
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 a standard child
restraint or as being a small individual (such
as a young teenager or a small adult), the
42 indicator lamp will illuminate
for approximately 6 seconds when the engine
is started and then, depending on occupant
weight sensor readings from the front-
passenger seat, remain illuminated or go out.
With the 42 indicator lamp
illuminated, the front-passenger front air bag
is deactivated. With the 42
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 42 indicator lamp
will illuminate for approximately 6 seconds
when the engine is started and then go out,
indicating that the front-passenger front air
bag is activated.
If the 42 indicator lamp is
illuminated, the front-passenger front air bag
is deactivated and will not be deployed.
If the 42 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 impact exceeds a preset deployment
threshold
R independently of the side impact air bags
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 OCS
For further information, see the section
regarding air bag display messages
( Y page 386).GWarning
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 appropriately sized
child restraint system or booster seat
recommended for the size and weight of the
child.
The infant or child restraint system 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 appropriate 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 A child 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
Occupant safety49SafetyZ

fastened, the 7 seat belt warning lamp
lights up for six seconds each time the engine
is started. It then goes out once the driver and
the front passenger have fastened their seat
belts.
If the driver's seat belt is not fastened after
the engine is started, an additional warning
tone will sound. The warning tone goes out
after approximately six seconds or once the
driver's seat belt is fastened.
If, after six seconds, the driver or front-
passenger have not fastened their seat belts
and the doors are closed:
R the 7 seat belt warning lamp remains
illuminated as long as either the driver's or
front-passenger seat belt is not fastened.
R if the vehicle speed exceeds 15 mph
(25 km/h), the 7 seat belt warning
lamp lights up. Additionally, a warning tone
will sound with increasing intensity for a
maximum of 60 seconds or until the
driver's and front-passenger seat belt are
fastened.
If the driver/front passenger unfasten their
seat belt while the vehicle is in motion, the
7 seat belt warning lamp lights up and a
warning tone sounds again.
The warning tone ceases even if the driver or
front passenger have still not fastened their
seat belt after 60 seconds. The 7 seat belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated and the 7 seat
belt warning lamp flashes again if the vehicle
speed again exceeds 15 mph (25 km/h) .
The 7 seat belt warning lamp only goes
out if:
R both the driver and the front passenger
have fastened their seat belts.
or
R the vehicle is stationary and a door is open.
i For more information on the 7 seat
belt warning lamp, see "Indicator andwarning lamps in the instrument cluster,
seat belt" ( Y page 414).
Emergency Tensioning Devices and
seat belt force limiters
The front seat belts and the outer seat belts
in the rear are equipped with ETDs and belt
force limiters.
! If the front-passenger seat is not
occupied, do not engage the seat belt
tongue in the buckle on the front-
passenger seat. Otherwise, the Emergency
Tensioning Device could be triggered in the
event of an accident.
The belt tensioners tighten the seat belts in
an accident, pulling them close against the
body.
Belt tensioners do not correct incorrect seat
positions or incorrectly fastened seat belts.
Belt tensioners do not pull vehicle occupants
back towards the backrest.
Seat belt force limiters, when triggered, help
to reduce the peak force exerted by the seat
belt on the vehicle occupant.
The front belt force limiters are synchronized
with the front air bags, which take on a part
of the deceleration force. Thus, the force
exerted on the occupant is distributed over a
greater area.
The belt tensioners can only be activated
when:
R the ignition is switched on.
R the restraint systems are operational; see
"SRS warning lamp" ( Y page 42).
R the belt tongue is engaged in the buckle on
each of the three-point seat 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 belt tensioners on the outside seats in the
rear compartment are triggered
independently of the lock status of the seat
belts.
Occupant safety59SafetyZ

section must never be exploited in a reckless
or dangerous manner which could jeopardize
the user's safety or the safety of others.
Always adjust your driving style to the
prevailing road and weather conditions and
keep a safe distance to other road users and
objects on the street.
If a driving system malfunctions, other driving
safety systems may also switch off. Observe
indicator and warning lamps that may come
on as well as messages in the multifunction
display that may appear.GWarning!
HYBRID vehicles: It is imperative that you read
the HYBRID Supplemental Operating
Instructions included in your vehicle literature
portfolio. You may otherwise not receive all
necessary safety information and warning for
the operation of your vehicle.
i In wintry driving conditions, always use
winter tires (M+S tires) and if necessary,
snow chains. Only in this way will the
driving safety systems described in this
section work as effectively as possible.
ABS (Anti-lock Braking System)
Important safety notes
GWarning
Observe "Important safety notes"
( Y page 66).
GWarning
Do not pump the brake pedal. Use firm, steady
brake pedal pressure instead. Pumping the
brake pedal defeats the purpose of the ABS
and significantly reduces braking
effectiveness.
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the
vehicle when braking.
ABS works from a speed of about
5 mph (8 km/h) upwards, regardless of road-
surface conditions. ABS works on slippery
surfaces, even when you only brake gently.
The ! warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
Braking
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
XIf ABS intervenes: continue to depress the
brake pedal with force until the braking
situation is over.XTo make a full brake application:
depress the brake pedal with full force.GWarning
If the ABS malfunctions, other driving systems
such as the BAS or the ESP ®
are also switched
off. Observe indicator and warning lamps that
may come on as well as messages in the
multifunction display that may appear.
If the ABS malfunctions, the wheels may lock
during hard braking, reducing the steering
capability and extending the braking distance.
The pulsating brake pedal can be an
indication of hazardous road conditions and
functions as a reminder to take extra care
while driving.
BAS (Brake Assist System)
GWarning
Observe "Important safety notes"
( Y page 66).
BAS operates in emergency braking
situations. If you depress the brake pedal
quickly, BAS automatically boosts the braking
force, thus shortening the stopping distance.
XKeep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking.Driving safety systems67SafetyZ

Rdisturbance from other radar sources
R strong radar reflection such as in parking
garages
BAS PLUS uses radar signals that are not
reflected well by narrow objects and
absorptive materials. For this reason BAS
PLUS will not react to persons, animals, and
approaching traffic or cross-traffic.
BAS PLUS may not detect narrow vehicles
driving in front of you, such as motorcycles
and vehicles driving offset from your vehicle
center.
Following a collision or accident-related
damage to the front end of the vehicle, have
the configuration and operation of the radar
sensors checked at an authorized Mercedes-
Benz Center.
If BAS PLUS is not available due to a
malfunction in the radar sensor system, the
brake system remains available with full
brake boosting effect and BAS.
Adaptive brake lights
i Adaptive brake lamps are only available in
the USA and only on the S 600 and S65
AMG.
If you brake sharply from a speed of more
than 30 mph (50 km/h) or if braking is
assisted by BAS or BAS PLUS, the brake
lamps flash rapidly. In this way, traffic
traveling behind you is warned in an even
more noticeable manner.
If you brake from a speed of more than
40 mph (70 km/h) to a standstill, the hazard
warning lamps are switched on automatically
when the vehicle is stationary. If the brakes
are applied again, the brake lamps light up
continuously. The hazard warning lamps
switch off automatically if you drive faster
than 6 mph (10 km/h) again. You can also
switch off the hazard warning lamps using the
hazard warning lamp button ( Y page 276).
ESP ®
(Electronic Stability Program)
Important safety notesGWarning
Observe "Important safety notes"
( Y page 66).
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. If necessary, 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.
If ESP ®
intervenes, the ÷ warning lamp
flashes in the instrument cluster.
GWarning
Under no circumstances should you
deactivate ESP ®
when the ÷ ESP®
warning lamp in the instrument cluster
flashes. Proceed as follows:
R when driving off, apply as little throttle as
possible.
R while driving, ease up on the accelerator
pedal.
R adapt your speed to suit the prevailing road
and weather conditions.
failure to observe these guidelines could
cause the vehicle to skid. ESP ®
cannot
prevent accidents resulting from excessive
speed.
! Vehicles without 4MATIC: switch the
ignition off when:
R the electric parking brake is being tested
using a brake dynamometer.
R the vehicle is being towed with the front/
rear axle raised.
Application of the brakes by ESP ®
may
otherwise destroy the brake system.
Driving safety systems69SafetyZ

! Vehicles with 4MATIC: switch off the
ignition when the electric parking brake is
being tested on a brake dynamometer.
Application of the brakes by ESP ®
may
otherwise destroy the brake system.
i Only use wheels with the recommended
tire sizes. Only then will ESP ®
function
properly.
ETS/4ETS (Electronic Traction System)GWarning
Observe "Important safety notes"
( Y page 66).
Traction control is part of ESP ®
.
Traction control brakes the drive wheels
individually 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. On vehicles with 4MATIC, more
drive torque is also transferred to the wheel
or wheels with traction.
Traction control remains active if you
deactivate ESP ®
.
Activating/deactivating ESP ®
GWarning!
The ESP should not be switched off during
normal driving other than in the
circumstances described below. Disabling
the system will reduce vehicle stability in
driving maneuvers.
Do not switch off the ESP when a spare wheel
is mounted.
GWarning
S 63 AMG: ESP ®
should not be deactivated
during normal driving.
Deactivating the system results in the
following:
R no restriction to the engine torque
R loss of system-supported traction control
"ESP OFF" is designed for driving on closed
tracks when the vehicle's own oversteering
and understeering characteristics are desired
and requires an extremely qualified and
experienced driver who is able to handle
these critical driving situations.
You could lose control of your vehicle and
cause an accident.
Beware of these limits if you deactivate
ESP ®
.
Do not deactivate ESP ®
when the emergency
or spare wheel is mounted.
ESP ®
is activated automatically when the
engine is running.
It may be best to deactivate ESP ®
in the
following situations:
R when using snow chains
R in deep snow
R on sand or gravelGWarning!
Switch on the ESP immediately if the
aforementioned circumstances do not apply
anymore. Otherwise the ESP will not stabilize
the vehicle when it is starting to skid or a
wheel is spinning.
When you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R the engine's torque is no longer limited and
the drive wheels can spin. The spinning of
the wheels results in a cutting action, which
provides better grip.
R traction control is still activated.
R ESP ®
still provides support when you
brake.
If ESP ®
is deactivated and one or more wheels
start to spin, the ÷ warning lamp in the
instrument cluster flashes. In such situations,
ESP ®
will not stabilize the vehicle.
XTo deactivate: (Y page 375).
The å warning lamp in the instrument
cluster lights up.70Driving safety systemsSafety

In order to maintain an appropriate distance
from the vehicle in front and thus prevent a
collision, you must apply the brakes yourself.
At speeds up to approximately
40 mph (70 km/h), PRE-SAFE ®
Brake may
also detect stationary obstacles, for example
stopped or parked vehicles.GWarning!
If you do not receive visual or acoustic
warning signals, the PRE-SAFE ®
Brake may
R not have recognized the collision risk
R have been deactivated
R be malfunctioning
Apply the brakes yourself to avoid a collision.
XTo activate/deactivate: activate or
deactivate PRE-SAFE ®
Brake in the on-
board computer ( Y page 376).
After activation, the Ä symbol is
displayed on the left in the instrument
cluster.
For PRE-SAFE ®
Brake to assist you when
driving, the radar sensor system must be
switched on and operational.
PRE-SAFE ®
Brake does not always detect
complex traffic situations properly. You can
terminate the braking action of PRE-SAFE ®
Brake in a non-critical driving situation at any
time if:
R an acoustic and visual warning occurs.
R the vehicle brakes.
To stop the braking action, you can either
depress the accelerator pedal further,
activate kickdown or release the brake pedal.
The braking action of PRE-SAFE ®
Brake is
ended automatically if:
R you maneuver to avoid the obstacle.
R your speed drops below approximately
9 mph (15 km/h).
R there is no longer an obstacle detected in
front of your vehicle.
R there is no longer any danger of a collision.
Following a collision or collision-related
damage to the front end of the vehicle, have
the configuration and operation of the radar
sensors checked. Choose a qualified
specialist workshop which has the necessary
specialist knowledge and tools for the work
required. Mercedes-Benz recommends that
you use an authorized Mercedes-Benz Center
for this purpose.
Anti-theft systems
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct key.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
key that is left inside the vehicle.
XTo activate with the SmartKey: remove
the SmartKey from the ignition lock.XTo activate with KEYLESS-GO: switch the
ignition off and open the driver's door.XTo deactivate: switch on the ignition.
i
The immobilizer is always deactivated
when you start the engine.
ATA (Anti-Theft Alarm system)
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 trunk lid
R the hood
The alarm is not switched off, even if you
close the open door that has triggered it, for
example.
Anti-theft systems73SafetyZ

Important information about using
KEYLESS-GO
RYou can use the KEYLESS-GO key as a
conventional SmartKey.
RYou can combine KEYLESS-GO functions
with those of a conventional SmartKey, e.g.
you can open the vehicle with KEYLESS-GO
and close it with the & button.
RAlways carry your KEYLESS-GO key on your
person.
RNever store the KEYLESS-GO key together
with:
-electronic devices, such as a mobile
phone or other SmartKey
-metal objects, such as coins or metal foil
Doing so may impair the function of
KEYLESS-GO.
RTo open or close the vehicle, the KEYLESS-
GO key should not be more than 3 ft (1 m)
from the door or trunk.
RIf the vehicle is parked for more than
72 hours, the KEYLESS-GO function is
deactivated. Pull an outer door handle and
switch on the ignition to reactivate the
KEYLESS-GO function.
RIf the KEYLESS-GO key is removed from the
vehicle, the system may not be able to
recognize the SmartKey anymore. The
vehicle can then no longer be locked or
started with KEYLESS-GO.
RIf the KEYLESS-GO key has been removed
from the vehicle, e.g. when another vehicle
occupant with a KEYLESS-GO key leaves
the vehicle:
-when the Start/Stop button is pressed,
or when trying to lock the vehicle using
the locking button on the outside door
handle, the Key Not Detected message
appears in the multifunction display.
-when the engine is running, the red Key
Not Detected message appears in the
multifunction display as you pull away.
Look for the KEYLESS-GO key and place
it somewhere else in the vehicle. Place
the KEYLESS-GO key on the front-
passenger seat, for example, or in your
shirt pocket.
RIf you have switched on the engine with the
Start/Stop button, you can switch it off
again by:
-pressing the Start/Stop button
-inserting the KEYLESS-GO key into the
ignition lock while the vehicle is at a
standstill and the automatic
transmission is in park position P.
RYou may inadvertently unlock the vehicle if
the KEYLESS-GO key is less than 3 ft (1 m)
from the vehicle and:
-an exterior door handle is hit by a jet of
water, or
-you clean an exterior door handle
RPlease note that any vehicle occupant can
start the engine when there is a KEYLESS-
GO key in the vehicle.
Scenario 1: There is a KEYLESS-GO key in
the vehicle and a second one outside the
vehicle. If you leave the KEYLESS-GO key
in the vehicle when you leave and lock the
vehicle, no message appears in the
multifunction display.
Scenario 2: There is a KEYLESS-GO key in
the vehicle, but none outside the vehicle. If
you get out of the vehicle and attempt to
lock it, the Key Detected In Vehicle
message appears in the multifunction
display. The vehicle is not then locked.
When starting the engine and whilst driving,
KEYLESS-GO also checks whether a valid
SmartKey is in the vehicle by periodically
establishing radio contact.
78SmartKeyOpening and closing

ProblemPossible causes/consequences and M SolutionsThe engine cannot be
started using the
SmartKey.The on-board voltage is too low.XRemove the SmartKey and reinsert it into the ignition lock.XStart the engine within 30 seconds of inserting the SmartKey
into the ignition lock.XRepeat if necessary.
If the engine does not start after several attempts:
XCheck the starter battery and charge it if necessary
( Y page 468).
or
XJump-start the vehicle ( Y page 471).
or
XConsult a qualified specialist workshop.The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle.A door is open. Therefore, the SmartKey cannot be detected as
easily.XClose the door and try to start the vehicle again.There is interference from a powerful source of radio waves.XStart your vehicle with the SmartKey in the ignition lock.Doors
Important safety notes
GWarning!
When leaving the vehicle, always remove the
SmartKey from the starter switch. Always
take the SmartKey with you and lock the
vehicle. Do not leave children unattended in
the vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. The children
could
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
starter switch or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and the child could be burned by these
parts.GWarning
Do not carry heavy or hard objects in the
passenger compartment unless they are
firmly secured in place.
Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of:
R strong braking maneuvers
R sudden changes of direction
R an accident
82DoorsOpening and closing