seat belt warning light MERCEDES-BENZ M-Class 2015 W166 Owner's Manual

BAS PLUS (Brake Assist System
PLUS)
.................................................... 69
Battery (SmartKey) Checking .......................................... 83
Important safety notes .................... 83
Replacing ......................................... 83
Battery (vehicle)
Charging ........................................ 389
Display message ............................ 301
Important safety notes .................. 387
Jump starting ................................. 391
Overview ........................................ 387
Belt
see Seat belts
Blind Spot Assist
Activating/deactivating ................. 276
Display message ............................ 308
Notes/function .............................. 237
Trailer towing ................................. 239
see Active Blind Spot Assist
BlueTEC
Adding DEF .................................... 180
BlueTEC (DEF) .................................... 451
Brake Assist see BAS (Brake Assist System)
Brake fluid
Display message ............................ 291
Notes ............................................. 453
Brake lamps
Changing bulb s.............................. 132
Display message ............................ 298
Brakes
ABS .................................................. 68
Adaptive Brake Assist ...................... 71
BAS .................................................. 68
BAS PLUS ........................................ 69
Brake fluid (notes) ......................... 453
Display message ............................ 285
High-performance brake system .... 189
Important safety notes .................. 188
Maintenance .................................. 189
Parking brake ................................ 184
Riding tips ...................................... 188
Warning lamp ................................. 320
Breakdown
see Flat tire
see Towing away Brightness control (instrument
cluster lighting)
................................... 35
Bulbs see Replacing bulbs C
California Important notice for retail cus-
tomers and lessees .......................... 26
Calling up a malfunction
see Display messages
Car
see Vehicle
Care
360° camera ................................. 376
Carpets .......................................... 379
Car wash ........................................ 372
Displa y........................................... 377
Exhaust pipe .................................. 376
Exterior lights ................................ 375
Gear or selector lever .................... 378
Interior ........................................... 377
Matte finish ................................... 374
Night View Assist Plus ................... 377
Notes ............................................. 371
Paint .............................................. 373
Plastic trim .................................... 378
Power washe r................................ 373
Rear view camera .......................... 376
Roof lining ...................................... 379
Seat belt ........................................ 379
Seat cover ..................................... 378
Sensors ......................................... 375
Steering wheel ............................... 378
Trim pieces .................................... 378
Washing by hand ........................... 373
Wheels ........................................... 374
Windows ........................................ 375
Wiper blades .................................. 375
Wooden trim .................................. 378
Cargo compartment cover
Notes/how to use ......................... 340
Cargo compartment enlargement
Important safety notes .................. 337
Cargo compartment floor
Opening/closing ............................ 344
Stowage well (under )..................... 344 6
Index

The shoulder section of the seat belt must
always be routed across the center of the
shoulder. Adjust the belt sash guide if neces-
sary.
X To raise: slide the belt guide upwards.
The belt guide will engage in various posi-
tions.
X To lower: hold belt guide release 0043and
slide the belt guide downwards.
X Let go of belt guide release 0043in the
desired position and make sure that the
belt guide engages.
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 61).
Releasing seat belts !
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. Dam-
aged seat belts can no longer fulfill their
protective function and must be replaced.
Visit a qualified specialist workshop. X
Press release button 0043, hold belt
tongue 0044and guide it back towards belt
outlet 0087.
Seat belt adjustment The seat-belt adjustment is an integral part of
the PRE-SAFE ®
convenience function. This
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 the belt tongue is engaged in the buckle
and
R the ignition is switched on
The seat-belt adjustment will apply a certain
tightening force if any slack is detected
between the vehicle 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 280).
Belt warning for the driver and front
passenger The
0076 seat belt warning lamp in the instru-
ment cluster is a reminder that all occupants
must fasten their seat belts. It may light up
continuously or flash. In addition, there may
be a warning tone.
Regardless of whether the driver's and front- passenger seat belts have already been fas-
tened, the 0076seat belt warning lamp lights
up for six seconds each time the engine is
started. If, after six seconds, the driver or
front-passenger seat belt has not been fas-
tened and the doors are closed, the 0076seat
belt warning lamp lights up. As soon as the
driver's and front-passenger seat belts are
fastened or a front door is opened again, the
0076 seat belt warning lamp goes out.
If the driver's seat belt is not fastened after
the engine is started, an additional warning
tone will sound. This warning tone stops after Occupant safety
49Safety Z

ton once or twice on vehicles with KEY-
LESS-GO.
The system carries out a self-diagnosis.
The PASSENGER AIR BAG OFF indicator lamp
must light up for approximately six second s.
The PA SSENGER AIR BAG OFF indicator lamp
then displays the status of the front-
passenger front air bag. If the status of the
front-passenger front air bag changes while
the vehicle is in motion, an air bag display
message may appear in the instrument clus-
ter (Y page 295). When the front-passenger
seat is occupied, always pay attention to the
PASSENGER AIR BAG OFF indicator lamp. Be aware of the status of the front-passenger
front air bag both before and during the jour-ney.
If the PASSENGER AIR BAG OFF indicator
lamp:
R is lit, the front-passenger front air bag is
deactivated. They will then not be deployed in the event of an accident.
R does not light up: the front-passenger
front air bag is enabled. If, in the event of an
accident, all deployment criteria are met,
the front-passenger front air bag is
deployed. G
WARNING
If the PASSENGER AIR BAG OFF indicator
lamp is lit, the front-passenger front air bag is disabled. It will not be deployed in the event of
an accident and cannot perform its intended
protective function. A person in the front-
passenger seat could then, for example, come
into contact with the vehicle's interior, espe-
cially if the person is sitting too close to the
dashboard. This poses an increased risk of
injury or even fatal injury.
When the front-passenger seat is occupied,
always ensure that:
R the classification of the person in the front-
passenger seat is correct and the front-
passenger front air bag is enabled or disa- bled in accordance with the person in the
front-passenger seat
R the front-passenger seat has been moved
back as far back as possible.
R the person is seated correctly.
Make sure, both before and during the jour-
ney, that the status of the front-passenger
front air bag is correct. G
WARNING
If you secure a child in a child restraint system on the front-passenger seat and the
PASSENGER AIR BAG OFF indicator lamp is
off, the front-passenger front air bag can
deploy in the event of an accident. The child
could be struck by the air bag. This poses an
increased risk of injury or even fatal injury.
Make sure that the front-passenger front air
bag has been disabled. The PASSENGER AIR
BAG OFF indicator lamp must be lit. G
WARNING
If you secure a child in a forward-facing child
restraint system on the front-passenger seat
and you position the front-passenger seat too close to the dashboard, the child could, in the
event of an accident:
R come into contact with the vehicle's inte-
rior if the PASSENGER AIR BAG OFF indi-
cator lamp is lit, for example
R be struck by the air bag if the PASSENGER
AIR BAG OFF indicator lamp is off
This poses an increased risk of injury or even
fatal injury.
Move the front-passenger seat as far back as possible. Always make sure that the shoulder
belt strap is correctly routed from the vehicle
belt sash guide to the shoulder belt guide on
the child restraint system. The shoulder belt
strap must be routed forwards and down-
wards from the vehicle belt sash guide. If nec- essary, adjust the vehicle belt sash guide and
the front-passenger seat accordingly. Always
observe the child restraint system manufac-
turer's installation instructions. 54
Occupant safetySafety

Deployment of Emergency Tensioning
Devices and air bags
Important safety notes G
WARNING
The air bag parts are hot after an air bag has
been deployed. There is a risk of injury.
Do not touch the air bag parts. Have a
deployed air bag replaced at a qualified spe-
cialist workshop as soon as possible. G
WARNING
A deployed air bag no longer offers any pro-
tection and cannot provide the intended pro-
tection in an accident. There is an increased
risk of injury.
Have the vehicle towed to a qualified special- ist workshop in order to have a deployed air
bag replaced.
It is important for your safety and that of any passengers 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. G
WARNING
Pyrotechnic Emergency Tensioning Devices
that have been deployed are no longer opera- tional and are unable to perform their inten-
ded protective function. This poses an
increased risk of injury or even fatal injury.
Therefore, have pyrotechnic Emergency Ten-
sioning Devices which have been triggered
immediately replaced at a qualified specialist workshop.
An electric motor is used by PRE-SAFE ®
to
trigger the tightening of the seat belt in haz-
ardous situations. This procedure is reversi-
ble.
If the Emergency Tensioning Devices or air
bags are deployed, you will hear a bang and a small amount of powder may also be released. The
0075restraint system warning
lamp will light up.
Only in rare cases will the bang affect your
hearing. The powder released is generally not hazardous to health, it could however cause
short-term breathing difficulties in people
with asthma or other respiratory problems. In
order to prevent breathing difficulties, you
should leave the vehicle as soon as it is safe to
do so, or open the window.
Air bags and pyrotechnic seat belt tensioners
contain perchlorate material, which may
require special handling or environmental
protection measures. Check with your local
government’s disposal guidelines. California
residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm.
Method of operation During the first stage of a collision, the
restraint system control unit evaluates impor-
tant physical data relating to vehicle deceler- ation or acceleration, such as:
R Duration
R Direction
R Intensity
Based on the evaluation of this data, the
restraint system control unit triggers the belt
tensioners in the event of a frontal or rear
collision.
An Emergency Tensioning Device can only be triggered if:
R the ignition is switched on
R the restraint system components are ready
for operation, see “Restraint system warn-
ing lamp” (Y page 45)
R the belt tongue is inserted into the buckle
on the respective front seat
The belt tensioners in the rear compartment
are triggered independently of the lock status
of the seat belts. 58
Occupant safetySafety

How the air bag system works is deter-
mined by the severity of the accident detec- ted, especially the vehicle deceleration or
acceleration, and the apparent type of acci- dent:
R frontal collision
R side impact
R rollover PRE-SAFE
®
(anticipatory occupant
protection system)
Introduction In certain hazardous situations, PRE-SAFE
®
takes pre-emptive measures to protect the
vehicle occupants.
Important safety notes !
Make sure that there are no objects in the
footwell or behind the seats. There is a dan- ger that the seats and/or objects could be
damaged when PRE-SAFE ®
is activated.
Although your vehicle is equipped with PRE-
SAFE ®
, the possibility of injury in the event of
an accident cannot be ruled out. Always
adapt your driving style to suit the prevailing
road and weather conditions and maintain a
safe distance from the vehicle in front. Drive
carefully.
Function PRE-SAFE
®
intervenes:
R in emergency braking situations, e.g. when
BAS is activated
R in critical driving situations, e.g. when phys-
ical limits are exceeded and the vehicle
understeers or oversteers severely
R on vehicles with the Active Driving Assis-
tance package: if BAS PLUS intervenes
powerfully or the radar sensor system
detects an imminent danger of collision in
certain situations PRE-SAFE
®
takes the following measures
depending on the hazardous situation detec-
ted:
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. The panorama roof with power tilt/sliding panel is completely
closed.
R vehicles with the memory function: the
front-passenger seat is adjusted if it is in an
unfavorable position.
R vehicles with a multicontour seat: the air
pressure in the side bolsters of the seat
backrest is increased.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pre-tensioning. On vehicles with mul-
ticontour seats, the air pressure in the side
bolsters is reduced again. All settings made
by PRE-SAFE ®
can then be reversed.
If the seat belt pre-tensioning is not reduced:
X Move the seat backrest or seat back
slightly when the vehicle is stationary.
The seat belt pre-tensioning is reduced and
the locking mechanism is released.
The seat-belt adjustment is an integral part of
the PRE-SAFE ®
convenience function. Infor-
mation about the convenience function can
be found under "Belt adjustment"
(Y page 49). Automatic measures after an acci-
dent
Immediately after an accident, the following
measures are implemented, depending on
the type and severity of the impact:
R by activating the hazard warning lamps
R the emergency lighting is activated
R the vehicle doors are unlocked
R the front side windows are lowered 60
Occupant safetySafety

R
in vehicles with a memory function: the
electrically adjustable steering wheel is
raised
R the engine is switched off
R vehicles with mbrace: automatic emer-
gency call Children in the vehicle
Important safety notes
Accident statistics show that children
secured in the rear seats are safer than chil-
dren secured in the front-passenger seat. For this reason, Mercedes-Benz strongly advises
that you install a child restraint system on a
rear seat. Children are generally better pro-
tected there.
If a child younger than 12 years and under 5 ft
(1.50 m) in height is traveling in the vehicle:
R always secure the child in a child restraint
system suitable for Mercedes-Benz vehi-
cles. The child restraint system must be
appropriate to the age, weight and size of
the child
R be sure to observe the instructions and
safety notes in this section in addition to
the child restraint system manufacturer's
installation instructions
R be sure to observe the instructions and
safety notes on the "Occupant classifica-
tion system (OCS)" (Y page 53)G
WARNING
If you leave children unsupervised in the vehi- cle, they could set it in motion by, for example:
R release the parking brake.
R shift the automatic transmission out of the
parking position P.
R start the engine.
In addition, they may operate vehicle equip-
ment and become trapped. There is a risk of
an accident and injury. When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle. G
WARNING
If persons, particularly children are subjected to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle. G
WARNING
If the child restraint system is subjected to
direct sunlight, parts may get very hot. Chil-
dren may burn themselves on these parts,
particularly on the metal parts of the child
restraint system. There is a risk of injury.
If you leave the vehicle, taking the child with
you, always ensure that the child restraint
system is not exposed to direct sunlight. Pro- tect it with a blanket, for example. If the child
restraint system has been exposed to direct
sunlight, let it cool down before securing the
child in it. Never leave children unattended in the vehicle.
Always ensure that all vehicle occupants have
their seat belts fastened correctly and are sit- ting properly. Particular attention must be
paid to children.
Observe the safety notes on the seat belt
(Y page 46) and the notes on correct use of
seat belts (Y page 47).
A booster seat may be necessary to achieve
proper seat belt positioning for children over
41 lbs (18 kg) or until they reach a height
where a lap/shoulder belt fits properly with-
out a booster seat. Special seat belt retractor
G
WARNING
If the seat belt is released while driving, the
child restraint system will no longer be
secured properly. The special seat belt retrac- tor is disabled and the inertia real draws in a Children in the vehicle
61Safety
Z

G
WARNING
PRE-SAFE ®
Brake does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
As a result, PRE-SAFE ®
Brake may neither
give warnings nor intervene in all critical sit-
uations. There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
In the event of snowfall or heavy rain, the rec-
ognition can be impaired.
Recognition by the radar sensor system is
also impaired in the event of:
R dirt on the sensors or anything else cover-
ing the sensors
R interference by other radar sources
R strong radar reflections, for example in
parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensors checked at a qualified spe-
cialist workshop. This also applies to colli-
sions at low speeds where there is no visible
damage to the front of the vehicle.
Function X
To activate/deactivate: activate or deac-
tivate PRE-SAFE ®
Brake in the on-board
computer (Y page 276).
If the PRE-SAFE ®
Brake is not activated, the
00D4 symbol appears in the multifunction
display.
Starting at a speed of around 4 mph (7 km/h),
this function warns you if you rapidly
approach a vehicle in front. An intermittent
warning tone will then sound and the 00BAdistance warning lamp will light up in the
instrument cluster.
X Brake immediately to defuse the situation.
or
X Take evasive action provided it is safe to do
so.
PRE-SAFE ®
Brake can also brake the vehicle
automatically under the following conditions:
R the driver and front-passenger have their
seat belts fastened
and
R the vehicle speed is between approx-
imately 4 mph (7 km/h) and 124 mph
(200 km/h)
At speeds of up to approximately 40 mph
(70 km/h) PRE-SAFE ®
Brake can also detect
stationary objects. Examples of stationary
objects are stopped or parked vehicles.
i If there is an increased risk of collision,
preventive passenger protection measures
(PRE-SAFE ®
) are activated.
If the risk of collision with the vehicle in front
remains and you do not brake, take evasive
action or accelerate significantly, the vehicle
may perform automatic emergency braking,
up to the point of full brake application. Auto- matic emergency braking is not performed
until immediately prior to an imminent acci-
dent.
You can prevent the intervention of the PRE-
SAFE ®
Brake at any time by:
R depressing the accelerator pedal further.
R activating kickdown.
R releasing the brake pedal.
The braking action of PRE-SAFE ®
Brake is
ended automatically if:
R you maneuver to avoid the obstacle.
R there is no longer any danger of a collision.
R there is no longer an obstacle detected in
front of your vehicle.
If you have activated DSR (Y page 250), PRE-
SAFE ®
Brake is deactivated. 76
Driving safety systemsSafety

Useful information
i This Operator's Manual describes all
models and all standard and optional equip- ment 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 special-
ist workshops (Y page 29). Correct driver's seat position
G
WARNING
You could lose control of your vehicle if you do the following while driving:
R adjust the driver's seat, head restraint,
steering wheel or mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt before starting the engine. X
Observe the safety guidelines on seat
adjustment (Y page 105).
X Make sure that seat 0087is adjusted prop-
erly.
Electrical seat adjustment (Y page 106)
When adjusting the seat, make sure that:
R you are as far away from the driver's air bag
as possible.
R you are sitting in a normal upright position.
R you can fasten the seat belt properly.
R you have moved the backrest to an almost
vertical position.
R you have set the seat cushion angle so that
your thighs are gently supported.
R you can depress the pedals properly.
X Check whether the head restraint is adjus-
ted properly.
When doing so, make sure that you have
adjusted the head restraint so that the back of your head is supported at eye level by the
center of the head restraint. Also make
sure that you have adjusted the head
restraint so that the back of your head is as close to the head restraint as possible. Thiswill be the case if the head restraint is
adjusted correctly (Y page 107).
X Observe the safety guidelines on steering
wheel adjustment (Y page 111).
X Make sure that steering wheel 0043is adjus-
ted properly.
Adjusting the steering wheel manually
(Y page 111)
Adjusting the steering wheel electrically
(Y page 112)
When adjusting the steering wheel, make
sure that:
R you can hold the steering wheel with your
arms slightly bent.
R you can move your legs freely.
R you can see all the displays in the instru-
ment cluster clearly.
X Observe the safety guidelines for seat belts
(Y page 46). 104
Correct driver's seat positionSeats, steering wheel and mirrors

Problems with the seat ventilation
Problem
Possible causes/consequences and
0050
0050Solutions The seat ventilation has
switched off prema-
turely or cannot be
switched on. The on-board voltage is too low because too many electrical con-
sumers are switched on.
X Switch off electrical consumers that you do not need, such as
the rear window defroster or interior lighting.
Once the battery is sufficiently charged, the seat ventilation will
switch back on automatically. Steering wheel
Important safety notes
G
WARNING
You could lose control of your vehicle if you do the following while driving:
R adjust the driver's seat, head restraint,
steering wheel or mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt before starting the engine. G
WARNING
Children could injure themselves if they
adjust the steering wheel. There is a risk of
injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never leave children unsupervised in the vehicle. Adjusting the steering wheel man-
ually
G
WARNING
If the steering wheel is unlocked while the
vehicle is in motion, it could change position
unexpectedly. This could cause you to lose
control of the vehicle. There is a risk of an
accident. Before starting off, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion.
0043
Release lever
0044 To adjust the steering wheel height
0087 To adjust the steering wheel position
(fore-and-aft adjustment)
X Push release lever 0043down completely.
The steering column is unlocked.
X Adjust the steering wheel to the desired
position.
X Push release lever 0043up completely.
The steering column is locked.
X Check if the steering column is locked.
When doing so, try to push the steering
wheel up or down or try to move it in the
fore-and-aft direction. Steering wheel
111Seats, steering wheel and mirrors Z

In addition, at least one of the following con-
ditions must be fulfilled:
R the engine is switched off.
R the driver's door is open and the seat belt is
not fastened.
R the vehicle is stationary for a lengthy
period.
The red 0049(USA only) or 0024(Canada
only) indicator lamp in the instrument cluster
lights up.
i The electric parking brake is not automat-
ically engaged if the engine is switched off
by the ECO start/stop function.
Releasing automatically The electric parking brake is released auto-
matically when all of the following conditions
are fulfilled:
R the engine is running.
R the transmission is in position Dor R.
R the seat belt has been fastened.
R you depress the accelerator pedal.
If the transmission is in position R, the trunk
lid must be closed.
If your seat belt is not fastened, the following conditions must be fulfilled to automatically
release the electric parking brake:
R the driver's door is closed.
R you have shifted out of transmission posi-
tion Por you have previously driven faster
than 2 mph (3 km/h).
i Ensure that you do not depress the accel-
erator pedal unintentionally. Otherwise the
parking brake will be released and the vehi-
cle will start to move. Emergency braking X
While driving, push handle 0043of the electric
parking brake.
The vehicle can also be braked during an
emergency by using the electric parking
brake.
i The vehicle is braked for as long as the
handle of the electric parking brake is
pressed. The longer the electric parking
brake handle is depressed, the greater the
braking force.
During braking:
R a warning tone sounds
R the Release Park. Brake Release Park. Brake message
appears
R the red 0049(USA only) or 0024(Canada
only) indicator lamp in the instrument clus- ter flashes
When the vehicle has been braked to a stand-
still, the electric parking brake is engaged. Parking the vehicle for a long period
If you leave the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharging.
X Connecting a trickle charger.
i You can obtain information about trickle
chargers from a qualified specialist work-
shop.
If you leave the vehicle parked for longer than
six weeks, the vehicle may suffer damage as a result of lack of use. Parking
185Driving and parking Z