2018 MERCEDES-BENZ C-CLASS COUPE Owner's Manual

XRepeatedly tap theSmartKey against your
palm until battery =falls out .
XInsertth ene wbattery wit hth epositive ter-
minal facing upwards. Use alint-free cloth to
do so.
XMak esur ethat th esurfac eof th ebattery is
free of lint, grease and other contaminants.
XInser tth efron ttab sof battery compartmen t
cover :intoth ehousing first and then press
to close it .
XInsertmechanical ke y; intoth eSmartKey
(Ypage 77).
XChec kth efunction of all SmartKey buttons on
th evehicle.
Problems with the SmartKey
ProblemPossible causes/consequences and MSolutions
You can no longer lockor
unlock th evehicl eusin g
th eSmartKey.The SmartKey battery is discharged or nearly discharged.
XChec kth eSmartKey battery (Ypage 78) and replace it if necessar y
(Ypage 78).
If this does no twork:
XLoc kor unlock th evehicl eusin gth emechanical ke y (Ypage 82).
There is interferenc efrom apowerful source of radi owaves.
XLoc kor unlock th evehicl eusin gth emechanical ke y (Ypage 82).
The SmartKey is faulty.
XLockor unlock th evehicl eusin gth emechanical ke y (Ypage 82).
XHaveth eSmartKey checke dat aqualified specialist workshop.
You can no longer loc kor
unlock th evehicl eusin g
KEYLESS-GO .KEYLESS-GO was deactivated.
XReactivateKEYLESS-GO (Ypage 76).
The SmartKey battery is discharged or nearly discharged.
XCheckth eSmartKey battery (Ypage 78) and replace it if necessar y
(Ypage 78).
If this does no twork:
XLoc kor unlock th evehicl eusin gth emechanical ke y (Ypage 82).
There is interferenc efrom apowerful source of radi owaves.
XLoc kor unlock th evehicl eusin gth emechanical ke y (Ypage 82).
SmartKey79
Opening and closing
Z

ProblemPossible causes/consequences andMSolutions
KEYLESS-GO is malfunctioning.
XLock/unlock the vehicle using the remote control function of the
SmartKey.
XHave the vehicle and SmartKey checked at a qualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote con-
trol function:
XLock or unlock the vehicle using the mechanical key (Ypage 82).
XHave the vehicle and SmartKey checked at a qualified specialist
workshop.
The engine cannot be
started using the Smart-
Key.The on-board voltage is too low.
XSwitch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
XCheck the starter battery and charge it if necessary (Ypage 307).
or
XJump-start the vehicle (Ypage 308).
or
XConsult a qualified specialist workshop.
The engine cannot be
started using the Start/
Stop button. The Smart-
Key is in the vehicle.The vehicle is locked.
XUnlock the vehicle and try to start the vehicle again.
The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 78) and replace it if necessary
(Ypage 78).
If this does not work:
XStart your vehicle with the SmartKey in the ignition lock.
There is interference from a powerful source of radio waves.
XStart your vehicle with the SmartKey in the ignition lock.
You have lost a Smart-
Key.XHave the SmartKey deactivated at a qualified specialist workshop.
XReport the loss immediately to the vehicle insurers.
XIf necessary, have the locks changed as well.
You have lost the
mechanical key.XReport the loss immediately to the vehicle insurers.
XIf necessary, have the locks changed as well.
80SmartKey
Opening and closing

Doors
Important safet ynotes
GWARNING
If children are lef tunsupervised in th evehicle,
they could:
Rope nth edoors ,thus endangerin gother
people or road users.
Rget out and disrup ttraffic .
Roperat eth evehicle' sequipment.
Additionally, children could set th evehicle in
motion if, fo rexample, they:
Rrelease th eparking brake .
Rshiftingth eautomatic transmissio nout of
par kposition P
RStart theengine.
There is aris kof an acciden tand injury.
Whe nleavin gth evehicle, always take th e
SmartKey wit hyou and loc kth evehicle. Never
leav echildren or animals unattended in th e
vehicle. Always keep th eSmartKey out of
reach of children .
Unlockingan dopening doors from
th einside
You can ope n adoo rfrom insid eth evehicle
eve nif it has bee nlocked. If th evehicle has bee n
locke dwit hth eSmartKey or wit hKEYLESS-GO ,
opening adoo rfrom th einsid ewill trigger th e
anti-thef talar msystem. Switc hof fth ealar m
(
Ypage 74) .
XPull doorhandle ;.
If th edoo ris locked, locking knob :pop sup.
The doo ris unlocke dand opens .
Centrally locking an dunlocking th e
vehicle from th einside
You can centrall yloc kand unloc kth evehicle
from th einside. The switches are on th edriver’s
door.
XTo unlock :press butto n:.
XTo lock :press butto n;.
Whe nth efront-passenger doo ris closed, th e
vehicle is locked.
Meanwhile, th efue lfiller flap will no tbe locke d
or unlocked.
You canno tunloc kth evehicle centrall yfrom th e
insid eif th evehicle has bee nlocke dwit hth e
SmartKey or KEYLESS-GO .
The doors can be opene dfrom th einside.
If th evehicle has bee nlocke dwit hth eSmartKey
or wit hKEYLESS-GO ,opening adoo rfrom th e
insid ewill trigger th eanti-thef talar msystem.
Switc hof fth ealar m (
Ypage 74).
If alocke ddoo ris opene dfrom th einside, th e
previous unloc kstatus of th evehicle will be
take ninto consideration if:
Rth evehicle was locke dusin gth elocking but -
to nfo rth ecentral locking ,or
Rth evehicle was locke dautomatically
The vehicle will be full yunlocke dif it had previ-
ousl ybee nfull yunlocked. If only th edriver's
doo rhad bee npreviously unlocked, only th e
doo rwhic hhas bee nopene dfrom th einsid eis
unlocked.
Doors81
Opening and closing
Z

Automa tic locking featu re
XTo deactivate:press and hold butto n: for
approximately fiv eseconds until atone
sounds.
XTo activate: press and hold butto n; for
approximately fiv eseconds until atone
sounds.
If you press on eof th etwo buttons and do no t
hear atone ,th erelevan tsetting has already
been selected.
The vehicl eis locke dautomatically when th e
ignition is switched on and th ewheels are turn-
ing .
You could therefor ebe locke dout if:
Rth evehicl eis bein gpushed
Rth evehicl eis bein gtowed
Rth evehicl eis bein gtested on adynamometer.
You can activat eand deactivat eth eautomatic
locking mechanism via th emultimedia system
(see th eDigital Operator' sManual).
Locking/unlocking the driver's door
with the mechanical key
i
If you want to centrally loc kth evehicl eusin g
th emechanical key, begi nby pressing th e
locking butto nfor th einterior locking mech-
anism while th edriver's door is open .The n
loc kth edriver's door usin gth emechanical
key.
XInser tth emechanical ke yint oopening :in
th eprotective cap .
XPull and hold th edoor handle.
XPull th eprotective cap on th emechanical ke y
as straight as possibl eaway from th evehicl e
until it releases.
XReleas eth edoor handle.
XTo lock: turnth emechanical ke yclockwise as
far as it will go to position 1.
XTo unlock:turnth emechanical ke ycounter-
clockwise as far as it will go to position 1.
If you use th emechanical ke yto unloc kand
open th edriver's door ,th eanti-thef talarm sys-
te m will be triggered .Switc hoff th ealarm
(
Ypage 74) .
Trunk
Important safety notes
GWARNIN G
Combustion engines emi tpoisonous exhaust
gase ssuc has carbon monoxide. Exhaust
gase scan ente rth evehicl einterior if th e
trunk lid is open when th eengin eis running,
82Trunk
Opening and closing

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.
GWARNING
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
(
Ypage 349).
You can limit the opening angle of the trunk lid in
the multimedia system; see the Digital Opera-
tor's Manual.
Do not leave the SmartKey in the trunk. You
could otherwise lock yourself out.
You should preferably place luggage or loads in
the trunk. Observe the loading guidelines
(
Ypage 266).
Object detection with trunk lid revers-
ing feature
Vehicles with trunk lid remote closing fea-
ture:
The trunk lid is equipped with automatic object
detection with a reversing feature. If a solid
object blocks or restricts the trunk lid when
automatically opening, this procedure is stop-
ped. If a solid object blocks or restricts the trunk
lid when automatically closing, the trunk lid
opens again automatically. Automatic object
detection with reversing function is only an aid.
It is not a substitute for your attentiveness when opening and closing the trunk lid.
GWARNING
The reversing feature does not respond:
Rto soft, light and thin objects, e.g. fingers
Rover 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:
Rpress the Fbutton on the SmartKey, or
Rpull or press the remote operating switch
on the driver's door or
Rpress the closing or locking button on the
trunk lid
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
XPress the Fbutton on the SmartKey.
The trunk lid opens.
Closing
Trunk83
Opening and closing
Z

XPull the trunk lid down using recess:and
push it closed.
XLock the vehicle if necessary with the &
button on the SmartKey or with KEYLESS-GO
(
Ypage 76).
Opening/closing automatically from
outside
Important safety notes
GWARNING
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.
GWARNING
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:
Rpress the Fbutton on the SmartKey.
Rpull or press the remote operating switch
on the driver's door.
Rpress the closing or locking button on the
trunk lid.
Vehicles with HANDS-FREE ACCESS:
It is also possible to stop the closing process by
performing a kicking movement under the rear
bumper.
!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
(
Ypage 349).
Opening automatically
You can open the trunk lid automatically using
the SmartKey.
XPress and hold the
Fbutton on the Smart-
Key until the trunk lid opens.
Closing automatically
:Closing button
;Locking button
XPress closing button :in the trunk lid.
Vehicles with trunk lid remote closing fea-
ture and KEYLESS-GO: when the driver's door
is closed you can simultaneously close the trunk
lid and lock the vehicle. To do this, the SmartKey
must be in the KEYLESS-GO detection range to
the rear of the vehicle.
XPress locking button ;in the trunk lid.
If KEYLESS-GO detects a SmartKey outside
the vehicle, the trunk lid closes. The vehicle is
locked.
If KEYLESS-GO detects a SmartKey in the trunk,
the trunk lid opens again after it is closed.
If KEYLESS-GO detects a second SmartKey out-
side the vehicle, the trunk lid remains closed.
If KEYLESS-GO detects a SmartKey in the trunk
before the closing procedure starts, the trunk lid
remains open.
84Trunk
Opening and closing

HANDS-FREE ACCESS
General notes
With KEYLESS-GO and HANDS-FREE ACCESS,
you can open or close the trunk lid or stop the
procedure without using your hands. This is use-
ful if you have your hands full. To do this, make
a kicking movement under the bumper with your
foot.
Observe the following points:
RCarry your KEYLESS-GO key about your per-
son. The SmartKey must be at the rear of the
vehicle in the detection range of KEYLESS-
GO.
RWhen making the kicking movement, make
sure that you are standing firmly on the
ground and that there is sufficient clearance
to the rear of the vehicle. You could otherwise
lose your balance, for example on ice.
RAlways ensure that you only make the kicking
movement within the detection range of sen-
sors :.
RStand at least 12 in (30 cm) away from the
rear area while doing so.
RDo not come into contact with the bumper
while making the kicking movement. Other-
wise, the sensors may not function correctly.
RHANDS-FREE ACCESS does not function dur-
ing engine start.
RDirt caused by road salt or snow around sen-
sors:may restrict functionality.
Using the HANDS-FREE ACCESS with a pros-
thetic leg may restrict functionality.
RIf a KEYLESS-GO key is at the rear of the vehi-
cle in the detection range of KEYLESS-GO,
HANDS-FREE ACCESS could be triggered. The trunk lid could thus be opened or closed
unintentionally, for example, if you:
-sit on the edge of the trunk.
-set something down or lift something up
behind the vehicle.
-polish the rear of the vehicle.
Do not carry the KEYLESS-GO key about your
person in these situations or in situations sim-
ilar to these. This will prevent unintentional
opening or closing of the trunk lid.
Important safety notes
GWARNING
The vehicle exhaust system can become very
hot. If you use HANDS-FREE ACCESS, you
could burn yourself by touching the exhaust
system. There is a risk of injury. Always
ensure that you make the kicking movement
only within the detection range of the sensors.
!If the SmartKey is within the rear detection
range of KEYLESS-GO, the following situa-
tions, for example, could lead to the uninten-
tional opening of the trunk lid:
Rwhen using an automatic car wash
Rwhen using a power washer
Make sure that the SmartKey is at least 10 ft
(3 m) away from the vehicle.
Operation
XTo open or close: kick with your foot into
sensor detection range :beneath the
bumper.
A warning tone will sound while the trunk lid is
opening or closing.
XIf the trunk lid does not open or close after
several attempts: wait at least ten seconds
Trunk85
Opening and closing
Z

then move your leg under the bumper once
again.
If you hold your foot under the bumper for too
long, the trunk lid does not open or close.
Repeat the leg movement more quickly if this
occurs.
To stop the opening or closing procedure, you
have the following options:
RKick with your foot into sensor detection
range :beneath the bumper.
RPress the closing button on the trunk lid.
RPress the Fbutton on the SmartKey.
If the trunk lid closing procedure has been stop-
ped:
RMove your foot under the bumper again and
the trunk lid will open.
If the trunk lid opening procedure has been
stopped:
RMove your foot under the bumper again and
the trunk lid will close.
Opening/closing automatically from
inside
Important safety notes
GWARNING
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.
GWARNING
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.
Vehicles with HANDS-FREE ACCESS:
It is also possible to stop the closing process by
performing a kicking movement under the rear
bumper.
!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
(
Ypage 349).
Opening and closing
XTo open: pull remote operating switch :for
the trunk lid until the trunk lid opens.
XTo close: press and hold remote operating
switch :for the trunk lid until the trunk lid is
completely closed.
When the vehicle is stationary, you can close the
trunk lid from the driver's seat. When the vehicle
is also unlocked, you can also open the trunk lid
from inside.
Locking the trunk separately
You can lock the trunk separately. If you then
unlock the vehicle centrally, the trunk remains
locked and cannot be opened.
86Trunk
Opening and closing