engine MERCEDES-BENZ C-CLASS CABRIOLET 2021 Owner's Guide

#
Ifth ege arshift recommendation 1appea rs
next tothe transmission position displa y,
shift tothere commended gear. Using kickd
own #
Maximum acceleration: depressthe accel‐
erator pedal be yond the pressure point.
To protect against engine overrev ,th e automatic
transmission shifts up tothe next gear when
maximum engine speed has been reached. Glide mode function
*
NO
TEMercedes-AMG vehicles #
Obser vethe no tes in the Supplement.
Yo u could otherwise failto recognise
dangers. Wi
th an anticipatory driving style, Glide mode
helps youto reduce fuel consum ption.
Glide mode is characterised bythefo llowing:
R The combustion engine is disconnected from
th e driv etra in and continues torun in neutral.
R The transmission position displ ayh is
shown in green.
R Vehicles with 48 V on-board electrical
sy stem (EQ-Boost technology): The com‐
bustion engine can be switched off. All of the
ve hicle functions remain active.
Glide mode is activated if thefo llowing condi‐
tions are me t:
R Drive prog ram ; is selected.
R The speed is within a suita blerange. R
The road's course is suitable, e.g. no steep
uphill or downhill inclines or tight bends.
R There is no trailer hitched up tothe trailer
hitch, and no bicycle rack Fitted.
R You do not depress the accelera tor or brake
pedal (e xcept for light brake applications).
% Glide mode can also be activated if you ha ve
selected the "Eco" setting forth e drive in the
drive prog ram =.
Glide mode is deactivated again if one of the
conditions is no longer met.
Glide mode can also be pr evented bythefo llow‐
ing parame ters:
R Incline
R Downhill gradient
R Temp erature
R Height
R Speed
R Operating status of the engine
R Traf fic situation 15 4
Driving and pa rking

#
Toavo id creating ano ther electros tatic
ch arge , do not getinto theve hicle again
during there fuelling process. &
WARNING Risk offire from fuel mixture
Ve hicles with a diesel engine:
If yo u mix diesel fuel with petrol, theflash
point of the fuel mixture is lo werth an that of
pure diesel fuel.
While the engine is running, component
pa rts in theex haust sy stem may overheat
without warning. #
Neverre fuel using petrol. #
Never mix petrol with diesel fuel. *
NO
TEDama gecaused bythe wrong fuel Ve
hicles with a petrol engine:
Even small amounts of the wrong fuel could
re sult in damage tothe fuel sy stem, the
engine and the emission control sy stem. #
Only refuel using unleaded, sulphu r-free
petrol that con form sto European
EN 228, or an equi valent specification.
Fu el of this specification may con tain up to
10 %ethanol. Your vehicle is suitable for use
with E10 fuel.
Ne verre fuel with one of thefo llowing fuels:
R diesel
R regular petrol with an octane number
lo we rth an 91 RON
R petrol with more than 10%ethanol byvol‐
ume, e.g. E15, E20, E85, E100
R petrol with more than 3% me thanol by
vo lume, e.g. M15, M30
R petrol with additives con taining me tal
If yo u ha veacciden tally refuelled with the
wrong fuel: #
do not swit ch the ignition on. #
Consult a qualified specialist workshop. *
NO
TEDama gecaused bythe wrong fuel Ve
hicles with a diesel engine:
Even small amounts of the wrong fuel could
re sult in damage tothe fuel sy stem, the
engine and the emission control sy stem. #
Only refuel using sulphu r-free diesel
fuel that con form sto European stand‐
ard EN 590, or an equivalent specifica‐
tion.
In countries without sulphur-f ree diesel
fuel, refuel using only lo w-sulphur diesel
fuel with a sulphur content less than
50 ppm. #
Vehicles without diesel particulate
fi lter: refuel using only diesel fuel with
a sulphur content less than 500 ppm.
Ne verre fuel using any of thefo llowing fuels:
R petrol
R marine diesel
R heating oil
R pure bio-diesel fuel or vege table oil 15 6
Driving and pa rking

R
paraf fin or kerosene
If yo u acciden tally refuel with the wrong fuel: #
Do not switch the ignition on. #
Consult a qualified specialist workshop. *
NO
TEDo not use diesel torefuel vehi‐
cles with a petrol engine If
yo u ha veacciden tally refuelled with the
wrong fuel:
R do not swit chthe ignition on. Otherwise
fuel can enter the engine.
Even small amounts of the wrong fuel
could result in damage tothe fuel sy stem
and the engine. The repair costs are high. #
Consult a qualified specialist workshop. #
Have the fuel tank and fuel lines
drained compl etely. *
NO
TEDo not use petrol torefuel vehi‐
cles with a diesel engine If
yo u ha veacciden tally refuelled with the
wrong fuel:
R do not swit chthe ignition on. Otherwise,
fuel can enter the fuel sy stem.
Even small amounts of the wrong fuel
could result in damage tothe fuel sy stem
and the engine. The repair costs are high. #
Consult a qualified specialist workshop. #
Have the fuel tank and fuel lines
drained compl etely. *
NO
TEDama getothe fuel sy stem caused
by ove rfilled fuel tanks #
Only fill th e fuel tank until the pump
nozzle switches off. *
NO
TEFuel may spr ayout when you
re mo vethe fuel pump nozzle #
Only fill th e fuel tank until the pump
nozzle switches off. Re
quirements:
R The vehicle is unloc ked.
% Do not get into theve hicle again during the
re fuelling process. Otherwise, electros tatic
ch arge could build up again.
Obser vethe no tes on operating fluids and fuel.
The recommended octane number foryo ur vehi‐
cle can be found on the information label in the
fuel filler flap. Driving and parking
157

1
Fuelfiller flap
2 Brac ketfo r fuel filler cap
3 Tyre pressure table
4 QR code forre scue card
5 Stationary heater indication
6 Fuel type #
Press on the back area of fuel filler flap 1. #
Turn the fuel filler cap anti-clockwise and
re mo veit. #
Insert fuel filler cap from abo veinto brac ket
2 . #
Comple tely inse rtthe pump nozzle into the
ta nk filler nec k,hook in place and refuel. #
Only fill th e fuel tank until the pump nozzle
switches off.
% Vehicles with a diesel engine: theta nk
fi ller neck is designed forre fuelling at diesel
fi lling pumps.
% Vehicles with a diesel engine: whenthe
fuel tank is compl etely em pty, top up with at
least 5 litres of diesel.
% Vehicles with a diesel engine: use afiller
neck with a lar gediame terfo rve hicles with
a diesel engine when topping up fuel from a
fuel can. Otherwise, thefiller neck cannot
slide into theta nk. #
Replace the cap on thefiller neck and turn
clockwise until it engages audibl y. #
Close fuel filler flap 1. Ad
Blue ®
(vehicles with a diesel engine on ly) Note
s onrefilling AdBlue ®
Ad Blue ®
is a wate r-soluble fluid forth e NOx
ex haust gas af tertre atment of diesel engines. In
order forth eex haust gas af tertre atment tofunc‐
tion proper ly, only use AdBlue ®
in acco rdance
with ISO 22 241.
Ad Blue ®
is ch aracterised bythefo llowing:
R non-t oxic
R colourless and odourless
R non-flammable
If yo u open theAd Blue ®
tank, small amounts of
ammonia vapour may be released. Only fill the
Ad Blue ®
tank in well-ventilated areas.
Do not let AdBlue ®
come into contact wi thskin,
ey es or clo thes. Keep AdBlue ®
aw ay from chil‐
dren.
Do not ingest AdBlue ®
. If AdBlue ®
is swallo wed,
immediately rinse your mouth out thoroughly.
Drink plenty of water.Seek medical attention at
once. 15 8
Driving and pa rking

Obser
vethe no tes on operating fluids
(/ page 416).
Ad Blue ®
is available here:
R AdBlue ®
can be topped up byfast service at
a qu alified specialist workshop, e.g. a
Mercedes-Benz Service Centre.
R AdBlue ®
is available at many filling stations
from AdBlue ®
filling pumps.
R Alternativel y,Ad Blue ®
is available at qualified
specialist workshops, e.g. Mercedes-Benz
Service Centres, and at many filling stations
in Ad Blue ®
re fill canis ters or AdBlue ®
re fill
bottles.
% Ensure the connection between there fill
con tainer and vehicle filler neck does not
drip. To
pping up AdBlue ®
* NOTEEngine dama gedue toAd Blue ®
being in the fuel #
AdBlue ®
must not be used tofill the
fuel tank. #
Only use AdBlue ®
to fill th eAd Blue ®
ta nk. #
Do not overfill theAd Blue ®
tank. *
NO
TEContamination of theve hicle inte‐
ri or due toAd Blue ®
lea kage #
Afterto pping up, carefully close the
Ad Blue ®
re fill con tainer. #
Avoid car rying AdBlue ®
re fill con tainers
permanently in theve hicle. Re
quirements:
R The vehicle is unloc ked. The
following messages appear in order in the
multifunction display when theAd Blue ®
tank
requ irestopping up:
R Refill AdBlue See Owner’s Manual The
Ad Blue ®
leve l has fallen below there ser ve
ra nge. Top up AdBlue ®
immediately.
R Top up AdBlue Emergency op. in XXX miles
See Owner's ManualThe low AdBlue ®
level
will lead tolimited per form ance af terthe
re maining dis tance displ ayed has been
driven. Top up AdBlue ®
immediately.
R XX,X l Top up AdBlue Emer. op.: max. XXX
km/h Start not poss. in XXX kmThe low
AdBlue ®
leve l will lead tolimited per form‐
ance from the speed displa yed. Af terthe
re maining dis tance displ ayed has been cov‐
ered, it will no longer be possible tostart the
engine. Top up with at least the amount of
Ad Blue ®
displ ayed.
R XX,X l Top up AdBlue Switch on ignition, wait
60 sec. or eng. start not poss. TheAdBlue ®
ta nk is em pty. Yo u can no lon gerst art the
engine. Top up with at least the amount of Driving and parking
15 9

Ad
Blue ®
displ ayed. Switch on the ignition
and waitfor appro ximately 60 seconds. Start
th e engine.
Yo u can see theAd Blue ®
ra nge and le vel in the
Service menu in the multifunction displa y.
% The AdBlue ®
ra nge shown depends strongly
on the driving style and operating condi‐
tions. The actual range can therefore deviate
from the calculated range. Opening the
AdBlue ®
filler cap #
Press on the back area of fuel filler flap 1. #
Turn AdBlue ®
filler cap 2anti-clockwise and
re mo veit.
To pping up AdBlue ®
Mercedes-Benz recommends topping up
Ad Blue ®
at a filling pump. If no AdBlue ®
filling pump is
available, you can also top up AdBlue ®
using a cani ster. #
Screw onthefast ener of AdBlue ®
re fill canis‐
te r4. #
Screw disposable hose 3onto the opening
of Ad Blue ®
re fill canis ter4 until hand-tight. #
Screw disposable hose 3onto thefiller
neck of theve hicle until hand-tight. #
Lift up and tip AdBlue ®
re fill canis ter4.
The filling process stops when theAd Blue ®
ta nk is compl etely full. 16 0
Driving and pa rking

Ad
Blue ®
re fill canis ter4 can be remo ved
when it has been only partially em ptied. #
Unscr ew and close disposable hose 3and
Ad Blue ®
re fill canis ter4 inreve rse order. #
Replace AdBlue ®
filler cap 2and turn it
clockwise until it audibly engages. #
Close fuel filler flap 1. #
Swit chon the ignition for at least 60 sec‐
onds.
% Ifth e engine could not be star ted due tothe
Ad Blue ®
tan k being empty, it can take up to
60 seconds forth eto p up tobe de tected. #
Start theve hicle.
% Avoid storing AdBlue ®
re fill con tainers per‐
manently in theve hicle. Pa
rking Pa
rking theve hicle &
WARNING Risk of accident and inju ry
caused byan insuf ficiently secu redve hi‐
cle rolling away
If th eve hicle is not securely par ked suf fi‐
ciently, it can rollaw ay in an uncont rolled
wa yev en at a slight downhill gradient. #
On uphill or downhill gradients, turn the
front wheels so that theve hicle rolls
to wa rdsth eke rb if it starts moving. #
apply the parking brake. #
Switch the transmission toposition j. &
WARNING Risk offire caused byhot
ex haust sy stem parts
Flammable materials such as lea ves, grass or
twigs may ignite. #
Park theve hicle so that no flammable
material can come into con tact wi thhot
ve hicle components. #
In particular, do not park on dry grass‐
land or har vested grain fields. &
WARNING Risk of accident and inju ry
due toleaving children unat tended in the
ve hicle
If ch ildren are left unat tended in theve hicle,
th ey could, in pa rticular:
R open doors, thereby endangering other
persons or road users.
R get out and be stru ck byoncoming traf‐
fi c.
R ope rate ve hicle equipment and become
trapped, forex ample.
In addition, thech ildren could also set the
ve hicle in motion by,fo rex ample:
R releasing the parking brake.
R changing the transmission position.
R starting theve hicle. #
Never lea vechildren unat tended in the
ve hicle. Driving and parking
161

#
When leaving theve hicle, alw aysta ke
th eke y with you and lock theve hicle. #
Keep theve hicle key out of there ach of
ch ildren. *
NO
TEDama getotheve hicle due toit
ro lling away #
Alw ays secure theve hicle against roll‐
ing away. *
NO
TEDama gedue totheve hicle lo wer‐
ing Ve
hicles with AIRMATIC or le vel control:
The vehicle can lo wer because of temp era‐
ture dif fere nces or longer non-operational
times. This can cause dama getoparts of the
body. #
When stopping theve hicle and when
driving off, make sure that there are no
obs tacles su chas curbs under or in the
immediate vicinity of the body. #
Bring theve hicle toast andstill bypressing
th e brake pedal. #
On gradients, turn the front wheels so that
th eve hicle will rollto wa rdsth eke rb if it
st arts moving. #
App lythe electric parking brake. #
Enga getransmission position jin a station‐
ary vehicle with the brake pedal applied
(/ page 152). #
Switch off the engine and the ignition by
pressing the1 button. #
Release the service brake slowl y. #
Get out of theve hicle and lock it.
% When you park theve hicle, you can still
opera tethe side windo wsand the soft top
fo r appro ximately four minutes if the driver's
door is closed. Garage door opener
Prog
ramming buttons for the garage door
opener &
DANG ER Risk of death caused by
ex haust gases
Combustion engines emit poisonous exhaust
ga ses such as carbon monoxide. Inhaling
th ese exhaust gases is hazardous tohealth
and leads topoisoning. 16 2
Driving and pa rking

#
Never lea vethe engine or, if present,
th e auxiliary heating running in an
enclosed space wi thout suf ficient venti‐
lation. &
WARNING Risk of inju rywhen opening
or closing a door with thega rage door
opener
When you operate or program the door with
th e integrated garage door opener, persons
in thera nge of mo vement of the door may
become trapped or be stru ck bythe door. #
Alw ays make sure that nobody is within
th era nge of mo vement of the door. Re
quirements:
R The vehicle has been par ked outside the
ga rage or outside thera nge of mo vement of
th e door.
R The engine is switched off.
R The ignition is switched on.
% The garage door opener function is alw ays
av ailable when the ignition is switched on. #
Press and hold button 1,2or3 that you
wish toprog ram.
Indicator lamp 4flashes yello w.
% It can take up to20 seconds before the indi‐
cator lamp flashes yello w. #
Release the pr eviously pressed button.
Indicator lamp 4continues toflash yello w. #
Point remo tecontrol 5from a di stance of
1 cm to8 cm towa rds button 1,2or3. #
Press and hold button 6ofremo tecontrol
5 until one of thefo llowing signals appears:
R Indicator lamp 4lights up green contin‐
uousl y.Programming is comple te.
R Indicator lamp 4flashes green. Pro‐
gramming was successful. Additionall y,
synchronisation of thero lling code with
th e door sy stem must also be car ried out. #
If indicator lamp 4does not light up or flash
green: repeat the procedure. #
Release all of the buttons.
% The remo tecontrol forth e door drive is not
included in the scope of delivery of the
ga rage door opener.
Synchronising thero lling code
Re quirements:
R The door sy stem uses a rolling code.
R The vehicle must be within range of the
ga rage door or door drive. Driving and parking
16 3

R
get out and be stru ck byoncoming traf‐
fi c.
R ope rate vehicle equipment and become
trapped, forex ample.
In addition, thech ildren could also set the
ve hicle in motion by,fo rex ample:
R releasing the parking brake.
R changing the transmission position.
R starting theve hicle. #
Never lea vechildren unat tended in the
ve hicle. #
When leaving theve hicle, alw aysta ke
th eke y with you and lock theve hicle. #
Keep theve hicle key out of there ach of
ch ildren. The electric pa
rking brake is applied if the
tr ansmission is in position j
jand one of the
fo llowing conditions is fulfilled:
R The engine is switched off. R
The seat belt tongue is not inser ted in the
seat belt buckle of the driver's seat and the
driver's door is opened.
% Toprev ent application: pull the handle of the
electric parking brake (/ page166).
In thefo llowing situations, the electric pa rk‐
ing brake is also applied:
R The HOLD function is keeping theve hicle sta‐
tionar y.
R Active Parking Assist is keeping theve hicle
st ationar y.
R Active Dis tance Assi stDISTRONIC is bringing
th eve hicle toast andstill.
R In addition, one of thefo llowing condi‐
tions mu stbe fulfilled:
- The engine is switched off.
- The seat belt tongue is not inser ted in the
seat belt buckle of the driver's seat and
th e driver's door is opened.
- There is a sy stem malfunction.
- The po wer supp lyis insuf ficient. -
The vehicle is stationary for a lengt hy
period.
When the electric parking brake is applied, the
re d! indicator lamp lights up in the instru‐
ment clus ter.
% The electric parking brake is not automati‐
cally applied if the engine is switched off by
th e ECO start/ stop function.
Fu nction of the electric pa rking brake
(releasing automatically)
The electric parking brake is released when
th efo llowing conditions are fulfilled:
R The driver's door is closed.
R The engine is running.
R The transmission is in position hork and
yo u depress the accelera tor pedal or you
shift from transmission position jtoh or
k when on le velground.
R Ifth e transmission is in position k,the boot
lid must be closed.
R The seat belt tongue is inser ted into the seat
belt buckle of the driver's seat. Driving and parking
16 5