2021 MERCEDES-BENZ C-CLASS CABRIOLET Owners Manual

All
vehicles
+ ENVIRONMENTAL
NOTEEnvironmental
dama gedue toimproper disposal of bat‐
te ries Batteries conta
in pollutants. It is
illegal todispose of them with the household
ru bbish. #
Dispose of batteries in an
environmen tally responsible manner.
Ta ke dischar ged batteries toaqu alified
specialist workshop or toa collection
point for used batteries. If
yo u ha vetodisconnect the12 V batter y,con‐
ta ct a qualified specialist workshop.
Comply with saf ety no tes and take protective
measures when handling batteries. Risk of
explosion. Fire, naked
flames and smoking are
prohibi ted when handling the batter y.
Av oid creating spar ks. Electrolyte
or battery acid is cor ro‐
sive. Avoid contact with the skin, eyes
or clo thing. Wear suitable pr otective
clo thing, in particular glove s, an
apron and a face mas k.Immedia tely
ri nse electrolyte or acid splashes off
with clean water.Consult a doc tor if
necessar y. We
ar saf etygl asses. Ke
ep children away. Obser
vethis Owner's Manual.
Obser vethefo llowing if you do not intend touse
th eve hicle over an extended pe riod of time:
R Activate standby mode.
R Alternatively: connect the battery toa bat‐
te ry charge r appro vedby Mercedes-Benz or
consult a qualified specialist workshop to
disconnect the batter y. Note
s onstarting assi stance and charging
th e12 V battery Ve
hicles with a lithium-ion battery
When charging the battery and during starting
assis tance, al ways use the jump-s tart connec‐
tion point in the engine compartment. 382
Breakdown assis tance

*
NO
TEDama getothe battery from over‐
vo ltage When
charging using a bat tery charge r with‐
out a restriction of the maximum charging
vo ltage, the battery or the on-board electron‐
ics can be damaged. #
Only use battery charge rs with a maxi‐
mum charging voltage of 14.8 V. All
other vehicles
When charging the battery and during starting
assis tance, al ways use the jump-s tart connec‐
tion point in the engine compartment.
* NO
TEDama getothe battery from over‐
vo ltage When
charging using a bat tery charge r with‐
out a restriction of the maximum charging
vo ltage, the battery or the on-board electron‐
ics can be damaged. #
Only use battery charge rs with a maxi‐
mum charging voltage of 14.8 V. &
WARNING Risk ofexplosion from hydro‐
ge nga s igniting
There is a danger of hydrogen gas igniting
when charging the battery if there is a short
circuit or spar ksstart toform. #
Make sure that the positive term inal of
th e connected battery does not come
into conta ct withvehicle parts. #
Never place me tal objects or tools on a
batter y. #
The described order of the battery
clamps must be obser ved when con‐
necting and disconnecting the batter y. #
When giving starting assis tance, al ways
make sure that you on lyconnect bat‐
te ry term inals with identical polarity. #
During starting assis tance, you must
obse rveth e described order for con‐
necting and disconnecting the jump
lead. #
Do not connect or disconnect the bat‐
te ry cla mp s while the engine is running. &
WARNING Risk ofexplosion during
ch arging process and starting assis tance
During thech arging process and starting
assis tance, the battery may release an explo‐
sive gas mixture. #
Avoid fire , naked flames, creating
spar ksand smoking. #
Make sure there is suf ficient ventila‐
tion. #
Do not lean over a batter y. &
WARNING Risk ofexplosion from a fro‐
zen battery
A dischar ged battery may freeze at temp era‐
tures slightly abo veor below freezing point.
During starting assis tance or battery charg‐
ing, bat tery gas can be released. #
Alw ays allow a battery tothaw before
ch arging it or per form ing starting assis‐
ta nce. Breakdown assi
stance 383

If
th e indicator/warning lamps in the instrument
clus ter do not light up at low temp eratures, it is
ve ry likely that the dischar ged battery has fro‐
zen. In this case you may neither jump-s tart the
ve hicle nor charge the batter y.
The service life of a battery that has been
th awe d may be dramatically shor tened. The
st arting characteristics may be impaired, espe‐
cially at low temp eratures.
It is recommended that you ha veathaw ed bat‐
te ry checked at a qualified specialist workshop.
All vehicles
* NO
TEDama gecaused bynumerous or
ex tended attem ptsto start the engine Nume
rous or extended attem ptsto start the
engine may damage the catalytic con verter
due tonon-combu sted fuel. #
Avoid numerous and extended attem pts
to start the engine. Obser
vethefo llowing points during starting
assis tance and when charging the battery:
R Only use undamaged jump lead/charging
cables with a suf ficient cross-section and
insula tedte rm inal clamps.
R Non- insulated parts of thete rm inal clamps
must not come into con tact wi thother me tal
parts while the jump lead/charging cable is
connected tothe battery/jump-s tart connec‐
tion point.
R The jump lead/charging cable must not
come into contact wi thany parts which may
mo vewhen the engine is running.
R Alw ays make sure that nei ther you nor the
battery is elect rostatically charge d.
R Keep away from fire and naked flames.
R Do not lean overth e batter y.
Obser vethe additional following points when
ch arging the battery:
R Only use battery charge rs tested and
appr oved for Mercedes-Benz.
R Read the battery charge r's operating instruc‐
tions before charging the batter y. Obser
vethe additional following points during
st arting assis tance:
R Starting assis tance may only be pr ovided
using vehicles, batteries or other jump start
devices with a nominal voltage of 12V.
R The vehicles must not touch.
R Vehicles with a petrol engine: jump-start
th eve hicle only when the engine and exhaust
sy stem are cold. St
arting assi stance and charging the12 V
battery Preparing
starting assi stance/charging #
Secure theve hicle byapplying the electric
parking brake. #
Automatic transmission: shiftthe trans‐
mission toposition j. #
Manual transmission: shiftthe transmis‐
sion toneutral. #
Switch off the ignition and all electrical con‐
sumers. #
Open the bonn et. 384
Breakdown assis tance

#
Fold co ver1 up in the direction of the
ar row. #
Slide co ver2 of positive clamp 3onthe
jump-s tarting connection point in the direc‐
tion of the ar row.
St arting assi stance #
Connect positive contact 3onyour vehicle
to the positive term inal of the donor battery
using the jump lead. Alw ays begin with posi‐
tive clamp 3onyour ow nve hicle firs t. #
Start the engine of the donor vehicle and run
it at idling speed. #
Connect the negative term inal of the donor
battery toear thpoint 4ofyour vehicle
using the jump lead. Begin with the donor
battery firs t. #
Start the engine of your ow nve hicle. #
Let the engines runfo r se veral minutes. #
Before disconnecting the jump leads, switch
on an electrical consumer in your ow nve hi‐
cle, e.g. there ar wind owheater or the light‐
ing.
When thest arting assis tance procedu reis com‐
ple te: #
First,re mo vethe jump leads from ear thpoint
4 and the negative term inal of the donor
batter y,then from positive conta ct3 and
th e positive term inal of the donor batter y.
Begin ea chtime wi th the conta cts onyour
ow nve hicle firs t. #
Afterre moving the jump leads, close co ver
2 of positive contact 3. #
Close co ver1. Breakdown assi
stance 385

Fu
rther information can be obtained at a quali‐
fi ed specialist workshop.
Charging #
Connect positive contact 3oftheve hicle to
th e positive term inal of thech arge r using the
ch arging cable. Alw ays begin with positive
contact 3oftheve hicle. #
Connect the negative term inal of thech arger
and ear thpoint 4ontheve hicle with the
ch arging cable. Start with thech arge r. #
Start thech arging process.
When thech arging process is comple te:#
First,re mo vethech arging cable from ear th
point 4and the negative term inal of the
ch arge r,th en from positive conta ct3 and
th e positive term inal of thech arge r.Begin
ea ch time wi th the conta cts oftheve hicle. #
Afterre moving thech arging cable, close
co ver2 of positive contact 3.#
Close co ver1.
Fu rther information can be obtained at a quali‐
fi ed specialist workshop. Re
placing the 12V battery #
Obser vethe no tes on the12 V battery
(/ page 381).
Mercedes-Benz recommends that you ha vethe
12 V battery replaced at a qualified specialist
wo rkshop, e.g. at a Mercedes-Benz Service
Centre.
Obser vethefo llowing no tes if youwa ntto
re place the battery yourself:
R Alw aysre place a faulty bat tery with a battery
which meets the specific vehicle require‐
ments.
The vehicle is equipped with an AGMtech nol‐
ogy battery (Absorbent Glass Mat) or a li th‐
ium-ion batter y.Fu llve hicle functionality is
only guaranteed with an AGM battery or lith‐
ium-ion batter y.Fo r saf etyre asons,
Mercedes-Benz recommends that you on ly
use bat teries which ha vebeen tested and
appr ovedfo ryo ur vehicle byMercedes-Benz.
R Carryove r de tach able parts, such as vent
hoses, elbow fittings or term inal co vers from
th e battery being replaced. R
Make sure that theve nt hose is al ways con‐
nected tothe original opening on the side of
th e batter y.
Fit any existing or supplied cell caps.
Otherwise, gases or battery acid could
escape.
R Make sure that de tach able parts are recon‐
nected in the same way. To
w- starting or towing away Pe
rm itted towing me thods *
NO
TEDama gefrom auto matic braking If one of
thefo llowing functions is switched
on, theve hicle brakes automatically in cer‐
ta in situations:
R Active Brake Assi st
R Active Dis tance Assi stDISTRONIC
R HOLD function
R Active Parking Assist 386
Breakdown assis tance

To
avo id damage totheve hicle, deactivate
th ese sy stems in thefo llowing or similar sit‐
uations: #
During towing #
In a car wash Mercedes-Benz
recommends transporting your
ve hicle in the case of a breakdown, rath er than
to wing it away.
Fo rto wing, use a tow rope or tow bar with bo th
axles on the ground. Do not use tow bar sys‐
te ms.
* NO
TEDama getotheve hicle due to tow‐
ing away incor rectly #
Obser vethe instructions and no tes on
to wing away. Ve
hicles with manual transmission Pe
rm itted towing me thods
Bo th axles on
th e ground Ye
s, maximum 50 km at
50 km/h
Fr ont axle
ra ised Ye
s, maximum 50 km at
50 km/h
Re ar axle
ra ised Ye
s, maximum 50 km at
50 km/h Ve
hicles with automatic transmission Pe
rm itted towing me thods
Bo th axles on
th e ground Ye
s, maximum 50 km at
50 km/h
Fr ont axle
ra ised No
Re ar axle
ra ised Ye
s, if thesteering wheel is
fi xe d in the cent reposition
with a steering wheel lock 4MATIC
vehicles Pe
rm itted towing me thods
Bo th axles on
th e ground Ye
s, maximum 50 km at
50 km/h
Fr ont axle
ra ised No
Re ar axle
ra ised No To
wing with a raised axle: towing should be
per form ed byato wing compan y. To
wing theve hicle with bo thaxles on the
gr ound #
Obser vethe no tes on the permitted towing
me thods (/ page 386). #
Make sure that the battery is connected and
ch arge d.
Obser vethefo llowing points when the battery is
dischar ged:
R the engine cann otbe star ted Breakdown assis
tance 387

R
the electric parking brake cann otbe released
or applied
R vehicles with automatic transmission: the
automatic transmission cannot be shif tedto
position iorj
% Vehicles with automatic transmission: if
th e automatic transmission cann otbe shif‐
te dto position i, orthe multifunction dis‐
play in the instrument clus ter does not show
anything, ha vetheve hicle transpor tedaw ay
( / page 389). A towing vehicle with lifting
equipment is requiredforve hicle transpor ta‐
tion.
* NO
TEDama gedue to to wing away at
exc essively high speeds or over long dis‐
ta nces The driv
etra in could be damaged when tow‐
ing at excessively high speeds or over long
dis tances. #
Atowing speed of 50 km/h must not
be exc eeded. #
Atowing dis tance of 50 km must not be
exc eeded. &
WARNING Risk of accident when towing
a ve hicle which is too heavy
If ano ther vehicle is tow- star ted or towed
aw ay, its weight must not exceed the permis‐
sible gross mass of your ow nve hicle, other‐
wise thefo llowing could occur:
R theto wing eye may become de tach ed.
R theve hicle/trailer combination may
swer veoreve nov erturn. #
If ano ther vehicle is tow- star ted or
to we daw ay, its weight must not exceed
th e permissible gross mass of your own
ve hicle. If a
vehicle must be tow- star ted or towe daw ay,
its permissible gross weight must not exceed the
permissible gross weight of theto wing vehicle. #
Information on the permissible gross mass of
th eve hicle can be found on theve hicle iden‐
tification plate (/ page414). #
Vehicles with automatic transmission: do
not open the driver's door or front passenger
door, otherwise the automatic transmission
automatically shifts toposition j. #
Fittheto wing eye (/ page 390). #
Fasten theto w bar.
* NO
TEDama gedue toincor rect connec‐
tion of theto w bar #
Onlyconnect theto w rope or tow bar to
th eto wing eyes. #
Deactivate the automatic locking mechanism
(/ page 78). #
Do not activate the HOLD function. #
Deactivate tow- aw ay protection
(/ page 93). #
Deactivate Active Brake Assi st
( / page 193). #
Vehicles with automatic transmission:
shift the automatic transmission toposition
i. #
Release the electric parking brake. 388
Breakdown assis tance

&
WARNING Risk of accident due tolimi‐
te d saf ety-re lated functions during the
to wing process
Saf ety-re lated functions are limited or no lon‐
ge rav ailable in thefo llowing situations:
R the ignition is switched off.
R the brake sy stem or po werst eering sys‐
te m is malfunctioning.
R the energy supply or the on-board electri‐
cal sy stem is malfunctioning.
When your vehicle is then towe daw ay, signif‐
icantly more ef fort may be requ ired tosteer
and brake than is no rmally requ ired. #
Use a tow bar. #
Make sure that thesteering wheel can
mo vefreely before towing theve hicle
aw ay. *
NO
TEDama gedue toexcessive tracti ve
po wer If
yo u pull away sharpl y,the tractive po wer
may be too high and theve hicles could be
damaged. #
Pull away slowly and smoo thly. Loading the
vehicle for transport #
Obser vethe no tes on towing away
( / page 387). #
Connect theto w bar totheto wing eye in
order toload theve hicle.
% You can also attach theto w bar tothe trailer
hitch. #
Vehicles with automatic transmission:
shift the automatic transmission toposition
i.
% Ve
hicles with automatic transmission:
th e automatic transmission may be loc ked in
position jintheeve nt of dama getothe
electrical sy stem. Toshift toi , pr ovide the on-board electrical sy
stem with po wer
( / page 384). #
Load theve hicle onto the transpor ter. #
Vehicles with automatic transmission:
shift the automatic transmission toposition
j. #
Use the electric parking brake tosecure the
ve hicle against rolling away. #
Only secure theve hicle bythe wheels.
Ve hicles with ADS PLUS (Adaptive Damping
Sy stem PLUS) &
WARNING Risk of an accident when
transporting vehicles with Adaptive
Damping Sy stem PLUS
When transporting vehicles with Adaptive
Damping Sy stem PLUS, theve hicle/trailer
combination may begin torock andstart to
skid. #
When transporting, ensure that:
R theve hicle has been loaded onto
th e transpor ter cor rectly Breakdown assis
tance 389