2018 MERCEDES-BENZ CLS ignition

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

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

X
Make sure that all the side windows and the
sliding sunroof are closed. X
Make sure that all the side windows are
closed. X
To interrupt convenience closing: release
the 7 button.
Using KEYLESS-GO The driver's door and the door at which the han-
dle is used, must both be closed. The SmartKey
must be outside the vehicle. The gap between
the SmartKey and the corresponding door han-
dle should not be greater than 3 ft (1 m).
X
Touch recessed sensor surface C on the
door handle until the side windows and the
sliding sunroof are fully closed. X
Touch recessed sensor surface C on the
door handle until the side windows are fully
closed.
i Make sure you only touch recessed sensor
surface C . X
Make sure that all the side windows and the
sliding sunroof are closed. X
Make sure that all the side windows are
closed. X
To interrupt convenience closing: release
recessed sensor surface C on the door han-
dle.
Resetting the side windows If a side window can no longer be closed fully,
you must reset it. X
Close all the doors. X
Turn the SmartKey to position 1 or 2 in the
ignition lock. X
Pull the corresponding switch on the door
control panel until the side window is com-
pletely closed ( Y
page 87). X
Hold the switch for an additional second.
If the side window opens again slightly: X
Immediately pull the corresponding switch on
the door control panel until the side window is
completely closed ( Y
page 87).X
Hold the switch for an additional second. X
If the respective side window remains closed
after the button is released, then it has been
set correctly. If this is not the case, repeat the
steps above again.
Problems with the side windows
G WARNING
If you close a side window again immediately after it has been blocked or reset, the side window
closes with increased or maximum force. The reversing feature is then not active. Parts of the
body could be trapped in the closing area in the process. This poses an increased risk of injury or
even fatal injury.
Make sure that no parts of the body are in the closing area. To stop the closing process, release
the switch or push the switch again to reopen the side window. Side windows 89
Opening and closing Z

X
Turn the SmartKey to position 2 in the ignition
lock ( Y
page 123).
Adjusting the active multicontour
seat The active multicontour seat is only available for
the driver's side.
You can adjust the active multicontour seat via
the multimedia system (see the Digital Opera-
tor's Manual).
Adjusting the 4-way lumbar support
C
To raise the backrest contourD
To soften the backrest contour

Switching the seat ventilation on/off
Driver's and front-passenger seat
The three blue indicator lamps in the buttons
indicate the ventilation level you have selected. X
Turn the SmartKey to position 1 or 2 in the
ignition lock ( Y
page 123). X
To switch on: press button C repeatedly
until the desired ventilation level is set. X
To switch off: press button C repeatedly
until all the indicator lamps go out.
i If the battery voltage is too low, the seat
ventilation may switch off.
i You can open the side windows and the slid-
ing sunroof using the "Convenience opening"
feature ( Y
page 88). The seat ventilation of
the driver's seat automatically switches to the
highest level.
Problems with the seat heating or seat ventilation Problem
Possible causes/consequences and P Solutions
The seat heating or seat
ventilation has switched
off prematurely or can-
not be switched on. The on-board voltage is too low because too many electrical consum-
ers are switched on. X
Switch off electrical consumers that you do not need, such as the
rear window defroster or interior lighting.
Once the battery is sufficiently charged, the seat heating or seat
ventilation can be switched back on manually.
Steering wheel
Important safety notes
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
Children could injure themselves if they
adjust the steering wheel. 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.
The electrically adjustable steering wheel can
still be adjusted when there is no SmartKey in
the ignition lock.98
Steering wheel
Seats, steering wheel and mirrors