2021 MERCEDES-BENZ E-CLASS CABRIOLET battery

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 control of theve hicle in thefo l-
lowing situations in particular:
R when braking
R intheev ent of abrupt steering manoeuvres
and/or when theve hicle's speed is not
adap tedto thero ad conditions #
Intheev ent of a short circuit or a similar
incident, contact a quali/ed specialist
wo rkshop immediatel y. #
Do not drive on. #
Always ha veworkon the battery car ried
out at a quali/ed specialist workshop. R
Further information on ABS (/ page 185)
R Further information on ESP ®
(/ page 186)
Fo r saf etyre asons, Mercedes-Benz recommends
th at you only use batteries which ha vebeen tes-
te d and appr ovedfo ryo ur vehicle byMercedes-
Benz. All v
All v ehicles ex
ehicles excep
cep t v
t vehicles wit
ehicles wit h a lit
h a lithium-ion bat-
hium-ion bat-
t
t ery
ery &
W
WARNING
ARNING Risk ofexplosion due toelec-
trostatic charge
Electrostatic charge can ignite the highly
ex plosive gas mixtu reinthe batter y. #
Todischar geany elect rostatic charge
th at may ha vebuilt up, touch the me tal
ve hicle body before handling the batter y. The high
ly0ammable gas mixtu reis created while
th e battery is charging and during starting assis-
ta nce. &
W
WARNI NG
ARNI NGDanger of chemical burns from
th e 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. #
Immediately rinse bat tery acid o. thor-
oughly with plenty of clean water and
seek medical attention immediatel y. All v
All v
ehicles
ehicles
+ ENVIR
ENVIR
ONMENT
ONMENT AL NO
AL NOTE
TEEnvironmental
damage due toimproper disposal of bat-
te ries Batteries contain pollutants. It is
illegal todispose of them with the household
ru bbish. #
Dispose of batteries in an
environmentally responsible manner.
Ta ke dischar ged batteries toaqu ali/ed
specialist workshop or toa collection
point for used batteries. Breakdown assistance
323
323

If
yo u ha vetodisconnect the 12 V batter y,con-
ta ct a quali/ed specialist workshop.
Comply with saf ety no tes and take protective
measures when handling batteries. Risk of
explosion. Fire
, naked 0ames and smoking are
prohibi ted when handling the batter y.
Av oid creating spar ks. Electrolyte or battery acid is cor
rosive.
Av oid contact with the skin, eyes or
clo thing. Wear suitable pr otective
clo thing, in particular glo ves, an apron
and a face mask. Immediately rinse
electrolyte or acid splashes o. with
clean water. Consult a doctor if neces-
sar y. We
ar saf ety glasses. Ke
ep children away. Obser
vethis Owner's Manual.
Obser vethefo llowing if you do not intend touse
th eve hicle over an extended period of time:
R Activate standby mode.
R Alternativel y:connect the battery toa battery
ch arge r appr ovedby Mercedes-Benz or con-
sult a quali/ed specialist workshop todiscon-
nect the batter y. N N
o
ot
tes on st
es on st ar
arting assist
ting assist ance and c
ance and c har
harging t
ging t he 12
he 12
V batt
V batt ery
ery All v All v
ehicles
ehicles
When charging the battery and during starting
assistance, alw ays use the jump-start connection
point in the engine compartment. *
N
NOOTE
TE Damage tothe battery from over-
vo ltage When
charging using a battery charge r without
a re striction of the maximum charging voltage,
th e battery or the on-board electronics can be
damaged. #
Only use battery charge rs with a maxi-
mum charging voltage of 14.8 V. &
W
WARNI NG
ARNI NGRisk of explosion due tohydro-
ge nga s igniting
If, when charging a batter y,there is a short
circuit or spar ksstart toform ,th ere is a dan-
ge r of hydrogen gas igniting. #
Take care that the positive clamp con-
nected toa battery does not come into
contact with vehicle parts. #
Never place me tal objects or tools on a
batter y. #
When connecting and disconnecting the
batter y,alw ays obser vethe sequence of
battery clamps described. 324
324
Breakdown assistance

#
Take care toonly connect battery term i-
nals of identical polarity when receiving
starting assistance. #
Obser vethe sequence described for
connecting and disconnecting the jump
leads when receiving starting assistance. #
Do not connect or disconnect the bat-
te ry term inals while the engine is run-
ning. &
W
W ARNI NG
ARNI NGRisk of explosion due toexplo-
sive mixture of gases
An explosive mixture of gases can escape
from the battery during charging and starting
assis tance. #
Fire , naked 0ames, smoking and creating
spar ksmust be avoided. #
Make sure there is adequate ventilation. #
Do not stand overth e batter y. &
W
WARNI NG
ARNI NGRisk of explosion from a frozen
battery
A dischar ged battery may freeze at temp era-
tures slightly abo veor below freezing point.
During starting assistance or battery charging,
battery gas can be released. #
Always allow a battery tothaw before
ch arging it or per form ing starting assis-
ta nce. If
th e indicator/warning lamps in the inst rument
clus ter do not light up at low temp eratures, it is
ve ry likely that the dischar ged battery has frozen.
In this case you may neither jump-start theve hi-
cle nor charge the batter y.
The service life of a bat tery that has been thawed
may be dramatically shor tened. The starting char-
acteristics may be impaired, especially at low
te mp eratures.
It is recommended that you ha veath awe d battery
ch ecked at a quali/ed specialist workshop. All v
All v ehicles
ehicles
* NO
NOTE
TEDamage caused bynume rous or
ex tended attem ptsto start the engine Numerous or
extended attem ptsto start the
engine may damage the catalytic con verter
due tonon-combusted fuel. #
Avoid numerous and extended attem pts
to start the engine. Obser
vethefo llowing points during starting assis-
ta nce and when charging the batter y:
R Only use undamaged jump lead/charging
cables with a su1cient cross-section and
insulated term inal clamps.
R Non-insulated parts of thete rm inal clamps
must not come into contact with other me tal
parts while the jump lead/charging cable is
connected tothe battery/jump-start connec-
tion point.
R The jump lead/charging cable must not come
into contact with any parts which may mo ve
when the engine is running. Breakdown assistance
325 325

R
Always make sure that nei ther you nor the bat-
te ry is electrostatically charge d.
R Keep awa y from /re and naked 0ames.
R Do not lean overth e batter y.
Obser vethe additional following points when
ch arging the batter y:
R Only use battery charge rs tested and
appro vedfo r Mercedes-Benz.
R Read the battery charge r's operating inst ruc-
tions before charging the batter y.
Obser vethe additional following points during
starting assistance:
R Starting assis tance may only be pr ovided
using vehicles, batteries or other jump start
devices with a nominal voltage of 12 V.
R The vehicles must not touch.
R V
V ehicles wit
ehicles wit h a pe
h a petr
trol engine:
ol engine: jump-start the
ve hicle only when the engine and exhaust sys-
te m are cold. S
S
t
tar
ar ting assist
ting assist ance and c
ance and c har
harging t
ging t he 12 V batt
he 12 V batt ery
ery R R
eq eq uir
uir ements:
ements:
R The vehicle is secured with the electric par k-
ing brake.
R V
Vehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: the
transmission is in position j.
R The vehicle and all elect rical consume rsare
switched o..
R The bonnet is open. Example: engine compartment
#
Slide co ver1 of positive contact 2onthe
jump-starting connection point in the direction
of the ar row. #
Connect positive contact 2onyour vehicle
to the positive term inal of the donor battery
using the jump lead/charging cable. Alw ays326
326
Breakdown assistance

begin with positive contact
2onyour own
ve hicle /rst. #
Dur
During st
ing st ar
arting assist
ting assist ance:
ance:startthe engine of
th e donor vehicle and run at idle speed. #
Connect the negative term inal of the donor
battery and ear thpoint 3ofyour ow nve hicle
by using the jump lead/charging cable. Begin
with the donor battery /rst. #
Dur
During st
ing st ar
arting assist
ting assist ance:
ance:startthe engine of
yo ur ow nve hicle. #
Dur
During t
ing t he c
he char
harging pr
ging pr ocess:
ocess: startthech arg-
ing process. #
Dur
During st
ing st ar
arting assist
ting assist ance:
ance:letthe engines run
fo r se veral minutes. #
Dur
During st
ing st ar
arting assist
ting assist ance:
ance:before disconnect-
ing the jump lead, switch on an electrical con-
sumer on your ow nve hicle, e.g. there ar win-
dow heater or lighting.
When the starting assistance/charging process is
comple te, per form thefo llowing steps: #
Firs t, re mo vethe jump lead/charging cable
from ear thpoint 3and the negative term inal of
the donor batter y,then from positive con-
ta ct 2 and the positive term inal of the donor
batter y.Begin ea chtime with the contacts on
yo ur ow nve hicle /rst. #
ATer removing the jump lead/charging cable,
close co ver1 of positive contact 2.
Fu rther information can be obtained at a quali/ed
specialist workshop. R
R
eplacing t
eplacing t he 12 V batt
he 12 V batt ery
ery #
Obser vethe no tes on the 12 V battery
(/ page 322).
Mercedes-Benz recommends that you ha vethe
12 V battery replaced at a quali/ed specialist
wo rkshop, e.g. at a Mercedes-Benz Se rvice
Centre.
Obser vethefo llowing no tes if youwa nttoreplace
th e battery yourself:
R Alwaysre place a faulty battery with a battery
which meets the speci/c vehicle requ ire-
ments. The
vehicle is equipped with an AGMtech nol-
ogy bat tery (Absorbent Glass Mat) or a lith-
ium-ion batter y.Fu llve hicle functionality is
only guaranteed with an AGM bat tery or lith-
ium-ion batter y.Fo r saf etyre asons, Mercedes-
Benz recommends that you only use batteries
which ha vebeen tested and appro vedfo ryo ur
ve hicle byMercedes-Benz.
R Carryove r de tach able parts, such as vent
hoses, elbow /ttings or term inal co vers from
th e battery being replaced.
R Make sure that theve nt hose is alw ays con-
nected tothe original opening on the side of
th e batter y.
Fi t 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. Breakd
own assistance
327 327

T
T
o
o w
w -st
-st ar
arting or to
ting or towing away
wing away P
P
er
er mitt
mitt edto
ed towing met
wing met hods (non plug-in h
hods (non plug-in h ybr
ybrid)
id) *
N
NOOTE
TE Damage from automatic braking If one of
thefo llowing functions is switched
on, theve hicle brakes automatically in cer tain
situations:
R Active Brake Assist
R Active Distance Assist DISTRONIC
R HOLD function
R Active Parking Assist
To avoid damage totheve hicle, deactivate
th ese systems in thefo llowing or similar situa-
tions: #
during towing #
in a car wash Mercedes-Benz
recommends transporting your
ve hicle in the case of a breakdown, rather than
to wing it away.
Fo rto wing, use a tow rope or tow bar with bo th
axles on thegr ound. Do not use tow bar systems. *
N
NO OTE
TE Damage totheve hicle due to tow-
ing awa y incor rectly #
Obser vethe inst ructions and no tes on
to wing away. V
V
ehicles wit
ehicles wit h r
h rear wheel dr
ear wheel dr ive
ive P
P
er
er mitt
mitt edto
ed towing met
wing met hods
hods
Bo th axles on
th egr ound Ye
s, maximum 50 km at
50 km/h
Fr ont axle
ra ised No
Re ar axle
ra ised Ye
s, if the steering wheel is
/xed in the centre position
with a steering wheel lock 4MA
4MA
TIC v
TIC v ehicles
ehicles P
P
er
er mitt
mitt edto
ed towing met
wing met hods
hods
Bo th axles on
th egr ound Ye
s, maximum 50 km at
50 km/h
Fr ont axle
ra ised No
Re ar axle
ra ised No T
T
o
o wing wit
wing wit h a r
h a raised axle:
aised axle: towing should be per-
fo rm ed byato wing compan y. T
T
o
o wing t
wing t he v
he vehicle wit
ehicle wit h bot
h both axles on t
h axles on t hegr
he ground
ound #
Obser vethe no tes on the permitted towing
me thods (/ page 328). #
Make sure that the battery is connected and
ch arge d.
Obser vethefo llowing points when the battery is
dischar ged:
R the engine cannot be star ted328
328
Breakdown assistance

K
K
e
ey
y Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions
Á
Replace key *H
aveth eke yre placed. #
Consult a quali/ed specialist workshop.
Á
Change key batteries *T
hekey battery is dischar ged. #
Replace the battery (/ page 76).
Á Key not detected (white dis-
play message) *T
hekey is cur rently unde tected. #
Change the location of theke y in theve hicle. #
Ifth eke y is still not recognised, place it in the slot for starting with theke y (/ page 155). Display messages and
warning/indicator lamps
375
375

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions
K
Open/close soft top com-
pletely *T
he soT top is not loc ked. If you drive at speeds greater than 60 km/h you cannot open or close the soT top. #
Do not drive at speeds greater than 60 km/h. #
Fully open or close the soT top.
K
12 V battery See Owner's
Manual *T
he on-board elect rical system voltage is too lo w. #
Start theve hicle.
J
Close boot separator *T
he boot separator is open. #
Close the boot separator. 378 378
Display messages and
warning/indicator lamps