MERCEDES-BENZ M-Class 2014 W166 Service Manual

Overhea
dcontrol panel Function Page
0002
0015
Switches the left-
hand reading lamp on/off 127
0003
0006
Switches the front
interio rlighting on 128
0023
0002
Switches the rear
interior lighting on/off 128
0022
001D
Switches the front
interior lighting/automatic
interior lighting control off 128
0020
0015
Switches the right-
hand reading lamp on/off 127
0021
0002
Opens/closes the
sliding sunroof 98
0003
Opens/closes the
panorama roof with power
tilt/sliding panel with roller
sunblinds 99 Function Page
0014
Eyeglasses compartment 334
0015
0009
Roadside Assistance
call button (mbrace
system) 353
0016
000A
SOS button (mbrace
system) 351
0017
000B
MB Info call button
(mbrace system) 353
0018
Rear-view mirror 114
001A
Buttons for the garage door
opener
361
001B
Microphone for mbrace
(emergency call system)
telephone and the Voice
Control System 1 1
Voice Control System only available together with COMAND. Observe the additional operating instructions. Overhead control panel
39At a glance

Door control panel
Function Page
0002
Opens the door 87
0003
000C000B
Unlocks/locks
the vehicle 87
0023
00100014000D
Stores settings fo
rthe seat,
exterior mirrors and
steering wheel (memory
function) 117
0022
Adjusts the seats 105
0020
0005000800110009
Adjusts and folds the
exterior mirrors in/out
electrically
114 Function Page
0021
0005
Opens/closes the
side windows 94
0014
000F
Opens/closes the
tailgate 92
0015
000E
Activates/
deactivates the override
feature for the side
windows in the rear
compartment 6640
Doorc
ontrol panelAt a glance

Useful information
..............................42
Panic alarm .......................................... 42
Occupant safety .................................. 42
Children in the vehicle ........................60
Driving safet ysystems ....................... 66
Theft deterrent locking system .........76 41Safety

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

SRS (Supplemental Restraint System)
Introduction SRS consists of:
R
001F SRS warning lamp
R air bags
R the air bag control unit with crash sensors
R ETDs for the front seat belts and the outer
seat belts in the rear
R seat belt force limiters
SRS reduces the risk of vehicle occupants
coming into contact with parts of the
vehicle's interior in the event of an accident.
It can also reduce the forces to which vehicle
occupants are subjected during an accident.
SRS warning lamp G
WARNING
If SRS is malfunctioning, child restraint
system components may be triggered
unintentionally or might not be triggered at all
in the event of an accident with a high rate of
vehicle deceleration. There is an increased
risk of injury, possibly even fatal.
Have SRS checked and repaired immediately
at a qualified specialist workshop.
SRS functions are checked regularly when
you switch on the ignition and when the
engine is running. Therefore, malfunctions
can be detected in good time.
The 001F SRS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out no later than a few seconds
after the engine is started.
The SRS components are in operational
readiness when the 001FSRS warning lamp
goes out while the engine is running. There is a malfunction if:
R
the 001F SRS warning lamp does not light
up when the ignition is switched on
R the engine is running and the 001FSRS
warning lamp does not go out after a few
seconds
R the engine is running and the 001FSRS
warning lamp lights up again
Safety guidelines for seat belts,
Emergency Tensioning Devices (ETDs)
and air bags G
WARNING
R Damaged seat belts or seat belts that have
been subjected to stress in an accident
must be replaced. Their anchoring points
must also be checked. Only use seat belts
installed or supplied by an authorized
Mercedes-Benz Center.
R Air bags and pyrotechnic Emergency
Tensioning Devices (ETDs) contain
perchlorate material, which may require
special handling and regard for the
environment. Check your national disposal
guidelines. California residents, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm .
R Air bags and ETDs are designed to function
on a one-time-only basis. An air bag or ETD
that has deployed must be replaced. PRE-
SAFE ®
has electrically operated reversible
belt tensioners in addition to the
pyrotechnic ETDs.
R Do not pass seat belts over sharp edges.
They could tear.
R Do not make any modification that could
change the effectiveness of the seat belts.
R 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.
R No modifications of any kind may be made
to any components or wiring of the SRS.
R Do not change or remove any component
or part of the SRS. Occupant safety
43Safety
Z

R
Do not install additional trim material, seat
covers, badges, etc. to the:
-padded steering wheel boss
- knee bag covers
- front-passenge rair bag cover
- outer side of front seat bolsters
- outer side of rear bench seat backrest
seat bolsters
- roof lining trim
R Do not install additional electrical/
electronic equipment on or near SRS
components and wiring.
R Keep area betwee nair bags and occupants
free of objects (e.g. packages, purses,
umbrellas, etc.).
R Do not hang items such as coat hangers
from the coat hooks or handles over the
door. These items may be thrown around in
the vehicle and cause head and other
injuries when the window curtain air bag is
deployed.
R Air bag system components will be hot after
an air bag has inflated. Do not touch them.
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 Improper repair work on the SRS creates a
risk of rendering the SRS inoperative or
causing unintended air bag deployment.
Work on the SRS must therefore only be
performed by qualified technicians.
Contact an authorized Mercedes-Benz
Center.
R For your protection and the protection of
others, when scrapping the air bag unit or
ETD, our safety instructions must be
followed. These instructions are available
fro ma ny authorized Mercedes-Benz
Center.
R Given the considerable deployment speed,
required inflation volume, and the material
of the ai rbags, there is the possibility of
abrasions or other, potentially more serious
injuries resulting from air bag deployment. If you sell your vehicle
,Mercedes-Benz
strongly recommends that you inform the
subsequent owner that the vehicle is
equipped with SRS. Also, refer them to the
applicable section in the Operator's Manual. Air bags
Important safety notes G
WARNING
Using unsuitable seat cover scould restric tor
even preven tdeployment of the air bags
integrated into the seats. Consequently, the
air bags cannot protec tvehicle occupants as
they are designed to do. In addition, the
function of the air bag deactivation system
could be restricted. This poses an increased
risk of injury or even fatal injury.
You should only use seat covers that have
been approved for the respective seat by
Mercedes-Benz. G
WARNING
The air bag parts are hot after the airbag has
been deployed. There is a risk of injury.
Do not touch the air bag parts. Have the
deployed air bags replaced at a qualified
specialist workshop as soon as possible. G
WARNING
Air bags are designed to reduce the incidence
of injuries and fatalities in certain situations:
R frontal impacts (driver's and front-
passenger fron tair bags and driver's knee
bag)
R side impacts (side impact air bags and
window curtain air bags)
R rollover (window curtain air bags)
However, no system available today can
completely eliminate injuries and fatalities.
When the air bags are deployed, a small
amount of powder is released .The powder
generally does not constitute a health hazard
and does not indicate that there is a fire in the 44
Occupant safetySafety

vehicle. In order to prevent potential
breathing difficulties, you should leave the
vehicle as soon as it is safe to do so. If you
have any breathing difficulty but cannot get
out of the vehicle after the air bag inflates,
then get fresh air by opening a window or
door. G
WARNING
In order to reduce the potential dange rof
injuries caused during the deploymen tofthe
front air bags, the driver and front passenger
must always be correctly seated and wear
their seat belts.
For maximum protection in the event of a
collision, you must always be in the normal
seat position with your back against the
backrest. Fasten your seat belt and make sure
that it is correctly positioned on your body.
As the air bag inflates with considerable
speed and force, a proper seating position
and correct positioning of the hands on the
steering wheel will help to keep you at a safe
distance from the air bag. Occupants who are
not wearing their seat belt, are not seated
properly or are too close to the air bag can be
seriously injured or killed by an air bag, as it
inflates with great force instantaneously:
R sit with the seat belt fastened correctly and
in a position that is as upright as possible
with your back against the backrest.
R move the driver's seat as far back as
possible, still permitting proper operation
of vehicle controls. The distance from the
center of the driver's chest to the center of
the air bag cover on the steering wheel
must be at least 10 inches (25 cm). You
should be able to accomplish this by
adjusting the seat and steering wheel. If
you have any difficulties, please contact an
authorized Mercedes-Ben zCenter.
R do not lean your head or chest close to the
steering wheel or dashboard.
R only hold the steering wheel on the outside.
Placing hands and arms inside the rim can
increase the risk and potential severity of hand/arm injury if the driver front air bag
inflates.
R adjust the front-passenger seat as far back
as possible from the dashboard when the
seat is occupied.
R occupants, especially children, should
never place their bodies or lean their heads
in the area of the door where the side
impact air bag inflates .This could result in
serious or fatal injuries should the side
impact air bag be deployed. 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.
Failure to follow these instructions can result
in severe injuries to you or other occupants.
If you sell your vehicle, it is important that you
make the buyer aware of this safety
information. Be sure to give the buyer this
Operator's Manual.
If the air bags 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.
The air bag installation locations are
identified by the AIR BAG symbol.
The air bags are deployed if the air bag control
unit detects the need for deployment.O nly in
the event of such a situatio nwill the air bags
provide their supplemental protection.
If the drive rand front passenge rdo not wear
their seat belts, it is not possible for the air Occupant safety
45Safety Z

bags to provide their supplemental
protection.
In the event of other types of impacts and
impacts below air bag deployment
thresholds, the air bags will not deploy. The
driver and passenger will then be protected
to the extent possible by a properly fastened
seat belt.
Aproperly fastened seat belti s also
needed to provide the best possible
protection in a rollover.
Air bags provide additional protection; they
are not, however, a substitute for seat belts.
All vehicle occupants must fasten their seat
belts regardless of whether your vehicle is
equipped with air bags or not.
It is important for your safety and that of your
passenger to have deployed air bags replaced
and to have any malfunctioning air bags
repaired. This will help to make sure the air
bags continue to perform their protective
function for the vehicle occupants in the
event of a crash.
i After an air bag has been deployed, have
the vehicle towed to the nearest qualified
specialist workshop, even if your vehicle is
ready to drive.
Front air bags Driver's air bag
0002deploys in front of the
steering wheel; front-passenger front air
bag 0003deploys in front of and above the glove
box.
The front air bags increase protection for the
driver's and front passenger's head and
chest. They are deployed:
R
at the start of an accident with a high rate
of vehicle acceleration or deceleration in a
longitudinal direction
R if the system determines that air bag
deployment can offer additional protection
to that provided by the seat belt
R depending on whether the seat belt is being
used
R independently of other air bags in the
vehicle
If the vehicle rolls over, the front air bags are
generally not deployed. If the system detects
high vehicle deceleration in alongitudinal
direction, the front air bags are deployed.
Your vehicle has adaptive, two-stage front air
bags. In the event of a collision, the air bag
control unit evaluates the vehicle
deceleration. In the first deployment stage,
the front air bag is filled with enough
propellant gas to reduce the risk of injuries.
The front air bag is fully deployed if a second
deployment threshold is exceeded within a
few milliseconds.
The deployment of front-passenger front air
bag 0003is also influenced by the weight
category of the front passenger, which is
determined by the Occupant Classification
System (OCS) (Y page 49).
The lighter the passenger-side occupant, the
higher the vehicle deceleration rate required
(predicted at the start of the impact) for
second-stage inflation of the front-passenger
front air bag. In the second stage, the front
air bags are inflated with the maximum
amount of propellant gas available.
The front air bags are not deployed in
situations where a low impact severity is
predicted. You will then be protected by the
fastened seat belt. 46
Occupant safetySafety

Front-passenger front air bag
0003will only
deploy if:
R the system, based on the OCS weight
senso rreadings, has detected that the
front-passenger seat is occupied.
R the PASSENGER AIRBAG OFF indicator
lamp on the center console is not lit.
(Y page 49)
R the air bag control unit predicts a high
impact severity.
Driver's knee bag Driver's knee bag
0002deploys under the
steering column. The driver's knee bag is
always deployed along with the driver's front
air bag. The driver's knee bag is designed to
operate together with the fron tair bags in
frontal impacts if certain thresholds are
exceeded. The driver's knee bag operates
best in conjunction with correctly positioned
and fastened seat belts.
The driver's knee bag increases protection of
the drive ragainst:
R knee injuries
R thigh injuries
R lower leg injuries
Side impact air bags G
WARNING
Using unsuitable seat covers could restric tor
even preven tdeployment of the air bags
integrated into the seats. Consequently, the
air bags cannot protec tvehicle occupants as they are designed to do. In addition, the
function of the air bag deactivation system
could be restricted. This poses an increased
risk of injury or even fatal injury.
You should only use seat covers that have
been approved for the respective seat by
Mercedes-Benz.
G
WARNING
Sensors to control the air bags are located in
the doors. Modifications or work not
performed correctly to the doors or door
paneling, as well as damaged doors, can lead
to the function of the sensors being impaired.
The air bags might therefore not function
properly any more. Consequently, the air bags
cannot protec tvehicle occupants as they are
designed to do. There is an increased risk of
injury.
Never modify the doors or parts of the doors.
Always have work on the doors or door
paneling carried out at a qualified specialist
workshop.
You should only use seat covers that have
been approved for your vehicle by Mercedes-
Benz .The seat covers must have a special
tear seam for side impact air bags. Otherwise,
the side impact air bags cannot deploy
correctly and therefore cannot provide the
intended protection in the event of an
accident. Front side impact air bags
0002and rear side
impact air bags 0003deploy next to the outer
seat cushions. Occupant safety
47Safety Z

When deployed, the side impact air bags offer
additional protection for the thorax and, on
the fron tseats, the pelvis of the vehicle
occupants on the side of the vehicle on which
the impact occurs. However, they do not
protect the:
R head
R neck
R arms
The side impact air bags are deployed:
R on the side on which an impact occurs
R at the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in aside impact
R regardless of whether the seat belt on the
driver's seat and the outer seats of the 2nd
row of seats is used
R independently of the front air bags
R independently of the ETDs
If the vehicle rolls over, the side impac tair
bags are generally not deployed. side impact
air bags are deployed if the system detects
high vehicle deceleration or acceleration in a
lateral direction, or also if the vehicle rolls
over, and the system determines that side
impac tair bag deploymen tcan offer
additional protection to that provided by the
seat belt.
Side impac tair bags will not deploy in side
impacts which do not exceed the system's
prese tdeployment thresholds for lateral
acceleration/deceleration .You will then be
protected by the fastened seat belt.
The side impact air bag on the front-
passenger side is not deployed in the
following situations:
R the OCS system detects that the front-
passenger seat is not occupied, and
R the front-passenger seat belt is not
fastened.
The side impact air bag on the front-
passenger side will deploy if the front-
passenger seat belt is fastened, regardless of whether the front-passenger seat is occupied
or not.
Window curtain air bags
Window curtain air bags
0002enhance the level
of protection for the head, but not chest or
arms, of the vehicle occupants on the side of
the vehicle on which the impact occurs.
The window curtain air bags are integrated
into the side of the roof frame and deploy in
the area from the A-pillar to the C-pillar.
Window curtain air bags are deployed:
R at the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in aside impact
R on the side on which an impac toccurs
R on the driver's side and passenger side, in
the event of a vehicle rollover and if the
system determines that ai rbag deployment
can offer the vehicle occupants additional
protection to that provided by the seat belt
R independently of the use of the seat belt
R regardless of whether the front-passenger
seat is occupied
R independently of the fron tair bags
Window curtain air bags 0002will not deploy in
the even tofimpacts which do not exceed the
system's preset deployment thresholds for
vehicle acceleration/deceleration. You will
then be protected by the fastened seat belt. 48
Occupant safetySafety