center MERCEDES-BENZ M-Class 2015 W166 Owner's Guide

If OCS determines that:
R the front-passenger seat is unoccupied, the
PASSENGER AIR BAG OFF indicator lamp
lights up after the system self-test and
remains lit. This indicates that the front-
passenger front air bag is deactivated.
R the front-passenger seat is occupied by a
child of up to 12 months old, in a standard
child restraint system, the PASSENGER AIR BAG OFF indicator lamp lights up after the
system self-test and remains lit. This indi-
cates that the front-passenger front air bag
is deactivated.
But in the case of a 12-month-old child, in a standard child restraint system, the
PASSENGER AIR BAG OFF indicator lamp
can go out after the system self-test. This
indicates that the front-passenger front air
bag is activated. The result of the classifi-
cation is dependent on, among other fac-
tors, the child restraint system and the
child's stature. It is recommended that you
install the restraint system on a suitable
rear seat.
R the front-passenger seat is occupied by a
person of smaller stature (e.g. a teenager
or small adult), the PASSENGER AIR BAG
OFF indicator lamp lights up and remains lit after the system self-test depending on the result of the classification or, alternatively,
goes out.
- if the PASSENGER AIR BAG OFF indicator
lamp is off, move the front-passenger
seat as far back as possible. Alterna-
tively, a person of small stature can sit on
a rear seat.
- if the PASSENGER AIR BAG OFF indicator
lamp is lit, a person of smaller stature
should not use the front-passenger seat.
R the front-passenger seat is occupied by an
adult or a person of a stature correspond-
ing to that of an adult, the PASSENGER AIR BAG OFF indicator lamp goes out after the
system self-test. This indicates that the
front-passenger front air bag is activated. If children are traveling in the vehicle, be sure
to observe the notes on "Children in the vehi-
cle" (Y page 61).
When OCS is malfunctioning, the red 0075
restraint system warning lamp in the instru-
ment cluster and the PASSENGER AIR BAG
OFF indicator lamp light up simultaneously.
The front-passenger front air bag is deactiva-
ted in this case and does not deploy during an accident. Have the system checked by quali-
fied technicians as soon as possible. Consult
an authorized Mercedes-Benz Center. The
front-passenger seat should only be repaired at an authorized Mercedes-Benz Center.
If the front-passenger seat, the seat cover orthe seat cushion is damaged, have the nec-
essary repair work carried out at an author-
ized Mercedes-Benz Center.
For safety reasons, Mercedes-Benz recom-
mends that you only use seat accessories
that have been approved by Mercedes-Benz.
If the driver's air bag deploys, this does not
mean that the front-passenger front air bag
will also deploy. The Occupant Classification
System (OCS) categorizes the occupant in the
front-passenger seat. Depending on that
result, the front-passenger front air bag is
either enabled or deactivated.
System self-test G
DANGER
If the PASSENGER AIR BAG OFF indicator
lamp does not light up during the system self- test, then the system is malfunctioning. The
front-passenger front air bag might be trig-
gered unintentionally or might not be trig-
gered at all in the event of an accident with
high deceleration. This poses an increased
risk of injury or even fatal injury.
In this case the front-passenger seat may not be used. Do not install a child restraint system
on the front-passenger seat. Have the Occu-
pant Classification System (OCS) checked
and repaired immediately at a qualified spe-
cialist workshop. Occupant safety
55Safety Z

Problems with the Occupant Classification System (OCS)
Be sure to observe the notes on "System self-test" (Y
page 55).Problem
Possible causes/consequences and
0050
0050Solutions The PASSENGER AIR
BAG OFF indicator
lamp lights up and
remains lit, even
though the front-
passenger seat is occu-
pied by an adult or a
person of a stature cor-
responding to that of an
adult. The classification of the person on the front-passenger seat is
incorrect.
X Make sure the conditions for a correct classification of the per-
son on the front-passenger seat are met (Y page 53).
X If the PASSENGER AIR BAG OFF indicator lamp remains lit, the
front-passenger seat may not be used.
X Have OCS checked as soon as possible at an authorized
Mercedes-Benz Center. The PASSENGER AIR
BAG OFF indicator
lamp does not light up
and/or does not stay
on.
The front-passenger
seat is:
R unoccupied
R occupied by the
weight of a child up
to 12 months old in a
child restraint sys-
tem OCS is malfunctioning.
X Make sure there is nothing between the seat cushion and the
child seat.
X Make sure that the entire base of the child restraint system rests
on the seat cushion of the front-passenger seat. The backrest of
the forwards-facing child restraint system must, as far as pos-
sible, be resting on the backrest of front-passenger seat. If nec- essary, 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 and the child restraint system being pulled too tightly.
X Check the installation of the child restraint system.
Make sure that the head restraint does not apply a load to the
child restraint system. If necessary, adjust the head restraint
accordingly.
X Make sure that no objects are applying additional weight onto
the seat.
X If the PASSENGER AIR BAG OFF indicator lamp remains off, do
not install a child restraint system on the front-passenger seat. It is recommended that you install the restraint system on a
suitable rear seat.
X Have OCS checked as soon as possible at an authorized
Mercedes-Benz Center. Occupant safety
57Safety Z

portion of the seat belt. The seat belt cannot
be immediately refastened. There is an
increased risk of injury, possibly even fatal.
Stop the vehicle immediately, paying atten-
tion to road and traffic conditions. Reactivate the special seat belt retractor and secure the
child restraint system properly.
All seat belts in the vehicle, except the driv-
er's seat belt, are equipped with a special seat belt retractor. When activated, the special
seat belt retractor ensures that the seat belt
cannot slacken once the child seat is secured.
Installing a child restraint system:
X Make sure you observe the child restraint
system manufacturer's installation instruc-
tions.
X Pull the seat belt smoothly from the belt
outlet.
X Engage seat belt tongue in belt buckle.
Activating the special seat belt retractor:
X Pull the seat belt out fully and let the inertia
reel retract it again.
While the seat belt is retracting, you should hear a ratcheting sound. The special seat
belt retractor is enabled.
X Push the child restraint system down so
that the seat belt is tight and does not
loosen.
Removing a child restraint system/deactivat-
ing the special seat belt retractor:
X Make sure you observe the child restraint
system manufacturer's installation instruc- tions.
X Press the belt buckle release button, hold
the belt tongue and guide it back towards
the belt outlet.
The special seat belt retractor is deactiva-
ted. Child restraint system
The use of seat belts and child restraint sys-
tems is required by law in:
R all 50 states
R the U.S. territories
R the District of Columbia
R all Canadian provinces
If you install a rearward-facing child restraint
system on the center rear seat, the rear arm
rest must be folded back as far as possible.
You can obtain further information about the correct child restraint system from any
authorized Mercedes-Benz Center. G
WARNING
If the child restraint system is installed incor- rectly 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 instruc-
tions and the notes on use. Please ensure,
that the base of the child restraint system is
always resting completely on the seat cush-
ion. 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 incor- rectly 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, strik- ing vehicle occupants. There is an increased
risk of injury, possibly even fatal.
Always install child restraint systems prop-
erly, even if they are not being used. Make
sure that you observe the child restraint sys-
tem manufacturer's installation instructions. 62
Children in the vehicleSafety

Braking
X
Keep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. BAS PLUS (Brake Assist System
PLUS)
General information i
Observe the "Important safety notes" sec-
tion (Y page 67).
BAS PLUS is only available in vehicles equip-
ped with DISTRONIC PLUS.
For BAS PLUS to assist you, the radar sensor system must be operational.
With the help of the radar sensor system, BAS
PLUS can detect obstacles that are in the
path of your vehicle for an extended period of time.
If the radar sensor system is malfunctioning,
BAS PLUS will not be available. The brake
system is still available with complete brake
boosting effect and BAS.
BAS PLUS can help you to minimize the risk of
a collision with a vehicle or reduce the effects
of such a collision. If BAS PLUS detects a
danger of collision, you are assisted when
braking.
Important safety notes G
WARNING
BAS PLUS cannot always clearly identify
objects and complex traffic situations.
In such cases, BAS PLUS may:
R intervene unnecessarily
R not intervene
There is a risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake. Terminate the
intervention in a non-critical driving situation. G
WARNING
BAS PLUS does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
As a result, BAS PLUS may not intervene in all
critical situations. There is a risk of an acci-
dent.
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 there is interference by other radar sources
R there are 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 To avoid a collision, BAS PLUS calculates the
brake force necessary if:
R you approach an obstacle, and
R BAS PLUS has detected a risk of collision
When driving at a speed under 20 mph
(30 km/h): if you depress the brake pedal,
BAS PLUS is activated. The increase in brake pressure will be carried out at the last possi-
ble moment. Driving safety systems
69Safety Z

and the
00BAdistance warning lamp will light
up in the instrument cluster.
X Brake immediately in order to increase the
distance from the vehicle in front.
or
X Take evasive action, provided it is safe to do
so.
Due to the nature of the system, particularly
complicated but non-critical driving condi-
tions may also cause the system to display a
warning.
With the help of the radar sensor system, the
distance warning function can detect obsta-
cles that are in the path of your vehicle for an
extended period of time.
Up to a speed of about 40 mph (70 km/h), the distance warning function can also react to
stationary obstacles, such as stopped or
parked vehicles.
If you approach an obstacle and the distance
warning function detects a risk of a collision, the system will initially alert you both visually
and acoustically.
In particular, the detection of obstacles can
be impaired if:
R dirt on the sensors or anything else cover-
ing the sensors
R there is snow or heavy rain
R there is interference by other radar sources
R there are 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
R new vehicles or after the COLLISION PRE-
VENTION ASSIST system has been serv-
iced
Observe the notes in the section on break-
ing-in (Y page 156).
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensor 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.
Adaptive Brake Assist i
Observe the "Important safety notes" sec-
tion (Y page 67). G
WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist may:
R intervene unnecessarily
R not intervene
There is a risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake. Terminate the
intervention in a non-critical driving situation. G
WARNING
Adaptive Brake Assist does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R to stationary obstacles
R when cornering
As a result, Adaptive Brake Assist may not
intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake.
Due to the nature of the system, particularly
complicated but non-critical driving condi-
tions may also cause Brake Assist to inter-
vene.
Adaptive Brake Assist aids you in braking dur-
ing hazardous situations at speeds above
4 mph (7 km/h) and uses the radar sensor
system to evaluate the traffic situation.
With the help of Adaptive Brake Assist, the
distance warning signal can detect obstacles
that are in the path of your vehicle for an
extended period of time. Driving safety systems
71Safety Z

Should you approach an obstacle and Adap-
tive Brake Assist has detected a risk of colli-
sion, Adaptive Brake Assist calculates the
braking force necessary to avoid a rear-end
collision. Should you apply the brakes vigo-
rously, Adaptive Brake Assist will automati-
cally increase the braking force to a level suit- able for the traffic conditions.
X Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if:
R you release the brake pedal.
R there is no longer any danger of a collision.
R no obstacle is detected in front of your
vehicle.
Adaptive Brake Assist is then deactivated.
Vehicles with PRE-SAFE ®
:if adaptive Brake
Assist requires particularly high brake pres-
sure, preventive passenger protection meas-
ures (PRE-SAFE ®
) are deployed simultane-
ously.
Up to vehicle speeds of around 155 mph
(250 km/h), adaptive Brake Assist is capable
of reacting to moving objects that have
already been recognized as such at least once
over the period of observation. Adaptive
Brake Assist does not react to stationary
obstacles.
If Adaptive Brake Assist is not available due to
a malfunction in the radar sensor system, the brake system remains available with full
brake boosting effect and BAS.
In particular, the detection of obstacles can
be impaired if there is:
R dirt on the sensors or anything else cover-
ing the sensors
R there is snow or heavy rain
R there is interference by other radar sources
R there are 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
R new vehicles or after the COLLISION PRE-
VENTION ASSIST system has been serv-
iced
Observe the notes in the section on break- ing-in (Y page 156).
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensor 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. ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes" sec-
tion (Y page 67).
ESP ®
monitors driving stability and traction,
i.e. power transmission between the tires and
the road surface.
If ESP ®
detects that the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilize the
vehicle. The engine output is also modified to keep the vehicle on the desired course within
physical limits. ESP ®
assists the driver when
pulling away on wet or slippery roads. ESP ®
can also stabilize the vehicle during braking.
ETS/4ETS (Electronic Traction System) ETS/4ETS traction control is part of ESP
®
.
Traction control brakes the drive wheels indi- vidually if they spin. This enables you to pull
away and accelerate on slippery surfaces, for
example if the road surface is slippery on one
side. In addition, more drive torque is trans-
ferred to the wheel or wheels with traction.
Traction control remains active, even if you
deactivate ESP ®
.
In appropriate driving situations, activate the
off-road program (Y page 251).72
Driving safety systemsSafety

It may be best to deactivate ESP
®
in the fol-
lowing situations:
R when using snow chains
R in deep snow
R on sand or gravel
i Activate ESP ®
as soon as the situations
described above no longer apply. ESP ®
will
otherwise not be able to stabilize the vehi-
cle if the vehicle starts to skid or a wheel
starts to spin.
! Avoid spinning the driven wheels for an
extended period with ESP ®
deactivated.
You could otherwise damage the drivetrain.
Deactivating/activating ESP ®X
To switch off: press button0043.
The 00BB ESP®
OFF warning lamp in the
instrument cluster lights up.
X To switch on: press button0043.
The 00BB ESP®
OFF warning lamp in the
instrument cluster goes out.
Characteristics when ESP ®
is deactivated
If ESP ®
is deactivated and one or more wheels
start to spin, the 00E5ESP®
warning lamp in
the instrument cluster flashes. In such situa-
tions, ESP ®
will not stabilize the vehicle.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R engine torque is no longer limited and the
drive wheels are able to spin. The spinning of the wheels results in a cut-
ting action for better traction on loose sur- faces.
R traction control is still activated.
R ESP ®
still provides support when you
brake.
Off-road ESP ®
(vehicles with Off-Road
Engineering package) An ESP
®
system specifically suited to off-road
terrain is activated automatically once the off-
road program is activated (Y page 251).
Off-road ESP ®
intervenes with a delay if there
is oversteering or understeering, thus improv-
ing traction.
ESP ®
trailer stabilization General information
ESP
®
trailer stabilization is not available in
AMG vehicles.
If your vehicle/trailer combination begins to
swerve, ESP ®
assists you in this situation.
ESP ®
slows the vehicle down by braking and
limiting the engine output until the vehicle/
trailer combination has stabilized.
Important safety notes G
WARNING
If road and weather conditions are poor,
trailer stabilization will not be able to prevent the vehicle/trailer combination from swerv-
ing. Trailers with a high center of gravity can
tip over before ESP ®
can detect this. There is
a risk of an accident.
Always adapt your driving style to the prevail- ing road and weather conditions.
If your vehicle with trailer (vehicle/trailer
combination) begins to lurch, you can only
stabilize the vehicle/trailer combination by
depressing the brake firmly.
Trailer stabilisation is active above speeds of
about 37 mph (60 km/h). 74
Driving safety systemsSafety

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

STEER CONTROL
General information STEER CONTROL helps you by transmitting a
noticeable steering force to the steering
wheel in the direction required for vehicle
stabilization.
This steering assistance is provided in partic-
ular if:
R both right wheels or both left wheels are on
a wet or slippery road surface when you
brake.
R the vehicle starts to skid.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 67).
No steering support is provided from STEER
CONTROL, if:
R ESP ®
is malfunctioning.
R the lighting is faulty.
Power steering will, however, continue to
function. Theft deterrent locking system
Immobilizer
X To activate with the SmartKey: remove
the SmartKey from the ignition lock.
X To activate with KEYLESS-GO: switch the
ignition off and open the driver's door.
X To deactivate: switch on the ignition.
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Any-
one can start the engine if a valid SmartKey
has been left inside the vehicle.
i The immobilizer is always deactivated
when you start the engine.
In the event that the engine cannot be star- ted when the starter battery is fully charged, the immobilizer may be faulty.
Contact an authorized Mercedes-Benz
Center or call 1-800-FOR-MERCedes (in the
USA) or 1-800-387-0100 (in Canada). ATA (anti-theft alarm system)
X
To arm: lock the vehicle with the SmartKey
or KEYLESS-GO.
Indicator lamp 0043flashes. The alarm sys-
tem is armed after approximately
15 seconds.
X To deactivate using the SmartKey:
unlock the vehicle with the SmartKey.
or X Insert the SmartKey into the ignition lock.
X To deactivate using KEYLESS-GO: unlock
the vehicle with KEYLESS-GO.
or X Press the Start/Stop button on the dash-
board. The SmartKey must be inside the
vehicle.
A visual and audible alarm is triggered if the
alarm system is armed and you open:
R a door
R the vehicle with the mechanical key
R the tailgate
R the hood Theft deterrent locking system
77Safety Z

X
To turn the alarm off with the SmartKey:
press the 0036or0037 button on the
SmartKey.
The alarm is switched off.
or
X Insert the SmartKey into the ignition lock.
The alarm is switched off.
X To stop the alarm using KEYLESS-GO:
grasp the outside door handle. The Smart-
Key must be outside the vehicle.
The alarm is switched off.
or
X Press the Start/Stop button on the dash-
board. The SmartKey must be inside the
vehicle.
The alarm is switched off.
The alarm is not switched off, even if you
close the open door that triggered it, for
example.
i If the alarm continues for more than
30 second s,the mbrace emergency call
system automatically notifies the Cus-
tomer Assistance Center. This is done
either by text message or data connection.
The emergency call system sends the mes- sage or data provided that:
R you have subscribed to the mbrace ser-
vice.
R the mbrace service has been activated
properly.
R the necessary mobile phone network is
available. 78
Theft deterrent locking systemSafety