2017 MERCEDES-BENZ S CLASS child lock

of the child restraint system must always rest on
the seat cushion of the front-passenger seat.
The backrest of the child restraint system must
lie as flat as possible against the backrest of the
front-passenger seat. The child restraint system
must not touch the roof or be subjected to a load
by the head restraint. Adjust the angle of the
seat backrest and the head restraint position
accordingly. Always make sure that the shoul-
der belt strap is correctly routed from the vehi-
cle belt outlet to the shoulder belt guide on the
child restraint system. The shoulder belt strap
must be routed forwards and downwards from
the vehicle belt outlet. If necessary, adjust the
vehicle belt outlet and the front-passenger seat
accordingly.
Always observe the child restraint system man-
ufacturer's installation and operating instruc-
tions.
Child-proof locks
Important safety notes
G WARNING
If children are traveling in the vehicle, they
could: R
open doors, thus endangering other people
or road users R
exit the vehicle and be caught by oncoming
traffic R
operate vehicle equipment and become
trapped
There is a risk of an accident and injury.
Always activate the child-proof locks and
override feature if children are traveling in the
vehicle. When leaving the vehicle, always take
the key with you and lock the vehicle. Never
leave children unattended in the vehicle.
Override feature for: R
the rear doors ( Y
page 65)R
the rear side windows ( Y
page 65) 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.64
Children in the vehicle
Safety

Child-proof locks for the rear doors
You secure each door individually with the child-
proof locks on the rear doors. A door secured
with a child-proof lock cannot be opened from
inside the vehicle. When the vehicle is unlocked,
the door can be opened from the outside. X
To activate: press the child-proof lock lever
up in the direction of arrow C .X
Make sure that the child-proof locks are work-
ing properly. X
To deactivate: press the child-proof lock
lever down in the direction of arrow D .
Override feature for the rear side win-
dows
X
To activate/deactivate: press button D .
If indicator lamp C is lit, operation of the rear
side windows is disabled. Operation is only
possible using the switches in the driver's
door. If indicator lamp C is off, operation is
possible using the switches in the rear com-
partment. When the override feature is activated, the con-
trols in the rear compartment are disabled for: R
the rear side windows R
adjustment of the front-passenger seat from
the rear compartment R
the sunblinds: -
of the rear side windows -
of the rear window -
in the roof
Pets in the vehicle
G WARNING
If you leave animals unattended or unsecured
in the vehicle, they could press buttons or
switches, for example.
As a result, they could: R
activate vehicle equipment and become
trapped, for example R
activate or deactivate systems, thereby
endangering other road users
Unsecured animals could also be flung around
the vehicle in the event of an accident or sud-
den steering or braking, thereby injuring vehi-
cle occupants. There is a risk of an accident
and injury.
Never leave animals unattended in the vehi-
cle. Always secure animals properly during
the journey, e.g. use a suitable animal trans-
port box.
Driving safety systems
Overview of driving safety systems In this section, you will find information about
the following driving safety systems: R
ABS ( A nti-lock B raking S ystem)
( Y
page 66) R
BAS ( B rake A ssist S ystem) ( Y
page 66)R
BAS PLUS ( B rake A ssist S ystem PLUS) with
Cross-Traffic Assist ( Y
page 67)R
COLLISION PREVENTION ASSIST PLUS
( Y
page 68)Driving safety systems 65
Safety Z

G WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
Brakes 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) with Cross-Traffic Assist
General information BAS PLUS can help you to minimize the risk of a
collision with a vehicle or a pedestrian and
reduce the effects of such a collision. If BAS
PLUS detects a danger of collision, you are
assisted when braking.
i Pay attention to the important safety notes
in the "Driving safety systems" section
( Y
page 66).
BAS PLUS is only available in vehicles with the
Driving Assistance Plus package.
For BAS PLUS to assist you when driving, the
radar sensor system and the camera system
must be operational.
With the help of a sensor system and a camera
system, BAS PLUS can detect obstacles: R
that are in the path of your vehicle for an
extended period of time R
that cross the path of your vehicle
In addition, pedestrians in the path of your vehi-
cle can be detected.
BAS PLUS detects pedestrians by using typical
characteristics such as the body contours and
posture of a person standing upright.
If the radar sensor system or the camera system
is malfunctioning, BAS PLUS functions are
restricted or no longer available. The brake sys-
tem is still available with complete brake boost-
ing effect and BAS. i Observe the restrictions described in the
"Important safety notes" section
( Y
page 67).
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 cannot always clearly identify peo-
ple, this is especially the case if they are mov-
ing. BAS PLUS cannot intervene in these
cases. There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
G WARNING
BAS PLUS does not react: R
to small people, e.g. children R
to animals R
to oncoming vehicles 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 if: R
there is dirt on the sensors or anything else
covering the sensors R
there is interference by other radar sources R
there are strong radar reflections, for exam-
ple in parking garagesDriving safety systems 67
Safety Z

SmartKey
Important safety notes
G WARNING
If children are left unsupervised in the vehicle,
they could: R
open the doors, thus endangering other
people or road users. R
get out and disrupt traffic. R
operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake. R
shifting the automatic transmission out of
park position PR
Start the engine.
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 or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
G WARNING
If you attach heavy or large objects to the
SmartKey, the SmartKey could be uninten-
tionally turned in the ignition lock. This could
cause the engine to be switched off. There is a
risk of an accident.
Do not attach any heavy or large objects to the
SmartKey. Remove any bulky key rings before
inserting the SmartKey into the ignition lock.
! Keep the SmartKey away from strong mag-
netic fields. Otherwise, the remote control
function could be affected.
Strong magnetic fields can occur in the vicin-
ity of powerful electrical installations.
Do not keep the SmartKey: R
with electronic devices, e.g. a mobile phone
or another SmartKey. R
with metallic objects, e.g. coins or metal foil. R
inside metallic objects, e.g. a metal case.
This can affect the functionality of the Smart-
Key. Do not keep the SmartKey in the temperature-
controlled cup holder ( Y
page 292). On vehicles
with the KEYLESS-GO start function, do not
keep it on the parcel shelf or in the trunk. Oth-
erwise, the SmartKey may not be detected, e.g.
when starting the engine using the Start/Stop
button.
A brief radio connection between the vehicle
and the SmartKey determines whether a valid
SmartKey is in, or in the direct vicinity of, the
vehicle. This occurs, for example: R
when starting the engine R
while driving R
when using HANDS-FREE ACCESS R
when the external door handles are touched R
during convenience closing
SmartKey functions
C
7 Locks the vehicleD
T Opens/closes the trunk lid

SmartKey battery
Important safety notes
G WARNING
Batteries contain toxic and corrosive substan-
ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatal
injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
H Environmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately
and recycled to protect the
environment.
Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified spe-
cialist workshop or a special
collection point for used bat-
teries.
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. National guide-
lines must be observed during disposal. In Cal-
ifornia, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/index.cfm .
Mercedes-Benz recommends that you have the
batteries replaced at a qualified specialist work-
shop. Checking the battery X
Press the 7 or 6 button.
The battery is working properly if battery
check lamp C lights up briefly.
The battery is discharged if battery check
lamp C does not light up briefly. X
Change the battery ( Y
page 80).
If the SmartKey battery is checked within the
signal reception range of the vehicle, pressing
the 7 or 6 button: R
locks or R
unlocks the vehicle
i You can obtain a battery from any qualified
specialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery. X
Take the mechanical key out of the SmartKey
( Y
page 79).
X
Press mechanical key D into the SmartKey
opening in the direction of the arrow until bat-
tery compartment cover C opens. Do not
hold battery compartment cover C closed
while doing so. X
Remove battery compartment cover C .80
SmartKey
Opening and closing

Door s
Important safet y notes
G WARNING
If children are lef t unsupervised in th e vehicle,
they could: R
ope n th e doors , thus endangerin g other
people or road users. R
get out and disrup t traffic .R
operat e th e vehicle' s equipment.
Additionally, children could set th e vehicle in
motion if, fo r example, they:R
release th e parking brake .R
shiftin g th e automatic transmissio n out of
par k position PR
Start th e engine.
There is a ris k of an acciden t and injury.
Whe n leavin g th e vehicle, always take th e
SmartKey wit h you and loc k th e vehicle. Never
leav e children or animals unattended in th e
vehicle. Always keep th e SmartKey out of
reach of children .
Unlockin g an d opening doors from
th e insideYou can ope n a doo r from insid e th e vehicle
eve n if it has bee n locked. You can only ope n th e
rea r doors from insid e th e vehicle if they are no t
secure d by th e child-proof locks ( Y
page 65). If
th e vehicle has bee n locke d wit h th e SmartKey
or wit h KEYLESS-GO , opening a doo r from th e
insid e will trigger th e anti-thef t alar m system.
Switc h of f th e alar m ( Y
page 76) . X
To unlock an d ope n a front door: pull doo r
handle D .
If th e doo r is locked, locking knob C pop s up.
The doo r is unlocke d and opens .X
To unlock a rear door: pull rea r doo r handle.
The locking knob on th e rea r doo r pop s up and
th e rea r doo r unlocks .X
To ope n a rear door: pull rea r doo r handle
again .
The rea r doo r opens .
Centrally locking an d unlocking th e
vehicle from th e insideYou can centrall y loc k and unloc k th e vehicle
from th e inside. The buttons are located on bot h
fron t doors .
X
To unlock : press butto n C .X
To lock : press butto n D .
If th e front-passenger doo r is closed, th e vehi-
cl e locks .
If th e driver's doo r is open, th e doo r stays
unlocked.
Meanwhile, th e fue l filler flap will no t be locke d
or unlocked.
You canno t unloc k th e vehicle centrall y from th e
insid e if th e vehicle has bee n locke d wit h th e
SmartKey or KEYLESS-GO .
The doors can be opene d from th e inside. You
can only ope n th e rea r doors from insid e th e
vehicle if they are no t secure d by th e child-proof
locks ( Y
page 65).
If th e vehicle has bee n locke d wit h th e SmartKey
or wit h KEYLESS-GO , opening a doo r from th e
insid e will trigger th e anti-thef t alar m system.
Switc h of f th e alar m ( Y
page 76) .Doors 83
Opening and closing Z

Vehicles with HANDS-FREE ACCESS:
It is also possible to stop the closing process by
performing a kicking movement under the rear
bumper.
Opening and closing manually
Opening X
Press the T button on the SmartKey.
or X
Pull handle C .
The trunk lid opens.
Closing
X
Pull the trunk lid down using recess C .
Vehicles with trunk lid remote closing fea-
ture or power closing: X
Lightly push the trunk lid closed.
The power closing function pulls the trunk lid
closed. X
Lock the vehicle if necessary with the 7
button on the SmartKey or with KEYLESS-GO
( Y
page 78).
If KEYLESS-GO detects a SmartKey in the
trunk, the trunk lid cannot be locked. It then
opens again.
Opening/closing automatically from
outside
Important safety notes
G WARNING
Parts of the body could become trapped dur-
ing automatic closing of the trunk lid. More-
over, people, e.g. children, may be standing in
the closing area or may enter the closing area
during the closing process. There is a risk of
injury.
Make sure that nobody is in the vicinity of the
closing area during the closing process.
Use one of the following options to stop the
closing process: R
press the T button on the SmartKey. R
pull or press the remote operating switch
on the driver's door. R
press the closing or locking button on the
trunk lid. R
pull the trunk lid handle
Vehicles with HANDS-FREE ACCESS:
It is also possible to stop the closing process by
performing a kicking movement under the rear
bumper.
G WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Exhaust
gases can enter the vehicle interior if the
trunk lid is open when the engine is running,
especially if the vehicle is in motion. There is a
risk of poisoning.86
Trunk
Opening and closing

When closing make sure that no parts of the
body are in the closing area. If somebody
becomes trapped, release the switch or press
the switch to open the side window again.
G WARNING
If children operate the side windows they
could become trapped, particularly if they are
left unsupervised. There is a risk of injury.
Activate the override feature for the rear side
windows. When leaving the vehicle, always
take the SmartKey with you and lock the vehi-
cle. Never leave children unsupervised in the
vehicle.
Side window reversing feature The side windows are equipped with an auto-
matic reversing feature. If a solid object blocks
or restricts a side window from traveling
upwards during the automatic closing process,
the side window opens again automatically. Dur-
ing the manual closing process, the side window
only opens again automatically after the corre-
sponding switch is released.
The automatic reversing feature is only an aid
and does not relieve you of the responsibility of
paying attention when closing a side window.
G WARNING
The reversing feature does not react: R
to soft, light and thin objects, e.g. small fin-
gers R
while resetting
This means that the reversing feature cannot
prevent someone being trapped in these sit-
uations. There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure. If
someone becomes trapped, press the switch
to open the side window again. Opening and closing the side win-
dows The switches for all side windows are located on
the driver's door. There is also a switch on each
door for the corresponding side window.
The switches on the driver's door take prece-
dence.
C
Front left D
Front right