2018 MERCEDES-BENZ SLC child lock

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 253).
or X
Jump-start the vehicle ( Y
page 253).
or X
Consult aq ualified 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.
The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 68) and replace it if necessary
( Y
page 68).
If this does not work: X
Start your vehicle with the SmartKey in the ignition lock.
There is interference from ap owerful source of radio waves.X
Start your vehicle with the SmartKey in the ignition lock.
You have lost aS mart-
Key. X
Have the SmartKey deactivated at aq ualified 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.
The side windows cannot
be opened or closed
using the convenience
opening/closing fea-
ture. The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 68) and replace it if necessary
( Y
page 68).
Doors
Important safety notes
G WARNING
If children are left unsupervised in the vehicle,
they could: R
operate the vehicle's equipment. Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake R
shift the automatic transmission out of park
position P R
start the engine
There is ar isk of an accident and injury.
Never leave children or animals unattended in
the vehicle.70
Doors
Opening and closing

tion H .S imultaneousl yp ul lt he trunk li dh an -
dle.
The trunk is unlocked. X
Turn the mechanica lk ey back to position G
and remove it. X
Insert the mechanica lk ey into the SmartKey.
Emergenc yr elease fo rt he trunkYo uc an unlock the trunk li df ro mt he insid ew it h
the emergency release button.
X
Press emergency release button C briefly.
The trunk li du nlocks and opens.
The trunk li dc an be unlocke da nd opene dw it h
the trunk li de mergency release when the vehi-
cle is stationar yorw hile driving.
The trunk li de mergency release does not unlock
the trunk li dift he battery is disconnecte do r
discharged.
Trunk li de mergency release light:R
Emergency release button C flashe sf or
30 minute sa ft er the trunk li diso pe nedR
Emergency release button C flashe sf or
60 minute sa fter the trunk li disc losed
Side windows
Important safety notes
G WARNING
Whil eo pe ning the side windows ,b od yp ar ts
could become trapped between the side win-
do wa nd the door frame as the side window
moves .T here is ar is kofi njury.
Make sure tha tn obod yt ouche st he side win-
do wd ur in gt he opening procedure. If some- body become st rapped ,r elease the switch or
pull the switch to close the side windo wa gain .
G WARNING
Whil ec losing the side windows ,b od yp ar ts in
the closing area could become trapped .T here
is ar is kofi njury.
When closing make sure tha tnop ar ts of the
body ar eint he closing area .Ifs omebody
become st rapped ,r elease the switch or press
the switch to open the side windo wa gain .
G WARNING
If children operate the side windows they
could become trapped ,p ar ticularly if the ya re
left unsupervised .T here is ar is kofi njury.
When leaving the vehicle, always take the
SmartKe yw it hy ou and lock the vehicle. Never
leav ec hildren unsupervised in the vehicle.
Side windo wr eversin gf ea tureThe front side windows ar ee quippe dw it ha n
automatic reversing feature. If as olid object
blocks or restricts the upward movement of one
of the front side windows durin gt he closing
process, the side windo wo pe ns agai na ut omat-
ically. During the manua lc losing process, the
side windo wo nl yo pe ns agai na ut omatically
after the corresponding switch is released. How-
ever, the automatic reversing featur eiso nl ya n
ai da nd does not relieve yo uoft he responsibility
of paying attentio nw he nc losing as id ew in dow.
G WARNING
The reversing featur ed oe sn ot react:R
to soft, light and thi no bj ects ,e .g .s mall fin-
gers R
ove rt he last 1/6 in(4 mm) of the closing
movement R
durin gr esetting R
when closing the side windo wa gain man-
uall yi mm ediatel ya ft er automatic reversing
Thi sm eans tha tt he reversing featur ec annot
prevent someone being trapped in these sit-
uations. There is ar is kofi njury.74
Side windows
Openin ga nd closing

The seats can still be adjusted when there is no
SmartKey in the ignition lock.
G WARNING
When you adjust as eat, you or other vehicle
occupant sc ould become trapped, e.g. on the
seat guide rail. There is ar isk of injury.
Make sure when adjusting as eat that no one
has any body parts in the sweep of the seat.
G WARNING
If the driver's seat is not engaged, it could
move forwards as far as the next catc hd uring
movemen ts uch as braking or abrupt changes
of direction .Asar esult, you would be pushed
against your seat belt by the unsecured driv-
er's seat.
This could cause you to lose control of the
vehicle. The seat belt cannot protec tasi nten-
ded and could result in additional injury.
There is ar isk of an accident and injury.
Before every journey, make sure that the driv-
er's seat is fully engaged.
Observe the safety notes on "Air bags"
( Y
page 43) and "Children in the vehicle"
( Y
page 53).
G WARNING
If the driver's seat is not engaged, it could
move unexpectedly while the vehicle is in
motion .T his could cause you to lose control of
the vehicle. There is ar isk of an accident.
Always make sure that the driver's seat is
engaged before starting the vehicle.
G WARNING
If you adjust the seat height carelessly, you or
other vehicle occupant sc ould be trapped and
thereby injured. Children in particular could
accidentally press the electrical seat adjust-
ment button sa nd 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 adjustmen ts ys-
tem. G WARNING
If the head restraints are not installed or not
adjusted correctly, they cannot provide pro-
tection as intended. There is an increased risk
of injury in the head and neck area, e.g. in the
event of an accident or when braking.
Always drive with the head restraints instal-
led. Before driving off, make sure for every
vehicle occupant that the center of the head
restraint supports the back of the head at
about eye level.
G WARNING
You could lose control of your vehicle if you do
the following while driving: R
adjust the driver's seat, head restraint,
steerin gw heel or mirrors R
fasten the seat belt
There is ar isk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt
before starting the engine.
! To prevent damage to the seats and the seat
heating, observe the following notes: R
Do not spill liquids ont ot he seats. Dry the
seats as soon as possible if liquid does get
spilled on the seats. R
If the seat covers are damp or wet, do not
switch on the seat heating. Also, do not use
the seat heating to dry the seats. R
Clean the seat covers as recommended;
see the "Interior care" section. R
Do not transport heavy loads on the seats.
Do not place pointed object sont he seat
cushions such as knives, nails or tools.
Where possible, use the seats only for car-
rying passengers. R
When operating the seat heating, do not
cover the seats with insulating materials,
e.g. blankets ,c oats, bags, protective cov-
ers, child seats or booster seats. R
When the seat heating is switched on, the
seat surface can be damaged as ar esult of
object sb eing placed on the seats; for
example, seat cushions, child seats and
protective covers not approved by
Mercedes-Benz. Seats 85
Seats, steering wheel and mirrors Z

This could result in burns in the immediate
vicinit yoft he air vents. There is ar isk of injury.
Reduce the heater output before it becomes
too hot.
The AIRSCARF function warms the head and
neck area of vehicle occupant sw ith warm air.
The warm air flows out of the holes in the head
restraints.
The three red indicator lamps in the button indi-
cate the heating level you have selected. X
Ensure that the SmartKey is in position H in
the ignition lock. X
To switch on: press button C .
Three red indicator lamps in the button light
up. The blower start supa fter ap reheating
phase of seven seconds. X
Press button C repeatedly until the desired
heating level is set. X
To switch off: press button C repeatedly
until all the indicator lamps go out.
i The blower continues runnin gf or seven sec-
onds to cool down the heating elements.
i If the battery voltage is too low, AIRSCARF
may switch off.
Problems with AIRSCARF AIRSCARF has switched off prematurely or will
not switch on. The vehicle's electrical system
voltage is too low because too many electrical
consumer sa re switched on.X
Switch off electrical consumer st hat you do
not need, such as the rear window defroster
or interior lighting. X
Switch on AIRSCARF again. 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,
steerin gw heel or mirrors R
fasten the seat belt
There is ar isk 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 steerin gw heel. There is ar isk of
injury.
When leaving the vehicle, alway st ake the
SmartKey with you and lock the vehicle. This
also applies to mobile phones if the "Digital
Car Key in smartphone" function is activated
via the Mercedes me connect web app. Never
leave children unsupervised in the vehicle.
The electrically adjustable steerin gw heel can
still be adjusted when there is no SmartKey in
the ignition lock.
Adjusting the steering wheel man-
ually
G WARNING
If the steerin gw heel is unlocked while the
vehicle is in motion ,itc ould change position
unexpectedly. This could cause you to lose
control of the vehicle. There is ar isk of an
accident.
Before starting off, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion.88
Steering wheel
Seats, steering wheel and mirrors

As soo na st he ignition is switched on, al lt he
indicator lamps in the instrument cluster light
up .F urther informatio nons it uations where an
indicator lamp either fails to go ou ta fte rs tarting
the engine or lights up whil ed riving
( Y
page 204).
If Start/Stop button C ha sn ot ye tb ee n
pressed, thi sc orrespond stot he key being
remove df rom the ignition.X
To switc hont he power supply: press
Start/Stop button C once.
The powe rs uppl yiss wi tched on. Yo uc an now
activate the windshield wipers, for example.
The powe rs uppl yiss wi tched off agai ni f:R
the driver's door is opene da ndR
yo up ress Start/Stop button C twice when
in thi sp ositionX
To switc hont he ignition: press Start/Stop
button C twice.
The ignition is switched on.
If yo up ress Start/Stop button C once when
in thi sp osit ion, the ignition is switched off
again.
Removing the Start/Sto pb uttonYo uc an remove the Start/Stop button from the
ignition lock and start the vehicl easn ormal
using the SmartKey. X
Remove Start/Stop button C from ignition
lock D .
Yo udon ot have to remove the Start/Stop but-
ton from the ignition lock when yo ul eave the
vehicle. Yo us hould, however, always take the
SmartKe yw it hy ou when leaving the vehicle. As
long as the Sma rtKe y isint h
e vehicle:R
the vehicl ec an be started using the Start/
Stop button R
the electrically powered equipment can be
operated
Starting the engine
Important safety notes
G WARNING
If children ar el ef tu nsupervised in the vehicle,
they could: R
operate the vehicle's equipment. Additionally, children could set the vehicl ei n
motion if, for example, they: R
release the parking brake R
shift the automatic transmission ou tofp ar k
position P R
start the engine
There is ar is kofana ccident and injury.
Never leav ec hildren or animals unattended in
the vehicle.
Whe nl eavi ng the vehicle, always take the
SmartKe yw it hy ou and lock the vehicle. This
also applie stom obil ep hones if the "Digital
Ca rK ey in smartphone "f un ctio ni sa ctivated
via the Mercedes me connect we ba pp .
G WARNING
Combustion engine se mi tp oiso nou se xhaust
gases such as carbo nm onoxide. Inhaling
thes ee xhaus tg as es lead stop oiso ning. There
is ar is koff ata li njury .T herefore neve rl eave
the engine running in enclose ds paces with-
ou ts uf ficient ventilation.
G WARNING
Flammabl em at erial si ntroduced through
environmenta li nfluence or by animals can
ignite if in contact with the exhaus ts ys tem or
parts of the engine tha th ea tu p. There is ar isk
of fire.
Carry ou tr egular checks to make sure that
ther ea re no flammabl ef oreig nm at erial si n
the engine compartment or in the exhaust
system.
During ac ol ds tart, the engine runs at higher
speed stoe nabl et he catalytic converter to
reach its operating temperature .T he sound of
the engine ma yc hange during thi st ime.
Automati ct ransmission X
Depres st he brake peda la nd kee pi t
depressed. X
Shift the transmission to position ] .
Transmission positio nd is play ] is shown in
the multifunctio nd is play.Driving 117
Driving an dp arking Z

The current transmission position and drive pro-
gram appear in the multifunction display.
Mercedes-AMG SLC 43
C
Transmission positionD
Drive program
The current transmission position and drive pro-
gram appear in the multifunction display.
Engaging par kp osition P
X
When the vehicle is stationary, depress the
brake pedal. X
Press button C .
Engaging par kp osition Pa utomaticallyPark position ] is automatically engaged if:R
you switch off the engine using the SmartKey
and remove the SmartKey R
you switch off the engine using the SmartKey
or using the Start/Stop button and open the
driver's door or front-passenger door R
you open the driver's door when the vehicle is
stationary or when driving at av ery low speed
and the transmission is in position [ or ^
Under certain conditions, the automatic trans-
mission shifts automatically to transmission
position ] if the HOLD function or Distance
Pilot DISTRONIC is activated. Observe the infor-
mation on the HOLD function ( Y
page 148) and
on Distance Pilot DISTRONIC ( Y
page 144). Engaging reverse gear R
! Only move the automatic transmission to
^ when the vehicle is stationary. X
Depress the brake and keep it pressed. X
Push the selector lever forwards past the first
point of resistance.
The ECO start/sto pf unction is not available
when reverse gear is engaged. Further informa-
tion on the ECO start/sto pf unction
( Y
page 119).
Shifting to neutral N
G WARNING
If children are left unsupervised in the vehicle,
they could: R
operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake R
shift the automatic transmission out of park
position P R
start the engine
There is ar isk of an accident and injury.
Never leave children or animals unattended in
the vehicle.
When leaving the vehicle, alway st ake the
SmartKey with you and lock the vehicle. This
also applies to mobile phones if the "Digital
Car Key in smartphone" function is activated
via the Mercedes me connect web app. X
When the vehicle is stationary, depress the
brake pedal. X
Push the selector lever forwards or back to
the first point of resistance.
If you switch the engine off with the transmis-
sion in position ^ or [ ,t he automatic trans-
mission shifts to \\ automatically.
With the SmartKey: if you then open the driv-
er's door or the front-passenger door or remove
the SmartKey from the ignition, the automatic
transmission shifts to ] automatically.
With KEYLESS-GO: if you then open the driver's
or front-passenger door, the automatic trans-
mission shifts to ] automatically.Automatic transmission 123
Driving and parking Z

X
Press the d or c button to select the
Automatic Door Lock function.
When the Automatic Door Lock function is
activated, the multifunction display shows the
left-hand vehicle door in orange. X
Press the v button to save the setting.
For further information on the automatic locking
feature, see ( Y
page 71).
Activating/deactivating the acoustic
locking verification signal If you switch on the Acoustic Lock function, an
acoustic signal sounds when you lock the vehi-
cle. X
Press the Y or e button on the steering
wheel to select the Sett. menu.X
Press the d or c button to select the
Vehicle submenu.X
Press v to confirm.X
Press the d or c button to select the
Acoustic Lock function.
If the Acoustic Lock function is activated,
the 7 symbol in the multifunction display
lights up orange. X
Press the v button to save the setting.
Comfort
Activating/deactivating the EASY-
ENTRY/EXI Tf eature
G WARNING
When the EASY-ENTRY/EXIT feature adjusts
the steerin gw heel, you and other vehicle
occupant s–p articularly children –c ould
become trapped. There is ar isk of injury.
While the EASY-ENTRY/EXIT feature is mak-
ing adjustments, make sure that no one has
any body parts in the sweep of the steering
wheel.
If somebody becomes trapped: R
press one of the memory function position
buttons, or R
move the switch for steerin gw heel adjust-
ment in the opposite direction to that in
which the steerin gw heel is moving.
The adjustmen tp rocess is stopped. X
Press the Y or e button on the steering
wheel to select the Sett. menu.X
Press the d or c button to select the
Convenience submenu. X
Press v to confirm. X
Using d or c ,s elect the Easy Entry/
Exit function.
If the Easy Entry/Exit function is activated,
the multifunction display shows the steering
wheel in orange. X
Press the v button to save the setting.
Further information on the EASY-ENTRY/EXIT
feature ( Y
page 89).
Switching the seat belt adjustment on/off X
Press the Y or e button on the steering
wheel to select the Sett. menu.X
Press the d or c button to select the
Convenience submenu. X
Press v to confirm. X
Press the d or c button to select the
Belt Adjustment function.
When the Belt Adjustment function is acti-
vated, the seat belt is displayed in orange in
the multifunction display. X
Press the v button to save the setting.
For further information on belt adjustment, see
( Y
page 42).
Switching the fold-in mirrors when lock-
ing feature on/off This function is only availabl ew hen the vehicle is
equipped with the electrical fold-in function.
This function is only availabl einC anada.
When you activat et he Auto. Mirror Folding
function, the exterior mirrors are folded in when
the vehicle is locked.
If you have switched on the Auto. Mirror
Folding function and you fold in the exterior
mirrors using the button on the door
( Y
page 91), they will not fold out automatically.
The exterior mirrors can then only be folded out
using the button on the door. X
Press the Y or e button on the steering
wheel to select the Sett. menu.X
Press the d or c button to select the
Convenience submenu. X
Press v to confirm.174
Menus and submenus
On-board computer and displays

rubbish. They must be col-
lected separately and dis-
posed of in an environmen-
tall yr esponsible recycling
system.
Dispose of batterie sina n
environmentally responsi-
ble manner. Take dis-
charge db atterie stoaq uali-
fied specialist workshop or
to ac ollection point for
used batteries.
! Have the battery checked regularl yata
qualified specialist workshop.
Observe the service interval sint he Mainte-
nance Booklet or contact aq ualified specialist
workshop for more information.
! Always have work on batterie sc arrie do ut at
aq ualified specialist workshop.
Shoul di t, in exceptiona lc ircumstances, be
absolutel yn ecessary to disconnect the 12-
volt battery yourself, please observe the fol-
lowing: R
Secure the vehicl etop revent it from rolling
away. R
Switch off the ignition. R
Disconnect the negative terminal first and
then the positive terminal.
The transmission is locked in position ]
after disconnecting the battery.
After the work has been done, install the bat-
tery and replace the cover of the positive ter-
minal clamp firmly.
Comply with safety precautions and take pro-
tective measures when handling batteries.
Ris kofe xplosion.
Fire, open flame sa nd smoking are
prohibited when handling the bat-
tery. Avoid creating sparks.
Battery acid is caustic. Avoid contact
with skin, eye sorc lothing.
Wea rs uitable protective clothing,
especially gloves, apro na nd face-
guard. Rinse any acid spills immediately
with clea rw ater. Contact ap hysician
if necessary.
Wea re ye protection.
Keep children away.
Observe this Operator's Manual.
For safety reasons, Mercedes-Benz recom-
mends that you only use batterie sw hich have
been tested and approved for you rv ehicl eb y
Mercedes-Benz. These batterie sp rovide
increase di mpact protection to prevent vehicle
occupants from suffering acid burns should the
battery be damaged in the event of an accident.
In order for the battery to achieve the maximum
possible service life ,itm ust alway sbes uffi-
ciently charged.
Like other batteries, the vehicl eb attery may
discharge over time if you do not use the vehicle.
In this case, have the battery disconnected at a
qualified specialist workshop .Y ou can also
charge the battery with ac harge rr ecommended
by Mercedes-Benz. Contact aq ualified special-
ist workshop for further information.
Have the battery condition of charge checked
more frequently if you use the vehicl em ainl yf or
short trips or if you leave it standing idl ef or a
lengthy period. Consult aq ualified specialist
workshop if you wis htol eave you rv ehicle
parked for al ong perio doft ime.
Remove the SmartKey if you park the vehicle
and do not require any electrica lc onsumers.
The vehicl ew il lt hen use very little energy ,t hus
conserving battery power.
If the powe rs upply has been interrupted ,e .g. if
you reconnect the battery ,y ou wil lh ave to:R
reset the function for automatically folding
the exterior mirrors in/out by folding the mir-
rors out once ( Y
pag e9 1)R
set the clock
On vehicles with am ultimedia system, the
time is set automatically.252
Battery (vehicle)
Breakdown assistance