2021 MERCEDES-BENZ C-CLASS CABRIOLET battery

The Mercedes-Benz emer
gency call sy stem is
av ailable for at least tenye ars starting from the
manufacturing date.
The ignition must be switched on before an auto‐
matic emergency call can be made.
% The Mercedes-Benz emer gency call sy stem
is activated at thefa ctor y.
Overview of the Mercedes-Benz emer gency
call sy stem
The Mercedes-Benz emer gency call sy stem can
help todecisively reduce the time between an
accident and the ar riva l of emer gency services
at the site of the accident. It helps locate an
accident site in places that are dif ficult to
access.
The emer gency call can be made au tomatical ly
( / page 319) or manually (/ page 320). Only
make emer gency calls if you or others are in
need of rescue. Do not make an emer gency call
in theeve nt of a breakdown or a similar situa‐
tion.
Displ ays in the media display
SOS READY: eCall available SOS NOT READY:
the ignition is not on or eCall
is not available.
During an active emer gency call, Gappears
in the displa y.
Yo u can find more information on there gional
av ailability of eCall at: https://www.mercedes-
benz-mobile.com/ext ra/ecall/
% Ifth ere is a malfunction in the emer gency
call sy stem (e.g. a fault with the speaker,
microphone, airbag, SOS button), a cor re‐
sponding message appears inthe multifunc‐
tion display of the instrument clus ter.
Tr iggering an automatic emer gency call
Re quirements:
R The ignition is switched on.
R The star ter battery is suf ficiently charge d.
If re stra int sy stems such as airbags or seat belt
te nsioners ha vebeen activated af ter an acci‐
dent, the Mercedes-Benz emer gency call sy stem
may automatically initiate an emer gency call. The emergency call has been made:
R
Avo ice connection is made tothe Mercedes-
Benz emer gency call centre.
R A messa gewith accident data is transmitted
to the Mercedes-Benz emer gency call centre.
The Mercedes-Benz emergency call centre
can transmit theve hicle position data toone
of the public emer gency services call cen‐
tres.
R In cer tain situations data is also transmitted
in thevo ice channel tothe Mercedes-Benz
emer gency call centre.
This allo wsmeasu resfo rre scue, reco very or
to wing toa Mercedes-Benz Service Cent reto
be initiated quickl y.
The SOS button in theov erhead control panel
fl ashes until the emer gency call is finished.
It is not possible toimmediately end an auto‐
matic emer gency call.
If th e Mercedes-Benz emer gency call sy stem
cann otconnect tothe Mercedes-Benz emer‐
ge ncy call centre, the emer gency call is au tomat‐ Multimedia sy
stem 319

R
Vehicle identification number
R Vehicle drive type
R Number of people de term ined tobe in the
ve hicle
R Whe ther Mercedes me connect is available
or not
R Whe ther the emer gency call was initiated
manually or automatically
R Time of the accident
R Language setting on the multimedia sy stem
Fo r accident clarification purposes, thefo llowing
measures can be take n up toan hour af terthe
emer gency call has been initia ted:
R The cur rent vehicle position can be de ter‐
mined.
R Avo ice connection totheve hicle occupants
can be es tablished
% ForRu ssia: various functions, e.g. receiving
traf fic information, cannot be used for up to
two hou rsafte r sending an emergency call. Self diagnosis function of
the emer gency call
sy stem
Yo ur car verifies the operability of the emer‐
ge ncy call sy stem each time the ignition is ON.
In case of sy stem failure, you will be informed
with text messa geon the instrument clus ter and
with red indicator SOS NOT READY onthe dis‐
pla y.
Please, make sure, that during 30 seconds af ter
switching ignition ON there d indicator SOS
NOT READY inthe upper right corner of display
is switched OFF, this means the emer gency call
sy stem passed diagnostics successfully.
St arting/ending ERA-GLONASS test mode
Re quirements:
R The star ter battery is suf ficiently charge d.
R The ignition is switched on.
R The vehicle has been stationary for at least
one minute.
% The test mode is cur rently available in the
fo llowing countries, forex ample:
R Russia R
Belarus
R Kazakh stan
R Armenia
R Kyrgyzs tan #
Tostart thete st mode: press and hold the
~ button on the multifunction steering
wheel for at least five seconds.
The test mode is star ted and automatically
ends af terth e language test has been per‐
fo rm ed. #
Toend thete st mode manuall y:switch off
th e ignition.
The test mode is ended. Multimedia sy
stem 321

fi
ed based on the actual operating conditions
and/or loads.
Examples of arduous operating conditions:
R regular city driving with frequent intermedi‐
ate stops
R mainly short-dis tance driving
R frequent operation in mountainous terrain or
on poor road sur faces
R when the engine is of ten le ftidling for long
periods
R operation in particula rly dusty conditions
and/or if air-recirculation mode is frequently
used
In these or similar operating conditions, ha vethe
interior air filter, engine air cleaner, engine oil
and oil filter etc. changed more frequent ly. The
ty re s must be checked more frequently if the
ve hicle is operated under increased loads. Fur‐
th er information can be obtained at a qualified
specialist workshop. Battery disconnection periods
The ASS
YST PLUS service inter val display can
calculate the service due date only when the
battery is connec ted. #
Notedown the service due date displa yed on
th e instrument display before disconnecting
th e battery (/ page 354). Engine compartment
Ac
tive bonn et(pedestrian pr otection) Operation of
the active bonnet (pedestrian
pr otection)
In cer tain accident situations, the actuation of
th e active bonn etreduces therisk of injury to
pedestrians. The rear area of the bonn etis
ra ised byappr oximately 85 mm.
Fo rth e drive tothewo rkshop, reset the actuated
active bonn etyourself (/ page 355).
Af terth e active bonn ethas been actuated,
pedestrian pr otection may be limited.
Ha ve the full functionality of the active bonn et
re stored in a qualified specialist workshop. Re
setting the active bonnet &
WARNING Risk of bu rns from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler and parts of theex haust sy stem. #
Allow the engine tocool down and only
to uch co mponent parts described in
th efo llowing. Maintenance and care
355

Battery (vehicle)
Note
s onthe12 V battery &
WARNING Risk of an accident due to
wo rkcar ried out incor rectly on the bat‐
te ry
Wo rkcar ried out incor rectly on the battery
can, forex ample, lead toa short circuit. This
can restrict functions releva nt for saf ety sys‐
te ms and impair the operating saf ety of your
ve hicle.
Yo u could lose cont rol of theve hicle in the
fo llowing situations in particular:
R when braking
R intheeve nt of ab rupt steering manoeu‐
vres and/or when theve hicle's speed is
not adap tedto thero ad conditions #
Intheeve nt of a sho rtcircuit or a simi‐
lar incident, contact a qualified special‐
ist workshop immediately. #
Do not drive on. #
Alw ays ha vewo rkon the battery car ried
out at a qualified specialist workshop. R
Further information on ABS (/ page170)
R Further information on ESP ®
(/ page 170)
Fo r saf etyre asons, Mercedes-Benz recommends
th at you on lyuse bat teries which ha vebeen tes‐
te d and appr ovedfo ryo ur vehicle byMercedes-
Benz.
All vehicles except vehicles with a lithium-
ion battery &
WARNING Risk ofexplosion due toelec‐
tros tatic charge
Electros tatic charge can igni tethe highly
ex plosive gas mixture in the batter y. #
Todischar geany electros tatic charge
th at may ha vebuilt up, touch the me tal
ve hicle body before handling the bat‐
te ry. The highly
flammable gas mixture is created
while the battery is charging and during starting
assis tance. &
WARNING Danger of chemical burns
from the battery acid
Battery acid is caustic. #
Avoid contact with the skin, eyes or
clo thing. #
Do not lean overth e batter y. #
Do not inhale battery gases. #
Keep children away from the batter y. #
Immedia tely rinse battery acid off thor‐
oughly with plenty of clean water and
seek medical attention immediately. Breakdown assi
stance 381

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