2017 MERCEDES-BENZ CLS child lock

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.
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.
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.Pets in the vehicle 63
Safety Z

BAS (Brake Assist System)
General information BAS operates in emergency braking situations.
If you depress the brake pedal quickly, BAS
automatically boosts the braking force, thus
shortening the stopping distance.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 64).
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.
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 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 64).
BAS PLUS is only available on vehicles with the
Driving Assistance 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 65).
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 corneringDriving safety systems 65
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. SmartKey functions
C
7 To lock the vehicleD
T To unlock the trunk lid

battery check lamp ( Y
page 79) flashes
twice.
Mechanical key
General notes If the vehicle can no longer be locked or
unlocked with the SmartKey, use the mechani-
cal key.
If you use the mechanical key to unlock and
open the driver's door or the trunk lid, the anti-
theft alarm system will be triggered. Switch off
the alarm ( Y
page 75).
If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked auto-
matically. X
To unlock the fuel filler flap: insert the
SmartKey into the ignition lock.
Removing the mechanical key
X
Push release catch C in the direction of the
arrow and at the same time remove mechan-
ical key D from the SmartKey.
For further information about: R
unlocking the driver's door ( Y
page 83)R
unlocking the trunk ( Y
page 86)R
locking the vehicle ( Y
page 83)
Inserting the mechanical key X
Push mechanical key D completely into the
SmartKey until it engages and release
catch C is back in its basic position. 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.78
SmartKey
Opening and closing

Problem
Possible causes/consequences and P Solutions
The engine cannot be
started using the Smart-
Key. The on-board voltage is too low. X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work: X
Check the starter battery and charge it if necessary ( Y
page 284).
or X
Jump-start the vehicle ( Y
page 285).
or X
Consult a qualified specialist workshop.
The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. The vehicle is locked. X
Unlock the vehicle and try to start the vehicle again.
There is interference from a powerful source of radio waves. X
Start your vehicle with the SmartKey in the ignition lock.
You have lost a Smart-
Key. X
Have the SmartKey deactivated at a qualified specialist workshop. X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well.
You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well.
Doors
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.
Unlocking and opening doors from
the inside You can open a door from inside the vehicle
even if it has been locked.
If the vehicle has previously been locked from
the outside, opening a door from the inside will
trigger the anti-theft alarm system. Switch off
the alarm ( Y
page 75).
You can only open the rear doors from inside the
vehicle if they are not secured by the child-proof
locks ( Y
page 63). Doors 81
Opening and closing Z

X
To unlock and open a front door: pull door
handle D .
If the door is locked, locking knob C pops up.
The door is unlocked and opens. X
To unlock a rear door: pull up locking knob
on the rear door.
The rear door is unlocked and can be opened. X
To open a rear door: pull the rear door han-
dle.
Centrally locking and unlocking the
vehicle from the inside You can centrally lock or unlock the vehicle from
the inside. The switches are on the driver’s door.
X
To unlock: press button C .X
To lock: press button D .
If all the doors are closed, the vehicle locks.
Meanwhile, the fuel filler flap will not be locked
or unlocked.
If the vehicle has been locked from the outside,
it cannot be centrally unlocked from the inside.
You can open a door from inside the vehicle
even if it has been locked. You can only open the rear doors from inside the
vehicle if they are not secured by the child-proof
locks ( Y
page 63).
If a locked door is opened from the inside, the
previous unlock status of the vehicle will be
taken into consideration if: R
the vehicle was locked using the locking but-
ton for the central locking, or R
if the vehicle was locked automatically
The vehicle will be fully unlocked if it had previ-
ously been fully unlocked. If only the driver's
door had been previously unlocked, only the
door which has been opened from the inside is
unlocked.
Automatic locking feature
X
To deactivate: press and hold button C for
about five seconds until a tone sounds. X
To activate: press and hold button D for
about five seconds until a tone sounds.
If you press one of the two buttons and do not
hear a tone, the relevant setting has already
been selected.
The vehicle is locked automatically when the
ignition is switched on and the wheels are turn-
ing.
You could therefore lock yourself out if: R
the vehicle is being pushed. R
the vehicle is being towed. R
the vehicle is on a roller dynamometer.
You can also switch the automatic locking func-
tion on and off using the on-board computer
( Y
page 199).82
Doors
Opening and closing

G WARNING
The reversing feature does not respond: R
to soft, light and thin objects, e.g. fingers R
over the last 1/3 in (8 mm) of the closing
movement
The reversing feature cannot prevent some-
one being trapped in these situations in par-
ticular. There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure.
If somebody becomes trapped: R
press the T button on the SmartKey, orR
pull or press the remote operating switch
on the driver's door or R
press the closing or locking button on the
trunk lid, or R
pull on the trunk lid handle
Opening/closing from outside
Opening
X
Press the 6 button on the SmartKey.X
Pull handle C .X
Raise the trunk lid. Closing X
Pull the trunk lid down using recess C .X
If necessary, lock the vehicle with the 7
button on the SmartKey ( Y
page 76) or with
KEYLESS-GO ( Y
page 76).
If KEYLESS-GO detects only one SmartKey in the
trunk after it closed, the trunk lid opens again. If
KEYLESS-GO detects a second SmartKey out-
side the vehicle, the trunk lid remains closed.
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 handle84
Trunk
Opening and closing

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.
Always switch off the engine before opening
the trunk lid. Never drive with the trunk lid
open.
! The trunk lid swings upwards when opened.
Therefore, make sure that there is sufficient
clearance above the trunk lid.
The opening dimensions of the trunk lid can be
found in the "Vehicle data" section
( Y
page 328).
Opening You can open the trunk lid automatically using
the SmartKey or the handle in the trunk lid. X
Press and hold the T button on the Smart-
Key until the trunk lid opens.
or X
If the trunk is unlocked, pull the trunk lid han-
dle and release it again immediately
( Y
page 84).
Closing
X
Press closing button C in the trunk lid.
Vehicles with trunk lid remote closing fea-
ture: you can simultaneously close the trunk lid
and lock the vehicle. The KEYLESS-GO key must
be in the rear detection range of the vehicle. X
Press locking button D in the trunk lid.
If all the doors are closed, the vehicle locks. If KEYLESS-GO detects only one SmartKey in the
trunk after it closed, the trunk lid opens again. If
KEYLESS-GO detects a second SmartKey out-
side the vehicle, the trunk lid remains closed.
Opening/closing automatically from
inside
Important safety notes
G WARNING
Parts of the body could become trapped dur-
ing automatic closing of the trunk lid. In addi-
tion, people may be standing in the closing
area or may enter the closing area, e.g. chil-
dren, during the closing procedure. There is a
risk of injury.
Make sure that nobody is in the vicinity of the
closing area during the closing process.
Release the remote operating switch imme-
diately if somebody becomes trapped. To re-
open the trunk lid, pull on the remote operat-
ing switch.
G WARNING
The trunk lid can be automatically opened or
closed even if the SmartKey is not in the vehi-
cle. If children are left unsupervised in the
vehicle, they could activate the functions.
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.
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.
Always switch off the engine before opening
the trunk lid. Never drive with the trunk lid
open. Trunk 85
Opening and closing Z