2021 MERCEDES-BENZ A-CLASS SALOON engine

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.
If yo u do not intend touse theve hicle over an
ex tended period of time:
R activate standby mode, or
R connect the battery toa battery charger
appr ovedby Mercedes-Benz, or
R consult a quali/ed specialist workshop todis-
connect the battery N No
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 When
charging the battery and during starting
assistance, alw ays use the jump-start connection
point in the engine compartment. *
N
NO OTE
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. 350
350
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. *
N
NO OTE
TE Damage 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.
R Always make sure that nei ther you nor the bat-
te ry is electros tatically charge d. Breakdown assistance
351 351

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 For starting assistance, only use batteries with
a nominal voltage of 12 V.
R The vehicles must not touch.
R P
P e
etr
tr ol engine:
ol engine: only accept starting assistance
if th e engine and exhaust system 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:
Plug-in h
Plug-in h ybr
ybrid:
id:in order tostart, theve hicle
re qu ires a su1cient charge leve l of the high-volt- age battery as
well as a su1cient po wer output of
th e 12 V on-board electrical system.
R The vehicle is secured with the electric par k-
ing brake.
R A
A ut
ut omatic tr
omatic tr ansmission:
ansmission: the transmission is in
position j.
R Manual tr
Manual tr ansmission:
ansmission: the transmission is in
neutral.
R The vehicle and all elect rical consume rsare
switched o..
R The bonnet is open. #
Slide co ver1 of positive clamp 2onthe
jump-starting connection point in the direction
of the ar row. #
Connect positive clamp 2onyour vehicle to
th e positive pole of the donor battery using
th e jump lead/charging cable. Alw ays begin
with positive clamp 2onyour ow nve hicle
/rst. 352
352
Breakdown assis
tance

#
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 pole of the donor bat-
te ry 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: #
Firs t, re mo vethe jump lead/charging cable
from ear thpoint 3and the negative pole of
th e donor batter y,then from positive clamp
2 and the positive pole of the donor batter y. Begin ea
chtime with the contacts on your
ow nve hicle /rst. #
ATer removing the jump lead/charging cable,
close co ver1 of positive clamp 2.
Plug-in h
Plug-in h ybr
ybrid:
id:ifyo ur vehicle has been star ted
with starting assis tance, it may not be possible to
use the electric drive for appr oximately 30
minutes.
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 349).
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 a 0eece batter y.
Fu llve hicle functionality is only guaranteed
with a 0eece batter y.Fo r saf etyre asons,
Mercedes-Benz recommends that you only
use batteries which ha vebeen tested and
appro vedfo ryo ur vehicle byMercedes-Benz.
R Use de tach able parts such as vent hoses,
elbow /ttings or term inal co vers from the bat-
te ry which is tobe 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
353 353

T
T
o
o wing ey
wing eye st
e st or
orag
ag e location
e location The
towing eye is located in the st owage space
under the boot 0oor. F
F
itting and r
itting and r emo
emoving t
ving t heto
he towing eye
wing eye #
Press the mark on co ver1 inwa rds and
re mo ve. #
Screw intheto wing eye clockwise as far as it
will go and tighten.
V
V ehicles wit
ehicles wit h a tr
h a trailer hitc
ailer hitc h:
h:vehicles with a trailer
hitch do not ha veare ar brac ketfo rth eto wing
ey e. Fasten theto w bar tothe trailer hitch. #
Make sure that co ver1 engages in the
bumper when youre mo vetheto wing eye.
* N
NO OTE
TE Damage totheve hicle due toincor-
re ct use of theto wing eye or trailer hitch When a
towing eye or trailer hitch is used to
re co ver a vehicle, theve hicle may be damaged
in the process. #
Only use theto wing eye or trailer hitch to
to w awa y or tow start theve hicle. #
Do not use theto wing eye or trailer hitch
to to wtheve hicle during reco very. T
T
o
o w
w -st
-st ar
arting t
ting t he v
he vehicle
ehicle V V
ehicles wit ehicles wit h aut
h automatic tr
omatic tr ansmission
ansmission
* NO
NOTE
TEDamage tothe automatic transmis-
sion due to tow-starting The au
tomatic transmission may be damaged
in the process of tow- starting vehicles with
automatic transmission. #
Vehicles with automatic transmission
must not be tow- star ted. #
Vehicles with an automatic transmission must
not be tow- star ted.
V V ehicles wit ehicles wit h manual tr
h manual tr ansmission
ansmission #
Obser vethe no tes on towing away
( / page 356). #
If necessar y,allow the engine and exhaust
system tocool down. #
Swit chon the ignition. #
Engage second gear. #
Release the electric parking brake. Breakdown assistance
359
359

#
Tow- start theve hicle while the clutch pedal is
fully depressed. #
Slowly re leasethe clutch pedal. #
Immediately shiT toneutral if the engine
starts. #
Stop theve hicle in accordance with the tra1c
conditions. #
Remo vetheto w bar. #
Remo vetheto wing eye. #
Have theve hicle checked at a quali/ed spe-
cialist workshop. Electr
Electr
ical fuses
ical fuses N
No
ot
tes on electr
es on electr ical fuses
ical fuses &
W
WARNING
ARNING Risk of accident and injury due
to ove rloaded lines
If yo u manipulate or bridge a faulty fuse or if
yo ure place it with a fuse with a higher amper-
age, the electric line could be overloaded.
This could result in a /re. #
Alwaysre place faulty fuses with speci-
/ed new fuses containing the cor rect
amperage. *
N
NOOTE
TE Damage due toincor rect fuses Electrical components or systems may be
damaged
byincor rect fuses, or their function-
ality may be signi/cantly impaired. #
Only use fuses that ha vebeen appr oved
by Mercedes-Benz and which ha vethe
cor rect fuse rating. Blown fuses must be
replaced with fuses of the
same rating, whi chyou can recognise bythe col-
our and the label. The fuse ratings and fur ther
information tobe obser ved can be found in the
fuse assignment dia gram.
F F use assignment diagr
use assignment diagr am:
am:onthe fuse box in the
engine compartment (/ page 361). *
N
NOOTE
TE Damage or malfunctions caused by
moisture Moisture may cause damage
tothe electrical
system or cause it tomalfunction. #
When the fuse box is open, make sure
th at no moisture can enter the fuse box. #
When closing the fuse box, make sure
th at the seal of the lid is positioned cor-
re ctly on the fuse box. If
th e ne wlyinser ted fuse also blo ws, ha vethe
cause traced and recti/ed at a quali/ed specialist
wo rkshop.
Ensure thefo llowing before replacing a fuse:
R The vehicle is secured against rolling away.
R All electrical consume rsare switched o..
R The vehicle is switched o..
The elect rical fuses are located in various fuse
bo xes:
R Fuse box in the engine compartment on the
leT-hand side of theve hicle, when vie wed in
th e direction of tr avel (/ page 361) 360
360
Breakdown assistance

R
Fuse box in the front passenger foot we ll
(/ page 361)
R Fuse box in the centre of the boot
(/ page 362) Opening and closing t
Opening and closing t
he fuse bo
he fuse box in t
x in the engine
he engine
com
com par
partment
tment R
R
eq
eq uir
uir ements:
ements:
R A dry clo thand a scr ewdriver are available.
Obser vethe no tes on elect rical fuses
(/ page 360).
Opening
Opening &
W
WARNING
ARNING Risk of injury from using the
windscreen wipers when the bonnet is
open
If th e windscreen wipers start moving when
th e bonnet is open, you could be trapped by
th e wiper linkage. #
Always switch o. the windscreen wipers
and vehicle before opening the engine
bonnet. #
Open the bonnet. #
Remo veany existing moisture from the fuse
box using a dry clo th. #
Loosen scr ews1. #
Press clamps 2and liT the fuse box lid up
and out. The fuse assignment diag
ram is in a recess on the
side of the fuse box.
Closing Closing #
Check whe ther the seal is positioned cor rectly
in the lid. #
Place the lid on the fuse box. #
Make sure that clamps 2engage. #
Tighten scre ws1. #
Close the bonnet. Opening and closing t Opening and closing t
he fuse bo
he fuse box in t
x in the fr
he front
ont
passeng
passeng er f
er foo
ootw
twell
ell Obser
vethe no tes on elect rical fuses
(/ page 360). Breakdown assistance
361
361

N
N
o
ot
tes on t
es on t ec
echnical data
hnical data
* NO
NOTE
TEMercedes-AMG vehicles #
Obser vethe no tes in the Supplement.
Yo u could otherwise failto recognise
dangers. The
tech nical data was de term ined in accordance
with EU Directives. The data stated only applies to
ve hicles with standard equipment. You can obtain
fur ther information from a Mercedes-Benz Service
Centre.
Onl Onl y f
y for cert
or cert ain countr
ain countr ies:
ies:you can /n dvehicle-
speci/c vehicle data in theCO C documents (CER-
TIFIC ATE OF CONFORMITY). These documents
are deli vered with your vehicle. On-boar
On-boar
d electr
d electronics
onics N
No
ot
tes on t
es on t am
amper
per ing wit
ing wit h t
h t he engine electr
he engine electr onics
onics *
N
NOOTE
TE Prematu rewe arthro ugh improper
maintenance Improper maintenance may cause
vehicle
components towe ar more quickly and the
ve hicle's operating permit may be in validated. #
Always ha veworkon the engine elec-
tronics and related components car ried
out at a quali/ed specialist workshop. T
T
w
w o-wa
o-wa y r
y radios
adios N
No
ot
tes on
es on /tting
/tting tw
two-wa
o-wa y r
y radios
adios &
W
WARNING
ARNING Risk of accident due to
improper workon two-w ayradios
If two-w ayradios are manipulated or retro/t-
ted incor rectl y,the electromagnetic radiation
from the two-w ayradios can inter fere with the
ve hicle elect ronics and jeopardise the operat-
ing saf ety of theve hicle. #
You should ha veall workon electrical
and electronic components car ried out
at a quali/ed specialist workshop. &
W
WARNING
ARNING Risk of accident due to
improper operation of two-w ayradios
If yo u use two-w ayradios in theve hicle
improper ly,th eir electromagnetic radiation
can disrupt theve hicle's elect ronics. This is
th e case in thefo llowing situations, in particu-
lar:
R The two-w ayradio is not connected toan
ex terior aerial.
R The exterior aerial is /tted incor rectly or is
not a lo w-re0ection aerial.
This could jeopardise the operating saf ety of
th eve hicle. #
Have the lo w-re0ection exterior aerial /t-
ted at a quali/ed specialist workshop. #
When operating two-w ayradios in the
ve hicle, alw ays connect them tothe lo w-
re 0ection exterior aerial. Te
ch nical data
381
381