restraint50Occupant safetySafety

system is installed, check the anchorages
of the restraint system. Periodically check
the 42 indicator lamp while
driving to make sure the 42
indicator lamp is illuminated. If the
42 indicator lamp goes out or
remains out, you may only carry a child on
the front-passenger seat once the system
has been repaired.
A child in a rearward-facing child restraint
system on the front-passenger seat can be
seriously injured or even killed if the front-
passenger front air bag is deployed.
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.
Check the 42 indicator lamp
repeatedly, every time you use a
BabySmart™-compatible child restraint
system on the front-passenger seat. Should
the 42 indicator lamp not
illuminate or go out while the restraint is
installed, please check installation. 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, the
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 SmartKey has been removed from the
ignition lock or is in position 0, indicator lamp
42 : does not light up.
Occupant safety51SafetyZ

The system does not disable:
R the side impact air bag
R the window curtain air bag
R the Emergency Tensioning Devices/belt
buckle tensioners
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. Have the BabySmart™
system checked at an authorized Mercedes-
Benz Center before transporting a child on
the front-passenger seat.
For further information, see "Problems with
air bag deactivation system" ( Y page 53).
GWARNING
Do not place powered-on laptops, mobile
phones, electronic tags such as those used in
ski passes or similar 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 42
indicator lamp not to come on during self-test.
The + SRS indicator lamp and/or the
42 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.
52Occupant safetySafety

Problems with air bag deactivation systemProblemPossible causes/consequences and M SolutionsThe 42
indicator lamp lights up
and remains
illuminated.A BabySmart™ compatible child restraint system is installed on
the front-passenger seat.
The front-passenger air bag is therefore disabled.There is no BabySmart™ compatible child restraint system
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 SolutionsThe 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 seat.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
air bag deactivation system has been repaired.PRE-SAFE ®
(preventative occupant
protection)GWARNING
The PRE-SAFE ®
system reduces the impact of
an accident on vehicle occupants, as long as
their seat belts have been fastened correctly.
Although your vehicle is equipped with a PRE-
SAFE ®
system, the possibility of injury in the
event of an accident cannot be ruled out. You
should therefore always drive carefully and
adapt your driving style to the prevailing road,
weather and traffic conditions.
PRE-SAFE ®
takes preemptive measures to
protect occupants in certain hazardous
situations.
PRE-SAFE ®
intervenes:
R in emergency braking situations when BAS
intervenes
R in critical driving situations, e.g. when
physical limits are exceed and the vehicle
understeers or oversteers severelyOccupant safety53SafetyZ

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 function for the
front-passenger seat: the front-passenger
seat is adjusted if it is in an unfavorable
position.
R if the vehicle skids, the side windows are
closed so that only a small gap remains.
R on vehicles with a 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 seat back slightly, but
only when the vehicle is stationary.
The belt pretensioning is reduced and the
locking mechanism is released.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 seat-belt
adjustment, a convenience function
integrated into PRE-SAFE ®
, can be found in
the "Seat-belt adjustment" section
( Y page 58).
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
NECK-PRO 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.
If the NECK-PRO head restraints have been
triggered in an accident, reset the NECK-PRO
head restraints on the driver’s and front-
passenger seat ( Y page 54). 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.
Resetting triggered NECK-PRO head
restraints
Important safety notes
GWARNING
For reasons of safety, have the NECK-PRO
head restraints/NECK-PRO luxury head
restraints checked at an authorized
Mercedes-Benz Center after a rear-end
collision.
GWARNING
When pushing back the NECK-PRO head
restraint cushion, make sure your fingers do
not become caught between the head
restraint cushion and the cover. Failure to
observe this could result in injuries.
NECK-PRO head restraints
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
54Occupant safetySafety

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 in the direction of arrow ; as far as
it will go.XFirmly push the NECK-PRO head restraint
cushion back in the direction of arrow =
until the cushion engages.XRepeat this procedure for the second
NECK-PRO head restraint.
NECK-PRO luxury head restraints
i If you have difficulty resetting the NECK-
PRO luxury head restraints, have this work
carried out at a qualified specialist
workshop, e.g. an authorized Mercedes-
Benz Center.
XRemove resetting tool : from the vehicle
document wallet.XSlide resetting tool : into guide ;
between the NECK-PRO luxury head
restraint and the rear cover of the head
restraint.XPush resetting tool : downwards until you
hear the head restraint deployment
mechanism engage.XPull out resetting tool :.XFirmly press the NECK-PRO luxury head
restraint cushion back = until it engages.XRepeat this procedure for the second
NECK-PRO luxury head restraint.XPut resetting tool : back into the vehicle
document wallet.
Seat belts
Important safety notes
The use of seat belts and infant and child
restraint systems is required by law in all 50
states, the District of Columbia, the U.S.
territories and all Canadian provinces.
Even where this is not the case, all vehicle
occupants should have their seat belts
fastened when the vehicle is in motion.
i For further information on infants and
children traveling in the vehicle and on
infant and child restraint systems, see
"Children in the vehicle" ( Y page 61).
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
Occupant safety55SafetyZ

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
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 beltsGWARNING
USE SEAT BELTS PROPERLY
R Seat belts can only work 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 the
event 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 front air bag, driver's side knee
bag, front-passenger front air bag, side
impact air bags, window curtain air bags for
the side 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,
driver's side knee bag 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 off 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
56Occupant safetySafety

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 fitted
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.
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 beltsGWARNING
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 correctly. 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 will be struck by the air bag.
If this happens, serious or fatal injury will
result.
Occupant safety57SafetyZ

XAdjust the seat and move the backrest to
an almost vertical position ( Y page 98).XPull the seat belt smoothly through belt
sash guide :.XWithout twisting it, guide the shoulder
section of the seat belt across the middle
of your shoulder and the lap section across
your 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 58).XIf necessary, adjust the seat belt to the
appropriate height ( Y page 58).XIf necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
All seat belts except the driver's seat belt are
equipped with a special seat belt retractor to
securely fasten child restraint systems in the
vehicle. For further information on special
seat belt retractors, see ( Y page 63).
For more information about releasing the seat
belt with release button ?, see "Releasing
seat belts" ( Y page 59).
Seat belt adjustment
The seat-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
retraction 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 seat-belt
adjustment on and off in the on-board
computer ( Y page 228).
The seat-belt adjustment is an integral part of
the PRE-SAFE ®
convenience function. More
information about PRE-SAFE ®
can be found
in the "PRE-SAFE ®
(preventative occupant
protection)" section ( Y page 53).
Belt height adjustment
You can adjust the seat belt height on the
driver's seat and the front-passenger seat.
Adjust the height so that the upper part of the
seat belt is routed across the center of your
shoulder.
58Occupant safetySafety