keyless MERCEDES-BENZ C-CLASS CABRIOLET 2018 Owner's Manual

Selecting displays .......................... 206
Setting the position ....................... 206
Storing settings (memory func-
tion) ............................................... 106
Switching on or off ......................... 195
Headlamps
Display message ............................ 224
Fogging up ..................................... 110
see Automatic headlamp mode
Heating
see Climate control
High beam flasher ............................. 108
High-beam headlamps
Adaptive Highbeam Assist ............. 109
Display message ............................ 224
Switching on/off ........................... 108
Hill start assist .................................. 127
HOLD function
Activating ....................................... 162
Activation conditions ..................... 161
Deactivating ................................... 162
Display message ............................ 231
Function/notes ............................. 161
General notes ................................ 161
Home address
see also Digital Operator's Man-
ual .................................................. 253
Hood
Closing ........................................... 282
Display message ............................ 238
Important safety notes .................. 281
Opening ......................................... 281
Horn ...................................................... 35
HUD
see Head-up display
Hydroplaning ..................................... 150
I
Ignition key
see SmartKey
Ignition lock
see Key positions
Immobilizer .......................................... 74
Indicator lamps
see Warning and indicator lamps
Indicators
see Turn signals Insect protection on the radiator
.... 282
Inspection
see ASSYST PLUS
Instrument cluster
Overview .......................................... 36
Warning and indicator lamps ........... 36
Instrument cluster lighting .............. 192
Interior lighting
Automatic control .......................... 111
Control ........................................... 111
Overview ........................................ 110
Reading lamp ................................. 110
iPod
®
see also Digital Operator's Man-
ual .................................................. 253
J
Jack Using ............................................. 333
Jump starting (engine) ...................... 304
K
Key positions
SmartKey ....................................... 123
Start/Stop button .......................... 124
KEYLESS-GO
Activating ......................................... 77
Deactivation ..................................... 77
Locking ............................................ 77
Removing the Start/Stop button ... 124
Start function ................................... 77
Unlocking ......................................... 77
Kickdown
Driving tips .................................... 136
Manual gearshifting ....................... 141
Knee bag .............................................. 50
L
Lamps
see Warning and indicator lamps
Lane Change Assist
see Active Blind Spot Assist
Lane detection (automatic)
see Lane Keeping Assist
Lane Keeping Assist
Activating/deactivating ................. 185
Index13

Adjusting the 4-way lumbar sup-
port .................................................. 98
Adjusting the head restraint ............ 96
Calling up a stored setting (mem-
ory function) .................................. 106
Cleaning the cover ......................... 294
Folding the backrest (rear com-
partment) forwards/back .............. 265
Folding the backrests forward/
back ................................................. 97
Important safety notes .................... 94
Seat backrest display message ..... 238
Seat heating .................................... 99
Seat heating problem .................... 100
Seat ventilation ................................ 99
Seat ventilation problem ................ 100
Storing settings (memory func-
tion) ............................................... 106
Switching AIRSCARF on/off .......... 100
Securing a load
see Securing cargo
Securing cargo .................................. 266
Selecting a gear
see Automatic transmission
Selector lever
Cleaning ......................................... 293
see Automatic transmission
Sensors (cleaning instructions) ....... 292
Service center
see Qualified specialist workshop
Service Center
see Qualified specialist workshop
Service menu (on-board com-
puter) .................................................. 203
Service message
see ASSYST PLUS
Service products
Brake fluid ..................................... 343
Coolant (engine) ............................ 343
Engine oil ....................................... 342
Fuel ................................................ 340
Important safety notes .................. 340
Refrigerant (air-conditioning sys-
tem) ............................................... 344
Washer fluid ................................... 344
Setting the date/time format
see also Digital Operator's Man-
ual .................................................. 253 Setting the language
see also Digital Operator's Man-
ual .................................................. 253
Setting the time
see also Digital Operator's Man-
ual .................................................. 253
Se

ttings
Factory (on-board computer) ......... 207
On-board computer ....................... 203
SETUP (on-board computer,
Mercedes-AMG vehicles) .................. 209
Side impact air bag ............................. 50
Side marker lamp (display mes-
sage) ................................................... 224
Side windows
Cleaning ......................................... 291
Important safety information ........... 85
Opening/closing .............................. 86
Opening/closing (all) ....................... 86
Problem (malfunction) ..................... 87
Resetting ......................................... 87
Reversing feature ............................. 85
SIRIUS services
see also Digital Operator's Man-
ual .................................................. 253
SmartKey
Changing the battery ....................... 79
Changing the programming ............. 78
Checking the battery ....................... 79
Display message ............................ 240
Door central locking/unlocking ....... 76
Important safety notes .................... 76
KEYLESS-GO start function .............. 77
Loss ................................................. 80
Mechanical key ................................ 78
Opening/closing soft top ................. 90
Overview .......................................... 76
Positions (ignition lock) ................. 123
Problem (malfunction) ..................... 80
Starting the engine ........................ 125
Smartphone
Starting the engine ........................ 126
SMS
see also Digital Operator's Man-
ual .................................................. 253
Snow chains ...................................... 315
Socket (12 V)
Center console .............................. 270
Index19

Panic alarm
XTo arm:press and hold !button :for
approximately one second.
A visual and audible alarm is triggered if the
alarm system is armed.
XTo disarm: press!button :again.
or
XInsert the SmartKey into the ignition lock.
or
XVehicles with KEYLESS-GO start function
or KEYLESS-GO: press the Start/Stop but-
ton.
The SmartKey must be in the vehicle.
Occupant safety
Introduction to the restraint system
The restraint system can reduce the risk of vehi- cle occupants coming into contact with parts of
the vehicle's interior in the event of an accident.
The restraint system can also reduce the forces to which vehicle occupants are subjected during
an accident.
The restraint system comprises:
RSeat belt system
RAir bags
RChild restraint system
RChild seat securing systems
The components of the restraint system work in
conjunction with each other. They can only
deploy their protective function if, at all times, all
vehicle occupants:
Rhave fastened their seat belts correctly
(Ypage 46)
Rhave the seat and head restraint adjusted
properly (Ypage 94) As the driver, you also have to make sure that
the steering wheel is adjusted correctly.
Observe the information relating to the correct
driver's seat position (
Ypage 94).
You also have to make sure that an air bag can
inflate properly if deployed (
Ypage 49).
An air bag supplements a correctly worn seat
belt. As an additional safety device, the air bag
increases the level of protection for vehicle
occupants in the event of an accident. For exam-
ple, if, in the event of an accident, the protection
offered by the seat belt is sufficient, the air bags
are not deployed. When an accident occurs, only
the air bags that increase protection in that par- ticular accident situation are deployed. How-
ever, seat belts and air bags generally do not
protect against objects penetrating the vehicle
from the outside.
Information on restraint system operation can
be found under "Triggering of the Emergency
Tensioning Devices and air bags" (
Ypage 56).
See "Children in the vehicle" for information on
children traveling with you in the vehicle as well
as on child restraint systems (
Ypage 59).
Important safety notes
GWARNING
Modifications to the restraint system may
cause it to no longer work as intended. The
restraint system may then not perform its
intended protective function and may fail in an
accident or trigger unexpectedly, for example.
This poses an increased risk of injury or even fatal injury.
Never modify parts of the restraint system.
Never tamper with the wiring, the electronic
components or their software.
If it is necessary to modify components of the
restraint system to accommodate a person with
disabilities, contact an authorized Mercedes-
Benz Center for details. USA only: for further
information contact our Customer Assistance
Center at 1-800-FOR-MERCedes
(1‑800‑367‑6372).
Mercedes-Benz recommends that you only use
driving aids which have been approved specifi-
cally for your vehicle by Mercedes-Benz.
Occupant safety43
Safety
Z

Up to a speed of approximately 44 mph
(70 km/h) the Active Brake Assist with cross-
traffic function assists you with braking in haz-
ardous situations with:
Rstationary obstacles in the path of the vehicle,
e.g. stopped or parked vehicles
Rstationary pedestrians in the path of the vehi-
cle
Robstacles crossing your path that move in the
detection range of the sensors and are detec-
ted
XKeep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
You can prevent the intervention of Active Brake
Assist with cross-traffic function at any time by:
Rdepressing the accelerator pedal further.
Ractivating kickdown.
Rreleasing the brake pedal
The braking application of Active Brake Assist
with cross-traffic function is ended automati-
cally if:
Ryou maneuver to avoid the obstacle.
Rthere is no longer a risk of collision.
Ran obstacle is no longer detected in front of
your vehicle.
STEER CONTROL
General information
STEER CONTROL helps you by transmitting a
noticeable steering force to the steering wheel
in the direction required for vehicle stabilization.
This steering assistance is provided in particular
if:
Rboth right wheels or both left wheels are on a
wet or slippery road surface when you brake
Rthe vehicle begins to skid
Important safety notes
iObserve the "Important safety notes" sec-
tion (Ypage 64). No steering support is provided from STEER
CONTROL, if:
RESP®is deactivated
RESP®is malfunctioning
Rthe steering is malfunctioning
If ESP®is malfunctioning, you will be assisted
further by the electrical power steering.
Protection against theft
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
XTo activate with the SmartKey: remove the
SmartKey from the ignition lock.
XTo activate with KEYLESS-GO start-func-
tion or KEYLESS-GO: switch the ignition off
and open the driver's door.
XTo deactivate: switch on the ignition.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Anyone
can start the engine if a valid SmartKey has been
left inside the vehicle.
iThe 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)
74Protection against theft
Safety

XTo arm:lock the vehicle with the SmartKey or
KEYLESS-GO.
Indicator lamp :flashes. The alarm system
is armed after approximately ten seconds.
XTo disarm: unlock the vehicle with the Smart-
Key or KEYLESS-GO.
or
XInsert the SmartKey into the ignition lock.
or
XVehicles with KEYLESS-GO start function
or KEYLESS-GO: press the Start/Stop but-
ton.
The SmartKey must be in the vehicle.
A visual and audible alarm is triggered if the
alarm system is armed and you open:
Ra door
Rthe vehicle with the mechanical key
Rthe trunk lid
Rthe hood
Rthe stowage compartment/telephone com-
partment under the armrest in vehicles with
automatic transmission
XTo stop the alarm with the SmartKey:
press the %or& button on the Smart-
Key.
The alarm is stopped.
or
XVehicles with KEYLESS-GO start-function
or KEYLESS-GO: remove the Start/Stop but-
ton from the ignition lock (
Ypage 124).
XInsert the SmartKey into the ignition lock.
The alarm is stopped.
XTo stop the alarm using KEYLESS-GO:
grasp the outside door handle. The SmartKey
must be outside the vehicle.
The alarm is stopped.
or
XPress 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 op en d
oor that triggered it, for example.
iIf 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 a message
or establishes a data connection provided
that:
Ryou have subscribed to the mbrace service.
Rthe mbrace service has been activated
properly.
Rthe necessary mobile phone network is
available.
Protection against theft75
Safety
Z

SmartKey
Important safety notes
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart 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.
GWARNING
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:
Rwith electronic devices, e.g. a mobile phone
or another SmartKey.
Rwith metallic objects, e.g. coins or metal foil.
Rinside metallic objects, e.g. a metal case.
This can affect the functionality of the Smart- Key. Vehicles with KEYLESS-GO start function:
do
not keep the SmartKey in the cargo compart-
ment. Otherwise, the SmartKey may not be
detected, e.g. when starting the engine using
the Start/Stop button.
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:
Rwhen starting the engine
Rwhile driving
Rwhen the external door handles are touched
Rduring convenience closing
SmartKey functions
:& Locks the vehicle
;FOpens the trunk lid
=%Unlocks the vehicle
XTo unlock centrally: press the%button.
If you do not open the vehicle within approx-
imately 40 seconds of unlocking:
Rthe vehicle is locked again.
Rprotection against theft is reactivated.
XTo lock centrally: press the&button.
The SmartKey centrally locks and unlocks the
following components:
Rthe doors
Rthe trunk lid
Rthe glove box
Rthe fuel filler flap
The turn signals flash once when unlocking and
three times when locking.
You can also set an audible signal to confirm
that the vehicle has been locked. The audible
signal can be activated and deactivated via the
76SmartKey
Opening and closing

multimedia system; see the Digital Operator's
Manual.
You will receive visual and acoustic locking con-
firmation if all components were able to be
locked.
When the locator lighting is activated via the
multimedia system, it lights up when it is dark
after the vehicle is unlocked with the SmartKey;
see the Digital Operator's Manual.
XTo open the trunk lid automatically from
outside the vehicle:press and hold theF
button until the trunk lid opens.
KEYLESS-GO
General notes
Bear in mind that the engine can be started by
any of the vehicle occupants if there is a Smart-
Key in the vehicle (
Ypage 125).
Locking/unlocking centrally
You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry the
SmartKey with you. You can combine the func-
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
& button on the SmartKey.
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. When locking or
unlocking with KEYLESS-GO, the distance
between the SmartKey and the corresponding
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:
Rwhen starting the engine
Rwhile driving
Rwhen the external door handles are touched
Rduring convenience closing
XTo unlock the vehicle: touch the inner sur-
face of the door handle.
XTo lock the vehicle: touch sensor surface :
or ;.
Make sure that you do not touch the inner
surface of the door handle.
XConvenience closing feature: touch
recessed sensor surface ;for an extended
period.
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.
XTo deactivate: press the&button on the
SmartKey twice in rapid succession.
The battery check lamp (
Ypage 79) of the
SmartKey flashes twice briefly and lights up
once, then KEYLESS-GO is deactivated.
XTo activate: press any button on the Smart-
Key.
or
XInsert the SmartKey into the ignition lock.
KEYLESS-GO and all of its associated features
are available again.
KEYLESS-GO start function
General notes
Bear in mind that the engine can be started by
any of the vehicle occupants if there is a Smart-
Key in the vehicle (
Ypage 125).
SmartKey77
Opening and closing
Z

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.
XTo change the setting:press and hold down
the % and& buttons simultaneously
for approximately six seconds until the bat-
tery check lamp (
Ypage 79) flashes twice.
If the setting of the locking system is changed
within the signal range of the vehicle, pressing
the & or% button:
Rlocks or
Runlocks the vehicle
The SmartKey now functions as follows:
XTo unlock: press the%button once.
XTo unlock centrally: press the%button
twice.
XTo lock: press the &button.
XTo restore the factory settings: press and
hold the %and& buttons simultane-
ously for approximately six seconds until the
battery check lamp (
Ypage 79) flashes
twice.
The KEYLESS-GO functions can be changed as
follows:
XTo unlock the driver's door: touch the inner
surface of the door handle on the driver's
door.
XTo unlock centrally: touch the inner surface
of the front-passenger door handle.
XTo lock centrally: touch the outer sensor
surface on one of the door handles.
Mechanical key
General notes
If the vehicle can no longer be locked or
unlocked with the SmartKey or KEYLESS-GO,
use the mechanical key.
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
(
Ypage 74). If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked auto-
matically.
XTo unlock the fuel filler flap:
insert the
SmartKey into the ignition lock.
Removing the mechanical key
XPush release catch :in the direction of the
arrow and at the same time remove mechan- ical key ;from the SmartKey.
Further information on locking/unlocking the
driver's door (
Ypage 83).
Inserting the mechanical key
XPush mechanical key ;completely into the
SmartKey until it engages and release
catch :is back in its basic position.
SmartKey battery
Important safety notes
GWARNING
Batteries contain toxic and corrosive substan- ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatalinjury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
HEnvironmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
78SmartKey
Opening and closing

Problems with the SmartKey
ProblemPossible causes/consequences andMSolutions
You can no longer lock or
unlock the vehicle using
the SmartKey.The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 79) and replace it if necessary
(Ypage 79).
If this does not work:
XLock or unlock the vehicle using the mechanical key (Ypage 83).
There is interference from a powerful source of radio waves.
XLock or unlock the vehicle using the mechanical key (Ypage 83).
The SmartKey is faulty.
XLock or unlock the vehicle using the mechanical key (Ypage 83).
XHave the SmartKey checked at a qualified specialist workshop.
You can no longer lock or
unlock the vehicle using
KEYLESS-GO.KEYLESS-GO was deactivated.
XReactivate KEYLESS-GO (Ypage 77).
The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 79) and replace it if necessary
(Ypage 79).
If this does not work:
XLock or unlock the vehicle using the mechanical key (Ypage 83).
There is interference from a powerful source of radio waves.
XLock or unlock the vehicle using the mechanical key (Ypage 83).
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 83).
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 303).
or
XJump-start the vehicle (Ypage 304).
or
XConsult a qualified specialist workshop.
80SmartKey
Opening and closing

ProblemPossible causes/consequences andMSolutions
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 79) and replace it if necessary
(Ypage 79).
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.
Doors
Important safety notes
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart 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
When a door is opened, the side window on that side opens slightly. When the door is closed, the
side window closes again.
!The side windows will not open/close if the
battery is discharged or if the side windows
have iced up. It will then not be possible to
close the door. Do not attempt to force the
door closed. You could otherwise damage the
door or the side window.
You can open a door from inside the vehicle
even if it has been locked. If the vehicle has been
locked with the SmartKey or with KEYLESS-GO,
opening a door from the inside will trigger the
anti-theft alarm system. Switch off the alarm
(
Ypage 74).
Doors81
Opening and closing
Z