2014 MERCEDES-BENZ M-Class ECU

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: (Y page 28).Panic alarm
X
To activate: press000Dbutton 0002for at
least one second.
An alarm sounds and the exterior lighting
flashes.
X To deactivate: press000Dbutton 0002
again.
or
X Insert the SmartKey into the ignition lock.
or
X Press the KEYLESS-GO Start/Stop button.
The KEYLESS-GO key must be in the
vehicle. Occupant safety
Important safety notes
G
WARNING
Modifications to the restraint systems could
result in them not functioning properly any
more. The restraint systems could then no
longer protect vehicle occupants as they are
designed to do and could fail in the even tof
an accident or activate unexpectedly, for
example. There is an increased risk of injury.
Never modify parts of the restraint systems.
Do no tattemp tto modify the wiring as well as
electronic components or their software.
If it is necessary to modify an air bag system
to accommodate a person with disabilities,
contact an authorized Mercedes-Benz center.
USA only: for further information contact our
Customer Assistance Center at
1-800-FOR-MERCedes (1800-367-6372).
In this section, you will learn the most
important facts about the restraint system
components of the vehicle.
The restraint system consists of:
R seat belts
R child restraint systems
R LATCH-type (ISOFIX) child seat securing
system
Additional protection is provided by:
R SRS (Supplemental Restraint System)
R PRE-SAFE ®
R Air bag system components with:
-PASSENGER AIR BAG OFF indicator lamp
- front-passenger seat with Occupant
Classification System (OCS)
Although the systems are independent, their
protective functions work in conjunction with
each other. Not all air bags are always
deployed in an accident.
i For information on infants and children
traveling with you in the vehicle restraint
systems for infants and children, see
"Children in the vehicle" (Y page 60).42
Occupant safetySafety

Occupant Classification System
(OCS)
Method of operation G
WARNING
If the 001A001C indicator lamp illuminates
when an adult or someone larger than a small
individual is in the fron tpassenger seat, have
the fron tpassenger reposition himself or
herself in the seat until the 001A001C
indicator lamp goes out.
In the event of a collision, the air bag control
unit will no tallow front passenger front air bag
deploymen twhen the OCS has classified the
front passenger seat occupant as weighing as
much as or less than a typical 12-month-old
child in a standard child restraint or if the front
passenger seat is classified as being empty.
When the OCS senses that the front
passenger seat occupant is classified as
being up to or less than the weight of a typical
12-month-old child in a standard child
restraint, the 001A001Cindicator lamp will
illuminate when the engine is started and
remain illuminated. This indicates that the
front passenger front air bag is deactivated.
When the OCS senses that the front
passenger seat is classified as being empty,
the 001A001C indicator lamp will illuminate
when the engine is started and remain
illuminated. This indicates that the front
passenger front air bag is deactivated.
When the OCS senses that the front
passenger seat occupant is classified as
being heavier than the weight of a typical 12-
month-old child seated in astandard child
restraint or as being a small individual (such
as a young teenager or asmall adult), the
001A001C indicator lamp will illuminate for
approximately 6seconds when the engine is
started. Depending on occupant weight
sensor readings from the seat, it will then
remain illuminated or go out. With the
001A001C indicator lamp illuminated, the
fron tpassenger fron tair bag is deactivated. With the
001A001C indicator lamp out, the
front passenger front air bag is activated.
When the OCS senses that the front
passenger seat occupant is classified as an
adult or someone larger than a small
individual, the 001A001Cindicator lamp will
illuminate for approximately six seconds
when the engine is started and the ngo out.
This indicates that the front passenger front
air bag is activated.
If the 001A001C indicator lamp is illuminated,
the front passenger front air bag is
deactivated and will not be deployed.
If the 001A001C indicator lamp is not
illuminated, the front passenger front air bag
is activated and will be deployed
R in the event of certain frontal impacts
R if the impact exceeds a predetermined
triggering threshold
R independent of the side impact air bag or
pelvis air bag
If the front passenger front air bag is
deployed, the rate of inflation will be
influenced by
R the rate of vehicle deceleration as assessed
by the air bag control unit
R the front passenger's weight category as
identified by the OCS G
WARNING
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 seats whenever possible.
Regardless of seating position, children 12
years old and under must be seated and
properly secured in an appropriate infant
restraint, toddler restraint, or booster seat
recommended for the size and weight of the
child.
The infant or child restraint must be properly
secured with the vehicle's seat belt, the seat
belt and Top Tether strap, or lower anchors Occupant safety
49Safety
Z

and Top Tether strap, fully in accordance with
the child seat manufacturer's instructions.
Occupants, especially children, should always
sit as upright as possible, wear the seat belt
properly and use an appropriately sized infant
restraint, toddler restraint, or booste rseat
recommended for the size and weight of the
child.
Children can be killed or seriously injured by
an inflating air bag. Note the following
important information when circumstances
require you to place a child in the front-
passenger seat:
R Your vehicle is equipped with air bag
technology designed to deactivate the
front-passenger fron tair bag in your vehicle
when the system senses the weight of a
typical 12-month-old child or less along
with the weight of a standard appropriate
child restraint on the front-passenge rseat.
R Ac hild in a rear-facing child restraint on the
front-passenger seat will be seriously
injured or even killed if the front-passenger
front air bag inflates in a collision which
could occur under some circumstances,
even with the air bag technology installed
in your vehicle. The only means to eliminate
this risk completely is never to place a child
in a rear-facing child restraint in the front-
passenger seat. We therefore strongly
recommend that you always place a child
in a rear-facing child restraint on the rear
seat.
R If you install a rear-facing child restraint on
the front-passenger seat, make sure the
001A001C indicator lamp is illuminated,
indicating that the front-passenger front air
bag is deactivated. Should the 001A001C
indicator lamp not illuminate or go out while
the restraint is installed, please check
installation. Periodically check the
001A001C indicator lamp while driving to
make sure that the 001A001Cindicator
lamp is illuminated. If the 001A001C
indicator lamp goes out or remains out, do not transport a child on the front-passenger
seat until the system has been repaired.
Ac
hild in a rear-facing child restraint on the
front-passenger seat will be seriously
injured or even killed if the front-passenger
front air bag inflates.
R If you place a child in a forward-facing child
restraint on the front-passenger seat:
-move the seat as far back as possible
- use the proper child restraint
recommended for the age, size and
weight of the child
- secure child restraint with the vehicle's
seat belt according to the child seat
manufacturer's instructions
R For children larger than the typical 12-
month-old child, the front-passenger front
air bag may or may not be activated. G
WARNING
If the red 001FSRS warning lamp in the
instrument cluster and the 001A001C
indicator lamp light up simultaneously, the
OCS is malfunctioning. The front passenger
front air bag will be deactivated in this case.
Have the system checked by qualified
technicians as soon as possible. Contact an
authorized Mercedes-Ben zCenter.
Only have the seat repaired or replaced at an
authorized Mercedes-Benz Center.
In order to ensure proper operation of the air
bag system and OCS:
R Sit with the seat belt properly fastened in a
position that is as upright as possible with
your back against the seat backrest.
R When seated, a passenger should not
position him/herself in such a way as to
cause the passenger's weight to be lifted
from the seat cushion as this may result in
the OCS being unable to correctly
approximate the passenger's weight
category.
R Read and observe all warnings in this
chapter. 50
Occupant safetySafety

Problem Possible causes/consequences and
0001 Solutions
The PASSENGER AIR
BAG OFF indicator
lamp does not light up
and/or stays on.
The front-passenger
seat is:
R
unoccupied
R occupied with the
weight of a child up
to twelve months old
in a child restraint
system The OCS is malfunctioning.
X
Make sure there is nothing between the seat cushion and the
child seat.
X Make sure that the backrest and base of the child restraint
system are resting securely on the front-passenger seat. If
necessary, adjust the position of the front-passenger seat.
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
being pulled too tightly.
X Check the installation of the child restraint system.
X Make sure that no objectsa re applying additional weight onto
the seat.
X If the PASSENGER AIR BAG OFF indicator lamp remains off, have
the OCS system checked as soon as possible at a qualified
specialist workshop .Do not transport a child on the front-
passenger seat until the OCS has been repaired.
X Observe the additional display messages in the multifunction
display (Y page 293). PRE-SAFE
®
(anticipatory occupant
protection system)
Introduction PRE-SAFE
®
takes preemptive measures to
protect occupants in certain hazardous
situations.
Important safety notes !
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.
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.
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
physical limits are exceeded and the
vehicle understeers or oversteers severely
R on vehicles with DISTRONIC PLUS: if
BAS PLUS intervenes powerfully or the
radar sensor system detect sanimminent
dange rofcollision in certain situations.
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 sliding sunroof and
the side windows are closed so that only a
small gap remains. On vehicles with a
panorama roof with power tilt/sliding
panel, they are closed completely. 54
Occupant safetySafety

tha
tcould 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.N ever 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 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 distribut eimpact forces.
The twisted seat belt against yourb ody
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. G
WARNING
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. 56
Occupant safetySafety

Fastening seat belts
G
WARNING
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.
Ac hild'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. X
Adjust the seat and move the backrest to
an almost vertical position (Y page 104).
X Pull the seat belt smoothly through belt
sash guide 0002.
X Without twisting it, guide the shoulder
section of the seat belt across the middle
of your shoulder and the lap section across
your pelvis. X
Engage belt tongue 0003in buckle 0023.
Seat-belt adjustment:ifn ecessary, the
driver's and front-passenger seat belts
automatically adjust to the upper body
(Y page 57).
X If necessary, adjust the seat belt to the
appropriate height (Y page 58).
X If 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. Further information can be found
under "Special seat belt retractor"
(Y page 63).
For more information about releasing the seat
belt with release button 0022, see "Releasing
seat belts" (Y page 58).
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 2in the ignition lock.
R the SmartKey is in position 2in 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 277).
The seat-belt adjustment is an integral part of
the PRE-SAFE ®
convenience function. More
information about PRE-SAFE ®
can be found
under "PRE-SAFE ®
(preventative occupant
protection)" (Y page 54). Occupant safety
57Safety Z

Emergency Tensioning Devices can only be
activated when:
R
the ignition is switched on.
R the restraint systems ar eoperational; see
"SRS warning lamp" (Y page 43)
R the belt tongue is engaged in the buckle on
each of the lap-shoulder 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 if, in the event of a head-on or rear-end
collision, the vehicle decelerates or
accelerates rapidly in a longitudinal
direction during the initial stages of the
impact.
R if, in the event of a side impact, on the side
opposite the impact the vehicle
decelerates or accelerates rapidly in a
lateral direction.
R if, in certain situation swhere the vehicle
rolls over, the system determines that it
can provide additional protection.
If the ETDs are deployed, 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 and does not indicate that there
is a fire in the vehicle. The dust might cause
some temporary breathing difficulty for
people with asthma or other breathing
trouble. To avoid this, you may wish to get out
of the vehicle as soon as it is safe to do so.
You can also open the window to allow fresh
air to enter the vehicle interior. The 001FSRS
warning lamp lights up. Children in the vehicle
Child restraint systems
Important safety notes G
WARNING
According to accident statistics, children are
safer when properly restrained in the rear
seating positions than in the front seating
position. Thus, we strongly recommend that
children be placed in the rear seats whenever
possible. Regardless of seating position,
children 12 years old and under must be
seated and properly secured in an appropriate
infant restraint, toddler restraint, or booster
seat recommended for the size and weight of
the child.
The infant or child restraint must be properly
secured with the vehicle's seat belt, the seat
belt and top tether strap, or lower anchors and
top tether strap, fully in accordance with the
child seat manufacturer's instructions.
Occupants, especially children, should always
sit as upright as possible, wear the seat belt
properly and use an appropriately sized infant
restraint, toddler restraint, or booster seat
recommended for the size and weight of the
child.
Children can be killed or seriously injured by
an inflating air bag. Note the following
important information when circumstances
require you to place a child in the front
passenger seat:
R Your vehicle is equipped with air bag
technology designed to deactivate the front
passenger front air bag in your vehicle
when the system senses the weight of a
typical 12-month-old child or less along
with the weight of a standard appropriate
child restraint on the front passenger seat.
R For children larger than the typical
12-month-old child, the front passenger
front air bag may or may not be activated.
Always make sure the 001A001Cindicator
lamp is illuminated, indicating that the front
passenger front air bag is deactivated. 60
Children in the vehicleSafety

R
Ac hild in a rear-facing child restraint on the
front passenger seat will be seriously
injured or even killed if the front passenger
front air bag inflates in a collision which
could occur under some circumstances,
even with the air bag technology installed
in your vehicle. The only means to
completely eliminate this risk is to never
place a child in a rear-facing child restraint
in the front seat. We therefore strongly
recommend that you always place a child
in a rear-facing child restraint in a backseat.
R If you must install a rear-facing child
restraint on the front passenger seat
because circumstances require you to do
so, make sure the 001A001Cindicator
lamp is illuminated, indicating that the front
passenger front air bag is deactivated.
Should the 001A001Cindicator lamp not
illuminate or go out while the restraint is
installed, please chec kinstallation.
Periodically check the 001A001Cindicator
lamp while driving to make sure the 001A
001C indicator lamp is illuminated. If the
001A001Cindicator lamp goes out or
remains out, do not transport a child on the
front passenger seat until the system has
been repaired.
Ac hild in a rear-facing child restraint on the
front passenger seat will be seriously
injured or even killed if the front passenger
front air bag inflates.
R If you have to place a child in a forward-
facing child restraint on the front passenger
seat, move the seat as far back as possible,
use the proper child restraint
recommended for the age, size and weight
of the child, and secure child restraint with
the vehicle's seat belt according to the
child seat manufacturer's instructions. G
WARNING
If the child restraint system is installed
incorrectly on a suitable seat, it cannot
protect as intended. The child cannot then be
restrained in the event of an accident, heavy braking or sudden changes of direction. There
is an increased risk of injury, possibly even
fatal.
Make sure that you observe the child restraint
system manufacturer's installation
instructions and the notes on use. Please
ensure, that the base of the child restraint
system is always resting completely on the
seat cushion. Never place objects, e.g.
cushions, under or behind the child restraint
system. Only use child restraint systems with
the original cover designed for them. Only
replace damaged covers with genuine covers.
G
WARNING
If the child restraint system is installed
incorrectly 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,
striking vehicle occupants. There is an
increased risk of injury, possibly even fatal.
Always install child restraint systems
properly, even if they are not being used.
Make sure that you observe the child restraint
system manufacturer's installation
instructions. G
WARNING
Child restraint systems or their securing
systems which have been damaged or
subjected to a load in an accident can no
longer protect as intended. The child cannot
then be restrained in the event of an accident,
heavy braking or sudden changes of direction.
There is an increased risk of injury, possibly
even fatal.
Replace child restraint systems which have
been damaged or subjected to a load in an
accident as soon as possible. Have the
securing systems on the child restraint
system checked at a qualified specialist
workshop, before you install a child restraint
system again. Children in the vehicle
61Safety Z