2018 MERCEDES-BENZ C-CLASS CABRIOLET keyless

To start the vehicle without actively using the
SmartKey:
Rthe Start/Stop button must be inserted in the
ignition lock.
Rthe SmartKey must be in the vehicle.
Rthe vehicle must not be locked with the
SmartKey or KEYLESS-GO. (Ypage 77)
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.
If you lock the vehicle with the SmartKey remote control or with KEYLESS-GO, after a short time:
Ryou will not be able to switch on the ignition
with the Start/Stop button.
Ryou will no longer be able to start the engine
with the Start/Stop button until the vehicle is
unlocked again.
If you lock the vehicle centrally using the button
on the front door (
Ypage 82), you can continue
to start the engine with the Start/Stop button.
The engine can be switched off while the vehicle
is in motion by pressing and holding the Start/
Stop button for three seconds. This function
operates independently of the ECO start/stop
automatic engine switch-off function.
Key positions with the Start/Stop button
:Start/Stop button
;Ignition lock
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light
up. Warning and indicator lamps: see
(
Ypage 241). If Start/Stop button
:has not yet been
pressed, this corresponds to the SmartKey
being removed from the ignition.
XTo switch on the power supply: press
Start/Stop button :once.
The power supply is switched on. You can now activate the windshield wipers, for example.
The power supply is switched off again if:
Rthe driver's door is opened and
Ryou press Start/Stop button :twice when in
this position
XTo switch on the ignition: press Start/Stop
button :twice.
The ignition is switched on.
The ignition is switched off again if:
Ryou do not start the engine from this position within 15 minutes
Ryou press Start/Stop button :once when in
this position
The power supply is switched off again if:
Rthe driver's door is opened and
Ryou press Start/Stop button :once when in
this position
Removing the Start/Stop button
You can remove the Start/Stop button from the ignition lock and start the vehicle as normal
using the SmartKey.
It is possible to switch between Start/Stop but-
ton mode and key operation only when the
transmission is in position j.
XRemove Start/Stop button :from ignition
lock ;.
You do not have to remove the Start/Stop but-
ton from the ignition lock when you leave the
vehicle. You should, however, always take the
SmartKey with you when leaving the vehicle. As
long as the SmartKey is in the vehicle:
Rthe vehicle can be started using the Start/
Stop button
Rthe electrically powered equipment can be
operated
124Driving
Driving and parking

Starting the engine
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
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There
is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation.
GWARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or
parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
General notes
The catalytic converter is preheated for up to
30 seconds after a cold start. The sound of the
engine may change during this time.
Automatic transmission
XShift the transmission to position j
(Ypage 133).
The transmission position indicator on the
multifunction display shows j
(
Ypage 134).
iYou can start the engine in transmission
position jand i.
Starting procedure with the SmartKey
To start the engine using the SmartKey instead
of the Start/Stop button, pull the Start/Stop
button out of the ignition lock.
XTurn the SmartKey to position 3in the igni-
tion lock and release it as soon as the engine
is running.
If the engine will not start:
XRemove the SmartKey from the ignition lock.
XReinsert the SmartKey into the ignition lock
after a short waiting period.
XTurn the SmartKey to position 2in the igni-
tion lock (Ypage 123).
The indicator lamps in the instrument cluster
light up (
Ypage 241).
XTurn the SmartKey to position 3
(Ypage 123) in the ignition lock and release it
as soon as the engine is running.
Starting procedure with the Start/Stop
button
The Start/Stop button is only available on vehi-
cles with KEYLESS-GO or the KEYLESS-GO start
function.
The Start/Stop button can be used to start the
vehicle manually without inserting the SmartKey
into the ignition lock. The Start/Stop button
must be inserted in the ignition lock and the
SmartKey must be in the vehicle. This mode for
starting the engine operates independently of
the ECO start/stop automatic engine start func- tion.
You can start the engine if a valid SmartKey is in
the vehicle. Switch off the engine and always
Driving125
Driving and parking
Z

leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
XIf the transmission is in positionhork:
push the DIRECT SELECT lever up or down to
the first point of resistance.
XIf the transmission is in position j: depress
the brake pedal and push the DIRECT SELECT
lever up or down to the first point of resist-
ance.
If you switch the engine off with the transmis-
sion in position korh, the automatic trans-
mission shifts to iautomatically.
With the SmartKey: if you then open the driv-
er's door or the front-passenger door or remove the SmartKey from the ignition lock, the auto-
matic transmission shifts to jautomatically.
With the Start/Stop button: if you then open
the driver's door or the front-passenger door,
the automatic transmission shifts to jauto-
matically.
If you want the automatic transmission to
remain in neutral i, e.g. when having the vehi-
cle cleaned in an automatic, tow-through car
wash:
XVehicles with KEYLESS-GO or KEYLESS-
GO start function: remove the Start/Stop
button from the ignition lock.
XInsert the SmartKey into the ignition lock.
XAll vehicles: switch the ignition on.
XDepress the brake pedal and keep it
depressed.
XEngage neutral i.
XRelease the brake pedal.
XRelease the electric parking brake.
XSwitch off the ignition and leave the SmartKey
in the ignition lock.
Engaging the drive position
XIf the transmission is in position kori:
push the DIRECT SELECT lever down past the first point of resistance.
XIf the transmission is in position j: depress
the brake pedal and push the DIRECT SELECT lever down past the first point of resistance.
Transmission position and drive pro-
gram display
The current transmission position and drive pro-
gram appear in the multifunction display.
:Status symbol drive program
;Transmission position
=Gear
The arrows in the transmission position display
show how and into which transmission positions
you can shift using the DIRECT SELECT lever.
If the transmission position display in the mul-
tifunction display is not working, you should pull
away carefully to check whether the desired
transmission position is engaged. Ideally, you
should select transmission position hand
drive program E(for Mercedes-AMG vehicles:
drive program C) orS.
134Automatic transmission
Driving and parking

GWARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make sure that fuel does not come into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children.
If you or others come into contact with fuel,
observe the following:
RWash away fuel from skin immediately
using soap and water.
RIf fuel comes into contact with your eyes,
immediately rinse them thoroughly with
clean water. Seek medical assistance with-
out delay.
RIf fuel is swallowed, seek medical assis-
tance without delay. Do not induce vomit-
ing.
RImmediately change out of clothing which
has come into contact with fuel.
GWARNING
Electrostatic buildup can create sparks and
ignite fuel vapors. There is a risk of fire and
explosion.
Always touch the vehicle body before opening
the fuel filler flap or touching the fuel pump
nozzle. Any existing electrostatic buildup is
thereby discharged.
Do not get into the vehicle again during the refu-
eling process. otherwise electrostatic charge
could build up again.
!Do not use diesel to refuel vehicles with a
gasoline engine. Do not switch on the ignition
if you accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel system. Even small amounts of the wrong fuel could
result in damage to the fuel system and the
engine. Notify a qualified specialist workshop
and have the fuel tank and fuel lines drained
completely.
!Overfilling the fuel tank could damage the
fuel system.
!Take care not to spill any fuel on painted
surfaces. You could otherwise damage the
paintwork.
!Use a filter when adding fuel from a fuel can.
The fuel lines and/or the fuel injection system
could otherwise be blocked by particles from
the fuel can.
If you overfill the fuel tank, fuel could spray out
when the fuel pump nozzle is removed.
For further information on fuel and fuel quality
(
Ypage 340).
Refueling
General information
Pay attention to the important safety notes
(Ypage 141).
If you unlock/lock the vehicle from the outside,
the fuel filler flap also unlocks/locks.
The position of the 8fuel filler cap is dis-
played on the instrument cluster. The arrow next
to the filling pump indicates the side of the vehi-
cle.
Opening the fuel filler flap
:To open the fuel filler flap
;To insert the fuel filler cap
=Tire pressure table
?Instruction label for fuel type to be refueled
XSwitch off the engine.
XRemove the SmartKey from the ignition lock.
or, in vehicles with KEYLESS-GO start-function
or KEYLESS ‑GO
XOpen the driver's door.
The vehicle electronics are now in setting u.
This is the same as "SmartKey removed".
XPress the fuel filler flap in the direction of
arrow :.
The fuel filler flap swings up.
142Refueling
Driving and parking

XTurn the fuel filler cap counterclockwise and
remove it.
XInsert the fuel filler cap into the holder on theinside of fuel filler flap ;.
XCompletely insert the filler neck of the fuel
pump nozzle into the tank, hook in place and
refuel.
XOnly fill the tank until the pump nozzle
switches off.
Do not add any more fuel after the pump stops
filling for the first time. Otherwise, fuel may leak
out.
Closing the fuel filler flap
XReplace the cap on the filler neck and turn
clockwise until it engages audibly.
XClose the fuel filler flap.
Close the fuel filler flap before locking the vehi-
cle.
If you are driving with the fuel filler cap open, the
8 reserve fuel warning lamp flashes. A mes-
sage appears in the multifunction display
(
Ypage 227).
Problems with fuel and the fuel tank
ProblemPossible causes/consequences and MSolutions
Fuel is leaking from the
vehicle.GWARNING
The fuel line or the fuel tank is faulty.
Risk of explosion or fire.
XApply the electric parking brake.
XSwitch off the engine.
XRemove the SmartKey from the ignition lock.
or, in vehicles with KEYLESS-GO start-function or KEYLESS ‑GO
XOpen the driver's door.
The vehicle electronics are now in positionu. This is the same as
the key having been removed.
XDo not restart the engine under any circumstances.
XConsult a qualified specialist workshop.
The fuel filler flap cannot
be opened.The fuel filler flap is not unlocked.
XUnlock the vehicle (Ypage 76).
The SmartKey battery is discharged or nearly discharged.
XUnlock the vehicle using the mechanical key (Ypage 78).
The fuel filler flap is unlocked, but the opening mechanism is jammed.
XConsult a qualified specialist workshop.
Parking
Important safety notes
GWARNING
Flammable material such as leaves, grass or
twigs may ignite if they come into contact with
hot parts of the exhaust system or exhaust
gas flow. There is a risk of fire.
Park the vehicle so that no flammable mate-
rials come into contact with parts of the vehi-
cle which are hot. Take particular care not to
park on dry grassland or harvested grain
fields.
Parking143
Driving and parking
Z

GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking position P.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle.
!Always secure the vehicle correctly against
rolling away. Otherwise, the vehicle or its driv-
etrain could be damaged.
To ensure that the vehicle is secured against
rolling away unintentionally:
Rthe electric parking brake must be applied.
Rthe transmission must be in position jand
the SmartKey must be removed from the igni-
tion lock.
Rthe front wheels must be turned towards the
curb on steep uphill or downhill gradients.
Rthe empty vehicle must be secured at the
front axle with a wheel chock or similar, for
example, on uphill or downhill gradients.
Ron uphill or downhill gradients the laden vehi- cle must also be secured at the rear axle, for
example with a wheel chock or similar object.
Switching off the engine
Important safety notes
GWARNING
The automatic transmission switches to neu-
tral position Nwhen you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
After switching off the engine, always switch
to parking position P. Prevent the parked vehi-
cle from rolling away by applying the parking
brake.
Vehicles with automatic transmission
XApply the electric parking brake.
XShift the transmission to position j.
XWith the SmartKey:turn the SmartKey to
position uin the ignition lock and remove it.
The immobilizer is activated.
XWith the Start/Stop button: press the
Start/Stop button (Ypage 124).
The engine stops and all the indicator lamps in
the instrument cluster go out.
When the driver's door is closed, this corre-
sponds to key position 1. When the driver's
door is open, this corresponds to key position
u, "Key removed".
If you switch the engine off with the transmis-
sion in position korh the automatic trans-
mission shifts to iautomatically.
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 jautomatically.
With the Start/Stop button: if you then open
the driver's door or the front-passenger door,
the automatic transmission shifts to jauto-
matically.
If you want the automatic transmission to
remain in neutral i, for example, when having
the vehicle cleaned in an automatic car wash
with a towing system:
XVehicles with KEYLESS-GO or KEYLESS-
GO start function: remove the Start/Stop
button from the ignition lock.
XInsert the SmartKey into the ignition lock.
XAll vehicles: switch the ignition on.
XDepress the brake pedal and keep it
depressed.
XEngage neutral i.
XRelease the brake pedal.
XRelease the electric parking brake.
XSwitch off the ignition and leave the SmartKey
in the ignition lock.
The engine can be switched off in an emergency
while the vehicle is in motion by pressing and
holding the Start/Stop button for three sec-
onds. This function operates independently of
the ECO start/stop automatic engine switch-off function.
144Parking
Driving and parking

Additional service products
Import ant safety notes
GWARNIN G
Certain component sin th eengin ecompart-
ment, suc has th eengine, radiato rand part s
of th eexhaust system, can become ver yhot .
Working in th eengin ecompartmen tposes a
ris kof injury.
Wher epossible, let th eengin ecool down and
touch only th ecomponent sdescribed in th e
following.
GWARNIN G
The engin ecompartmen tcontain smoving
components. Certain components, suc has
th eradiato rfan ,may continu eto run or start
again suddenly when th eignition is off .There
is aris kof injury.
If you need to do any wor kinside th eengin e
compartment:
Rswitch off th eignition
Rnever reac hint oth earea wher ethere is a
ris kof danger from moving components,
suc has th efan rotation area
Rremove jewelr yand watches
Rkeep items of clothing and hair ,for exam-
ple, away from moving part s
GWARNING
The coolin gsystem is pressurized, particularly
when th emotor is warm .If you open th ecap ,
you could be scalded if hot coolan tsprays out .
There is aris kof injury.
Let th eengin ecool down before you open th e
cap .Wear gloves and eye protection .Slowly
open th ecap to reliev epressure.
GWARNIN G
Opening th ehoo dwhen th eengin eis over-
heated or when there is afir ein th eengin e
compartmen tcould expos eyou to hot gase s
or other servic eproducts .There is aris kof
injury.
Let an overheate dengin ecool down before
opening th ehood. If there is afir ein th e
engin ecompartment, keep th ehoo dclosed
and contact th efir edepartment.
Checking coolant level
Checking th ecoolan tlevel (example)
XPark th evehicl eon alevel surface.
Only chec kth ecoolan tlevel when th evehicl e
is on alevel surfac eand th eengin ehas cooled
down .
XTurn th eSmartKey to position 2in th eigni-
tion loc k (Ypage 123).
or
XPress th eStart/Sto pbutto ntwice on vehicles
wit hKEYLESS-GO or th eKEYLESS-GO start
function (
Ypage 124).
XCheckth ecoolan ttemperature display in th e
instrumen tcluste r (Ypage 36).
The coolan ttemperature mus tbe belo w
15 8 ‡ (70 †).
XTurn th eSmartKey to position gin th eigni-
tion loc k (Ypage 123).
or
XPress th eStart/Sto pbutto nonce on vehicles
wit hKEYLESS-GO or th eKEYLESS-GO start
function (
Ypage 124).
XSlowly tur ncap :half atur ncounter-clock -
wise and allow excess pressur eto escape.
XTurn cap :further counter-clockwise and
remove it .
If th ecoolan tis at th elevel of marke rbar =
in th efiller neck when cold, there is enough
coolan tin coolan texpansion tan k;.
If th ecoolan tlevel is approximately 0. 6in
(1. 5cm) abov emarke rbar =in th efiller neck
when warm ,there is enough coolan tin expan -
sion tan k;.
284Engine compartment
Maintenance and care

XApply the electric parking brake manually.
XTurn the SmartKey to position2in the igni-
tion lock (Ypage 123).
or
XPress the Start/Stop button twice on vehicles
with KEYLESS-GO or the KEYLESS-GO start
function (
Ypage 124).
XPress AIRCAP button :.
The wind deflector between the windshield
and the soft top is extended.
XClean net ;of the wind deflector with a soft
brush or a moist cloth.
If there is a large amount of dirt on the net:
Rclean with the care products and cleaning
agents recommended and approved by
Mercedes-Benz
Rrinse with clean water
Cleaning the AIRCAP wind screen
Clean the AIRCAP wind screen with the soft top
open.
XApply the electric parking brake manually.
XTurn the SmartKey to position 2in the igni-
tion lock (Ypage 123).
or
XPress the Start/Stop button twice on vehicles
with KEYLESS-GO or the KEYLESS-GO start
function (
Ypage 124).
XOpen the soft top (Ypage 89).
XPress AIRCAP button :.
The AIRCAP wind screen moves up.
XClean net ;of the AIRCAP wind screen with
a damp cloth. Use only the care products and cleaning agents recommended and approved
by Mercedes-Benz for this.
Cleaning the folding wind screen
!Do not use high-pressure cleaning equip-
ment to clean the net.
The folding wind screen is stowed in a bag. The
bag is secured with a securing strap to the
through-loading facility behind the rear seat.
Observe the information on the correct installa- tion of the folding wind screen (
Ypage 92).
XClean the net of the folding wind screen witha damp cloth together with the care products
290Care
Maintenance and care