engine MERCEDES-BENZ CLS 2018 Owner's Manual

i The immobilizer is always deactivated when
you start the engine.
In the event that the engine cannot be started
(yet the vehicle's battery is charged), the sys-
tem is not operational. 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 C flashes. The alarm system
is armed after approximately 15 seconds. X
To disarm: unlock the vehicle with the Smart-
Key or KEYLESS-GO.
or X
Insert the SmartKey into the ignition lock.
or X
Vehicles with KEYLESS-GO: press the
Start/Stop button.
The SmartKey must be in 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 trunk lid R
the hood X
To stop the alarm with the SmartKey:
press the 6 or 7 button on the Smart-
Key.
The alarm is stopped.
or X
Vehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock
( Y
page 124). X
Insert the SmartKey into the ignition lock.
The alarm is stopped. X
To stop the alarm using KEYLESS-GO:
grasp the outside door handle. The SmartKey
must be outside the vehicle.
The alarm is stopped.
or X
Press the Start/Stop button on the dash-
board. The SmartKey must be inside the vehi-
cle.
The alarm is stopped.
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 seconds, the mbrace emergency call sys-
tem automatically notifies the Customer
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 service. R
the mbrace service has been activated
properly. R
the necessary mobile phone network is
available.Protection against theft 75
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

tions of KEYLESS-GO with those of a conven-
tional SmartKey. Unlock the vehicle by using
KEYLESS-GO, for instance, and lock it using the
7 button on the SmartKey.
When locking or unlocking with KEYLESS-GO,
the distance between the SmartKey and the cor-
responding door handle must not be greater
than 3 ft (1 m).
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 the external door handles are touched R
when starting the engine R
while the vehicle is in motion
X
To unlock the vehicle: touch the inner sur-
face of the door handle. X
To lock the vehicle: touch sensor sur-
face C .X
Convenience closing feature: touch
recessed sensor surface D for an extended
period.
Further information on the convenience clos-
ing feature ( Y
page 88).X
To unlock the trunk lid: pull the handle on
the trunk lid.
The vehicle only unlocks the trunk lid.
Deactivating and activating If you do not intend to use a SmartKey for an
extended period of time, you can deactivate the
KEYLESS-GO function of the SmartKey. The
SmartKey will then use very little power, thereby
conserving battery power. For the purposes of
activation/deactivation, the vehicle must not be
nearby. X
To deactivate: press the 7 button on the
SmartKey twice in rapid succession.
The battery check lamp of the SmartKey
( Y
page 79) flashes twice briefly and lights
up once, then KEYLESS-GO is deactivated. X
To activate: press any button on the Smart-
Key.
or X
Insert the SmartKey into the ignition lock.
KEYLESS-GO and all of its associated features
are available again.
Changing the settings of the locking
system You can change the settings of the locking sys-
tem. This means that only the driver's door and
the fuel filler flap are unlocked when the vehicle
is unlocked. This is useful if you frequently travel
alone. X
To change the setting: press and hold down
the 6 and 7 buttons simultaneously
for approximately six seconds until the bat-
tery check lamp ( Y
page 79) flashes twice.
If the setting of the locking system is changed
within the signal range of the vehicle, pressing
the 7 or 6 button: R
locks or R
unlocks the vehicle
The SmartKey now functions as follows: X
To unlock: press the 6 button once.X
To unlock centrally: press the 6 button
twice. X
To lock centrally: press the 7 button.
The KEYLESS-GO function is changed as fol-
lows: X
To unlock the driver's door: touch the inner
surface of the door handle on the driver's
door. X
To unlock centrally: touch the inner surface
of the door handle on the front-passenger
door or the rear door. X
To lock centrally: touch the outer sensor
surface on one of the door handles. X
To restore the factory settings: press and
hold the 6 and 7 buttons simultane-
ou
sly fo r approximately six seconds until theSmartKey 77
Opening and closing Z

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

Locking/unlocking the driver's door
with the mechanical key
i If you want to centrally lock the vehicle using
the mechanical key, begin by pressing the
locking button for the interior locking mech-
anism while the driver's door is open. Then
lock the driver's door using the mechanical
key.
X
To unlock: turn the mechanical key counter-
clockwise as far as it will go to position G .X
To lock: turn the mechanical key clockwise as
far as it will go to position G .
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm sys-
tem will be triggered. Switch off the alarm
( Y
page 75).
Trunk
Important safety notes
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.
G WARNING
If objects, luggage or loads are not secured or
not secured sufficiently, they could slip, tip
over or be flung around and thereby hit vehicle occupants. There is a risk of injury, particu-
larly in the event of sudden braking or a sud-
den change in direction.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey.
! 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).
You should preferably place luggage or loads in
the trunk. Observe the loading guidelines
( Y
page 242).
Do not leave the SmartKey in the trunk. You
could otherwise lock yourself out.
Vehicles without the trunk lid remote clos-
ing feature: the trunk lid can be: R
opened and closed manually from outside R
opened automatically from outside R
opened automatically from inside R
locked separately R
opened with the emergency release button R
unlocked with the mechanical key
Vehicles with the trunk lid remote closing
feature: the trunk lid can be: R
opened and closed manually from outside R
opened/closed automatically from outside R
opened/closed automatically from inside R
locked separately R
opened with the emergency release button R
unlocked with the mechanical key
Trunk lid reversing feature The trunk lid is equipped with an automatic
reversing feature. It reacts if a solid object
obstructs or restricts the trunk lid during the
closing procedure. The trunk lid opens again
automatically. The automatic reversing feature
is only an aid and is not a substitute for your
attentiveness when closing the trunk. Trunk 83
Opening and closing Z

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

X
To open fully: press the switch beyond the
point of resistance and release it.
Automatic operation is started. X
To close manually: pull and hold the corre-
sponding switch. X
To close fully: pull the corresponding switch
beyond the pressure point.
Automatic operation is started. X
To interrupt automatic operation: press/
pull the corresponding switch again.
If you press/pull the switch beyond the point of
resistance, automatic operation is started in the
corresponding direction. You can stop auto-
matic operation by pressing/pulling the switch
again.
You can continue to operate the side windows
after you switch off the engine or remove the
SmartKey. This function is available for up to five
minutes or until the driver's or front-passenger
door is opened.
When the override feature for the side windows
is activated, the side windows cannot be oper-
ated from the rear ( Y
page 63).
Convenience opening
General notes You can ventilate the vehicle before you start
driving. To do this, the SmartKey is used to carry
out the following functions simultaneously: R
unlock the vehicle R
open the side windows R
open the sliding sunroof R
switch on the seat ventilation for the driver's
seat
The convenience opening feature can only be
operated using the SmartKey. The SmartKey
must be in close proximity to the vehicle.
The "convenience opening" feature is also avail-
able when the vehicle is unlocked.
Convenience opening X
Press and hold the 6 button until the side
windows and the sliding sunroof are in the
desired position. X
To interrupt convenience opening: release
the 6 button. Convenience closing feature
Important safety notes Information on the side window reversing fea-
ture ( Y
page 87).
G WARNING
When the convenience closing feature is oper-
ating, parts of the body could become trapped
in the closing area of the side window and the
sliding sunroof. There is a risk of injury.
Observe the complete closing procedure
when the convenience closing feature is oper-
ating. Make sure that no body parts are in
close proximity during the closing procedure.
Proceed as follows if someone is trapped:
With the SmartKey: X
Release the 7 button.X
Press the 6 button until the side windows
and the sliding sunroof reopen.
With KEYLESS-GO: X
Release the sensor surface on the door han-
dle. X
Immediately pull and hold the door handle
and keep the door handle pulled.
The side windows and the sliding sunroof
open.
General notes When you lock the vehicle, you can simultane-
ously: R
close the side windows R
close the sliding sunroof
Using the SmartKey X
Vehicles without KEYLESS-GO: point the tip
of the SmartKey at the door handle on the
driver's door. X
Vehicles with KEYLESS-GO: the SmartKey
must be in close proximity to the vehicle. X
Press and hold the 7 button until the side
windows and the sliding sunroof are fully
closed. X
Press and hold the 7 button until the side
windows are fully closed.88
Side windows
Opening and closing

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.
Observe the following when adjusting steering
wheel C , seat belt D and driver's seat

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
If you adjust the seat height carelessly, you or
other vehicle occupants could be trapped and
thereby injured. Children in particular could
accidentally press the electrical seat adjust-
ment buttons and become trapped. There is a
risk of injury.
While moving the seats, make sure that your
hands or other body parts do not get under the
lever assembly of the seat adjustment sys-
tem.
G WARNING
When you adjust a seat, you or other vehicle
occupants could become trapped, e.g. on the
seat guide rail. There is a risk of injury.
Make sure when adjusting a seat that no one
has any body parts in the sweep of the seat.
! To avoid damage to the seats and the seat
heating, observe the following information: R
keep liquids from spilling on the seats. If
liquid is spilled on the seats, dry them as
soon as possible. R
if the seat covers are damp or wet, do not
switch on the seat heating. The seat heat-
ing should also not be used to dry the seats. R
clean the seat covers as recommended;
see "Interior care". R
do not transport heavy loads on the seats.
Do not place sharp objects on the seat
cushions, e.g. knives, nails or tools. The
seats should only be occupied by passen-
gers, if possible. R
when the seat heating is in operation, do
not cover the seats with insulating materi- als, e.g. blankets, coats, bags, seat covers,
child seats or booster seats.
! Make sure that there are no objects in the
footwell under or behind the seats when mov-
ing the seats back. There is a risk that the
seats and/or the objects could be damaged.
i The head restraints in the front seats are
installed with the NECK-PRO system
( Y
page 55). For this reason, it is not possible
to remove the head restraints from the front
seats.
For more information, contact a qualified spe-
cialist workshop.
i Further related subjects: R
Rear bench seat through-loading feature
( Y
page 245)
Adjusting the seats electrically
C
Head restraint height D
Seat cushion angle

Adjusting the head restraints
Import ant safety notes
G WARNIN G
You could lose control of your vehicl e if you do
th e followin g while driving:R
adjust th e driver's seat , head restraint,
steering whee l or mirror sR
faste n th e seat belt
There is a ris k of an accident.
Adjus t th e driver's seat , head restraint, steer -
ing whee l and mirror and faste n your seat belt
before starting th e engine.
G WARNIN G
If th e head restraints are no t installed or no t
adjusted correctly, they canno t provid e pro -
tection as intended. There is an increased ris k
of injury in th e head and neck area, e.g. in th e
event of an acciden t or when braking .
Always drive wit h th e head restraints instal -
led. Befor e drivin g off , mak e sur e for every
vehicl e occupant that th e center of th e head
restrain t support s th e bac k of th e head at
about eye level.
Do no t rotate th e head restraints of th e fron t and
rear seats. Otherwise , you canno t adjust th e
height and angle of th e head restraints to th e
correc t position .
Using th e fore-and-af t adjustment, adjust th e
head restrain t so that it is as close as possibl e to
your head .
Observ e th e important safet y note s regarding
th e seat s ( Y
page 93). Adjusting the head restraint height
elect ri cally X
Slide switch for head restrain t height adjust -
men t C up or down in th e direction of th e
arrow.
Adjusting the luxury head restraints
X
To adjust th e sid e bolsters of th e hea d
restraint: push or pull right and/o r left-han d
side bolste r C int o th e desired position .X
To adjust th e angle of th e hea d restraint:
push or pull th e head restrain t in th e direction
of arrow D .
i Adjus t th e head restrain t so that th e bac k of
your head is as close to th e head restrain t as
possible.
Rear seat head restraints
Important safety notes
G WARNIN G
Fo r your protection , drive only wit h properly
positioned head restraints .
Adjus t th e head restraints so that they are as
close as possibl e to your head . This willSeats 95
Seats, steering wheel and mirrors Z