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

Depending on
theve hicle equipment, theve hicle
has thefo llowing 12V soc kets:
R Inthestow age compartment in the front
cent reconsole
R Inthestow age compartment in the cent re
console of there ar passenger compartment Example:
12V soc ket in thestow age compartment
in the front cent reconsole #
Fold up soc ket cap 1. #
Inse rtthe plug of the device.
If yo u ha veconnected a device tothe12 V
soc ket, le ave the co ver of thestow age compart‐
ment open. Wire
lesscharging of the mobile phone and
connection with theex terior aerial Note
s on wirelessly charging the mobile
phone &
WARNING Risk of inju rydue toobjects
being stowed incor rectly
If objects in theve hicle interior are stowed
incor rectly, they can slide or be thrown
around and hit vehicle occupants. In addi‐
tion, cup holders, open stowage spaces and
mobile phone recep tacles cannot al ways
re tain all objects within.
There is a risk of injur y,particularly in the
ev ent of sudden braking or a sudden change
in direction. #
Alw aysstow objects so that they can‐
not be throw n around in su chsitua‐
tions. #
Alw ays make sure that objects do not
pr otru de from stowage spaces, luggage
nets or stowage nets. #
Close the loc kable stow age spaces
before starting a journe y. #
Alw aysstow and secure heavy, hard,
poin ted, sharp-edged, fragile or bulky
objects in the boot/load compartment. Obser
vethe no tes on loading theve hicle. &
WARNING Risk offire from placing
objects in the mobile phone stowage
compartment
Placing other objects in the mobile phone
stow age compartment could con stitute a fire
hazard. #
Apart from a mobile phone, do not
place any other objects in the mobile
phone stowage compartment, espe‐
cially those made of me tal. 11 6
Seats and stowing

#
Place the mobile phone as close tothe
centre of mat 1as possible wi th the display
fa cing up wards.
When thech arging symbol is shown in the
multimedia sy stem, the mobile phone is
being charge d.
Malfunctions during thech arging process are
shown in the media displa y.
% The mat can be remo vedby theta bfor
cleaning, e.g. using clean, lu kewa rm wate r. Fi
tting/ removing the floormats &
WARNING Risk of accident due to
objects in the driver's foot we ll
Objects in the driver's foot we ll may impede
pedal tr avel or block a depressed pedal.
This jeopardises the operating and road
saf ety of theve hicle. #
Stow all objects in theve hicle securely
so that they cannot getinto the driver's
fo ot we ll. #
Alw aysfit th efloor mats securely and
as prescribed in order toensure that
th ere is alw ays suf ficient room forthe
pedals. #
Do not use loose floor mats and do not
place floor mats on top of one ano ther. #
Tofit: slide the cor responding seat back‐
wa rds and lay thefloor mat in thefo ot we ll. #
Press studs 1onto holders 2. #
Adjust the cor responding seat. #
Toremo ve: pull thefloor mat off the holders
2. #
Remo vethefloor mat. 11 8
Seats and stowing

Ensu
rethefo llowing before starting the engine:
R the legal stipulations in the area where your
ve hicle is par ked allow engine starting via
smartphone.
R it is safe tostart and runth e engine where
yo ur vehicle is par ked.
R the fuel tank is su fficiently full.
St arting theve hicle (Remo teOnline) &
WARNING Risk of crushing or entrap‐
ment due tounin tentional starting of the
engine
Limbs could be crushed or trapped if the
engine is star ted unintentionally during
service or maintenance work. #
Alw ays secure the engine against unin‐
te ntional starting before car rying out
maintenance or repair work. Re
quirements:
R park position jis selected.
R the anti- theft alarm sy stem is not activated.
R the panic alarm is not activated. R
the hazard warning light sy stem is switched
off.
R the bonn etis closed.
R the doors are closed and loc ked.
R the windo wsand soft top are closed. #
Start theve hicle using the smartphone.
Af tereve ryengine start, the engine runs for
te n minu tes.
Yo u can car ryout a maximum of two consecu‐
tive starting attem pts. Yo u must start theve hicle
once with theke y before trying tostart the
engine again with the smartphone. you can stop
th eve hicle again at any time.
% Further information can be found in the
smartphone app.
Securing the engine against starting before
car rying out maintenance or repair work: #
switch on the hazard warning light sy stem.
or #
unlock the doors.
or #
open a side window or the soft top. Ru
nning-in no tes To
preser vethe engine during thefirs t1, 500 km:
R Drive at varying road speeds and engine
speeds.
R Do not drive at speeds greater than
14 0 km/h.
R Drive theve hicle in drive program A
or ;.
R Shift tothe next highest gear at theve ry lat‐
est when the needle reaches the last third
before there d area in there v counter.
R Do not shift down a gear manually in order to
brake.
R Avoid overstraining theve hicle, e.g. driving at
full thro ttle.
R Do not depress the accelera tor pedal past
th e pressure point (kickdown).
R Only increase the engine speed gradually and
accelera tetheve hicle tofull speed af ter
1, 500 km. 14 0
Driving and pa rking

#
After no more than five seconds, take your
left foot quickly off the brake, but keep the
accelerator pedal depressed.
The vehicle pulls away at maximum accelera‐
tion. #
Swit chon ESP ®
once the acceleration proce‐
dure is comple te.
Ending optimised acceleration #
Remo veyour foot from the accelerator pedal. #
Reactivate the ESP ®
.
% Afteryo u pull away with optimised accelera‐
tion, components of the driv etra in can
become very hot, which means that opti‐
mised acceleration values may be reached
again on lyafte r a few minutes. Note
s on driving &
WARNING Risk of accident due to
objects in the driver's foot we ll
Objects in the driver's foot we ll may impede
pedal tr avel or block a depressed pedal. This jeopardises
the operating and road
saf ety of theve hicle. #
Stow all objects in theve hicle securely
so that they cannot getinto the driver's
fo ot we ll. #
Alw aysfit th efloor mats securely and
as prescribed in order toensure that
th ere is alw ays suf ficient room forthe
pedals. #
Do not use loose floor mats and do not
place floor mats on top of one ano ther. &
WARNING Risk of accident due toincor‐
re ct foot we ar
Incor rect foot we ar includes, forex ample:
R shoes with plat form soles
R shoes with high heels
R slippers
There is a risk of an accident. #
Alw ayswe ar suitable foot we ar so that
yo u can operate the pedals safel y. &
WARNING Risk of accident if the ignition
is switched off while driving
If yo u swit choff the ignition while driving,
saf ety functions are restricted or no longer
av ailable.
This may af fect the po werst eering sy stem
and the brake forc e boosting, forex ample.
Yo u will need touse considerably more force
to steer and brake, forex ample. #
Do not swit choff the ignition while driv‐
ing. &
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. #
Never lea vethe engine or, if present,
th e auxiliary heating running in an
enclosed space wi thout suf ficient venti‐
lation. 14 2
Driving and pa rking

The inner segment will light up and
the outer
segment will fill up when thefo llowing driving
st yle is adop ted:
R 1 Moderate acceleration
R 2 Gentle deceleration and rolling
R 3 Consis tent speed
The inner segment will not light up and the outer
segment will em pty when thefo llowing driving
st yle is adop ted:
R 1 Sporty acceleration
R 2 Heavy braking
R 3 Fluctuations in speed
The ECO display will show you when you ha ve
driven economically:
R The thre e outer segments are comple tely fil‐
led simultaneousl y.
R The ECO display lights up.
The additional range achi eved as a result of your
driving style in comparison with a driver with a
ve ry sporty driving style is shown under Bonusfrom start. The
range displ ayed does not indicate
a fixe dre duction in consum ption. ECO Assist function
ECO Assist anal
yses data forth eve hicle's expec‐
te dro ute. This allo wsthe sy stem tooptimally
adjust the driving style fo rth ero ute ahead, sa ve
fuel and recuperate.
ECO Assi stis displa yed on theAssistance
menu( /page 228). 1
Event ahead
2 Distance displ ayforth eev ent ahead
3 "Foot off the accelerator" prom pt Displ
ayable route events 1
The segments of di stance display 2show the
dis tance totheeve nt ahead as follo ws:
R Afew segments light up: theeve nt ahead is
nea r.
R Many segments light up: theeve nt ahead is
fur ther aw ay.
When theve hicle nears theeve nt, ECO Assi st
will calculate the optimal speed for maximum
fuel economy and recuperati veenergy based on
th e dis tance, speed and gradient. The Foot off
the accelerator 3messa gewill appear on the
multifunction displa y.The firs t segments in front Driving and pa
rking 147

#
Release the brake pedal. #
Switch the ignition off.
% Ifyo uth en exitth eve hicle leaving theke y in
th eve hicle, the automatic transmission
re mains in neutral i.
Engaging park position P #
Obser vethe no tes on parking theve hicle
(/ page 161). #
Dep ress the brake pedal until theve hicle
comes toast andstill. #
When theve hicle is at a standstill, press but‐
to nj.
When the transmission position display
sho wsj,th e park position is engaged. If no
transmission position display jappears,
secure theve hicle topreve nt it from rolling
aw ay.
% Depending on the situation, it may take a
short time until jis engaged. Therefore,
alw ays pay attention tothe transmission
position displa y. Pa
rk position jis engaged automatically if one
of thefo llowing conditions is me t:
R You swit choff the ignition when theve hicle
is stationary and the transmission position is
h ork.
R You open the driver's door when theve hicle
is at a standstill or when driving at a very low
speed and the transmission position is hor
k.
% Tomanoeuvre with an open driver's door,
open the driver's door while at a standstill
and engage transmission position hork
again.
Engaging drive position D #
Depress the brake pedal and push the
DIRECT SELECT le ver down past thefirst
point of resis tance.
When the automatic transmission is in transmis‐
sion position h, it shiftsthege ars automati‐
call y.This depends, among other things, on the
fo llowing factors:
R The selected drive program
R The position of the accelera tor pedal R
The driving speed Problems with
the transmission The transmission has a
faulty gear shift
Po ssible cause:
R the transmission is losing oil. #
Have the transmission checked at a qualified
specialist workshop immediately.
The acceleration characteristics getwo rse,
and the transmission no longer shifts.
Po ssible cause:
R the transmission is in emer gency operation
mode: it is only possible toshift toone gear
and reve rsege ar. #
Stop theve hicle in accordance with the traf‐
fi c conditions. #
Shift the transmission toposition j. #
Switch off the engine. #
Wait at least ten seconds. #
Tryto start the engine again. 15 2
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

When
the electric parking brake is released, the
re d! indicator lamp in the instrument clus‐
te r goes out.
Applying/releasing the electric pa rking
brake manually
Applying #
Push handle 1.
The red! indicator lamp lights up in the
instrument clus ter.
% The electric parking brake is only securely
applied if the indicator lamp is lit continu‐
ously.
Re leasing #
Swit chon the ignition. #
Pull handle 1.
The red! indicator lamp in the instru‐
ment clus ter goes out.
Emer gency braking #
Press and hold handle 1.
As long as theve hicle is driving, theRelease
parking brake message is displa yed and the
re d! indicator lamp flashes.
When theve hicle has been braked to a
st andstill, the electric parking brake is
applied. The red! indicator lamp lights
up in the instrument clus ter. Information on collision de
tection on a
pa rked vehicle If a collision is de
tected when theto w- aw ay pro‐
te ction is primed on a loc kedve hicle, you will
re cei vea notification in the multimedia sy stem
when you swit chon the ignition.
Yo u will recei veinformation about thefo llowing
points:
R The area of theve hicle that may ha vebeen
damaged.
R The forc e of the impact.
The following situations can lead toinadver tent
acti vation:
R The pa rked vehicle is mo ved, e.g. in a two-
st or ey garage.
% Deactivate tow- aw ay protection in order to
pr eve nt inadver tent acti vation. If you deacti‐
va te tow- aw ay protection, collision de tection
will also be deactivated. 16 6
Driving and pa rking

R
ESP ®
is malfunctioning.
R The steering is malfunctioning.
If ESP ®
is malfunctioning, you will be assis ted
fur ther by the electric po werst eering. HOLD function
HOLD function
The HOLD function holds
theve hicle at a stand‐
st ill without requ iring youto depress the brake
pedal, e.g. while waiting in traf fic.
The HOLD function is only an aid. The responsi‐
bility forth eve hicle safely standing still remains
with the driver.
Sy stem limits
The HOLD function is only intended toprov ide
assis tance when driving and is not a su fficient
means of safeguarding theve hicle against rolling
aw ay when stationar y.
R The incline must not be greater than 30%. Ac
tivating/deactivating the HOLD function &
WARNING Risk of an accident due tothe
HOLD function being active when you
lea vetheve hicle
If th eve hicle is only braked with the HOLD
function it could, in thefo llowing situations,
ro llaw ay:
R Ifth ere is a malfunction in the sy stem or
in the po wer supp ly.
R Ifth e HOLD function is deactivated by
depressing the accelera tor pedal or brake
pedal, e.g. byave hicle occupant. #
Alw ays secure theve hicle against roll‐
ing away before you lea veit. Re
quirements:
R The vehicle is stationar y.
R The driver's door is closed or the seat belt on
th e driver's side is fastened.
R The engine is running or has been au tomati‐
cally switched off bythe ECO start/ stop
function. R
The electric parking brake is released.
R Active Dis tance Assi stDISTRONIC is deacti‐
va ted.
R The transmission is in position h,kori.
Ac tivating the HOLD function #
Dep ress the brake pedal, and af ter a short
time quickly depress fur ther until theë
display appears in the multifunction displa y. #
Release the brake pedal.
Deactivating the HOLD function #
Depress the accelerator pedal topull away.
or #
Depress the brake pedal until theë dis‐
play disappears from the multifunction dis‐
pla y.
The HOLD function is deactivated in thefo llow‐
ing situations:
R Active Dis tance Assi stDISTRONIC is acti va‐
te d.
R The transmission is shif tedto position j. Driving and parking
17 3