2021 MERCEDES-BENZ A-CLASS HATCHBACK ECU

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
e tr
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 Aut 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. #
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- Breakdown assistance
357
357

#
Switch on theve hicle; the steering wheel loc k-
ing may otherwise engage. &
W
WARNING
ARNING Risk of accident due tolimited
saf ety-re lated functions during theto wing
process
Saf ety-re lated functions are limited or no lon-
ge rav ailable in thefo llowing situations:
R theve hicle is switched o..
R the brake system or po wer steering system
is malfunctioning.
R the energy supply or the on-board electri-
cal system is malfunctioning.
When your vehicle is towe daw ay, signi/cantly
more e.ort may be requ ired tosteer and
brake than is normally requ ired. #
Use a tow bar. #
Make sure that the steering wheel can
mo vefreely be fore towing theve hicle
awa y. *
N
NO
OTE
TE Damage due toexcessive tractive
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 slo wlyand smoo thly. Loading t
Loading t
he v
he vehicle f
ehicle f or tr
or transport
anspo rt Hybr
Hybr
id v
id vehicles:
ehicles: transpor tation of vehicles should
only be car ried out byprofessional reco very com-
panies. #
Obser vethe no tes on towing away
( / page 360). #
Connect theto wing device totheto wing eye
in order toload theve hicle.
% You can also attach theto w bar tothe trailer
hitch. #
V
Vehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: shiTthe
automatic transmission toposition i.
% V
Vehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: the
automatic transmission may be loc ked in posi- tion
jintheev ent of damage tothe electri-
cal system. ToshiT toi , pr ovide the on-
board electrical system with po wer
( / page 357). #
V
Vehicles wit
ehicles wit h manual tr
h manual tr ansmission:
ansmission: shiTto
neutral. #
Load theve hicle onto the transpor ter. #
V
Vehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: shiTthe
automatic transmission toposition j. #
V
Vehicles wit
ehicles wit h manual tr
h manual tr ansmission:
ansmission: engage
/rst or reve rsege ar. #
Use the electric parking brake tosecure the
ve hicle against rolling away. #
Only secure theve hicle bythe wheels.
V
V ehicles wit
ehicles wit h adap
h adaptiv
tiv e dam
e dam ping adjus
ping adjustment tment &
W
WARNING
ARNING Risk of an accident when trans-
porting vehicles with adaptive damping
adjustment
When transpo rting vehicles with adaptive
damping adjustment, theve hicle/trailer com-
bination may begin torock and start toskid. 362
362
Breakdown assis
tance

#
Load theve hicle cor rectly onto the
transpor ter. #
Secure theve hicle on all four wheels
with suitable tensioning straps. #
Do not exceed the maximum permissible
speed of 60 km/h when transporting. *
N
NO OTE
TE Damage totheve hicle from secur-
ing it inco rrectly #
ATer loading, theve hicle must be
secured on all four wheels. Otherwise,
th eve hicle could be damaged. #
A minimum dis tance of 20 cm upwards
and 10 cm down wards must be kept to
th e transport platform. #
Secure theve hicle on all four wheels aTer
loading. 4MA
4MA
TIC v
TIC v ehicles/v
ehicles/v ehicles wit
ehicles wit h aut
h automatic tr
omatic tr ans-
ans-
mission
mission #
Make sure that the front and rear axles come
to rest on the same transpor tation vehicle.
* N
NOOTE
TE Damage tothe drive train due to
incor rect positioning of theve hicle #
Do not position theve hicle abo vethe
connection point of the transport vehi-
cle. T
T
o
o wing ey
wing eye st
e st or
orag
ag e location
e location The
towing eye is under the load compartment
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. Breakd
own assistance
363
363

#
Alwaysre place faulty fuses with speci-
/ed new fuses containing the cor rect
amperage. *
N
NO OTE
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 365). *
N
NO OTE
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 365) R
Fuse box in the front passenger foot we ll
(/ page 366)
R Fuse box in the centre of the load compart-
ment (/ page 367) 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
equir uir ements:
ements:
R A dry clo thand a scr ewdriver are available.
Obser vethe no tes on elect rical fuses
(/ page 364).
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. Breakdown assistance
365
365

#
Never /t more than one emer gency
spa rewheel or spare wheel that di.ers
in size. #
Only use an emer gency spa rewheel or
spare wheel brie0y. #
Do not deacti vate ESP ®
. #
Have the emer gency spa rewheel or
spare wheel of a di.erent size replaced
at the nearest quali/ed specialist work-
shop. The new wheel must ha vethe cor-
re ct dimensions. %
The emer gency spa rewheel is secured in the
emer gency spa rewheel bag in the load com-
partment.
Obser vethefo llowing no tes on removing an emer-
ge ncy spa rewheel:
R Before st owing the emer gency spa rewheel,
make sure there is no air leT in the tyre.
If necessar y,allow the air toescape.
R T
T o r
o r elease air fr
elease air fr om t
om the tyr
he tyr e:
e:remo vetheva lve
cap of the tyre. R
Press down the me tal insert in theva lve using
a pointed object, e.g. a pen.
R Screw theva lve cap onto theva lve.
Obser vethefo llowing no tes on /tting an emer-
ge ncy spa rewheel:
R The maximum permissible speed with an
emer gency spa rewheel /tted is 80 km/h.
R Do not /t the emer gency spa rewheel with
snow chains.
R Replace the emer gency spa rewheel aTer six
ye ars at the latest, rega rdless of wear.
R Check the tyre pressure of the emer gency
spa rewheel /tted. Cor rect the pressure as
necessar y.
% The speci/ed tyre pressure is stated on the
label of the emer gency spa rewheel.
% V
V ehicles wit
ehicles wit h a tyr
h a tyre pr
e pressur
essur e loss w
e loss w ar
arning
ning
syst
syst em:
em: if an emer gency spa rewheel is /tted,
th e tyre pressure loss warning system cannot
function reliabl y.Only restart the system
again when the emer gency spa rewheel has
been replaced with a new wheel. V
V
ehicles wit
ehicles wit h a tyr
h a tyre pr
e pressur
essur e monit
e monit or
or ing sy
ing sy s-
s-
t
t em:
em: if an emer gency spa rewheel is /tted, the
tyre pressure monitoring system cannot func-
tion reliabl y.Fo r a few minutes aTer an emer-
ge ncy spa rewheel is /tted, the system may
still display the tyre pressure of there mo ved
wheel. Only restart the system again when the
emer gency spa rewheel has been replaced
with a new wheel.
Be sure toalso obser vethefo llowing fur ther rela-
te d subjects:
R Notes on tyre pressure (/ page 369)
R Tyre pressure table (/ page 370)
R Notes on /tting tyres (/ page 373)
R Fitting an emer gency spa rewheel
(/ page 378) 384 384
Wheels and tyres

6
until the cor rect tyre pressure has been
re ached. #
Unscr ewunion nut 2of /ller hose 1from
th eva lve. #
Screw theva lve cap of the emer gency spa re
wheel onto theva lve again. #
Stow /ller hose 1and plug 3inthe lo wer
section of the tyre in0ation compressor hous-
ing. #
Stow the tyre in0ation compressor in theve hi-
cle. Collapsible spar
Collapsible spar
e wheel
e wheelN
No
ot
tes on t
es on t he collapsible spar
he collapsible spar e wheel
e wheel&
W
WARNING
ARNING Risk of accident caused by
incor rect wheel and tyre dimensions
The wheel or tyre size and the tyre type of the
emer gency spa rewheel or spare wheel and
th e wheel tobe replaced may di.er. The emer-
ge ncy spa rewheel or spare wheel can signi/-
cantly impair driving characteristics of the
ve hicle. To
prev ent hazardous situations: #
Drive carefull y. #
Never /t more than one emer gency
spa rewheel or spare wheel that di.ers
in size. #
Only use an emer gency spa rewheel or
spare wheel brie0y. #
Do not deacti vate ESP ®
. #
Have the emer gency spa rewheel or
spare wheel of a di.erent size replaced
at the nearest quali/ed specialist work-
shop. The new wheel must ha vethe cor-
re ct dimensions. %
The collapsible spare wheel is secured in the
collapsible spare wheel bag in the load com-
partment.
% The collapsible spare wheel is only available in
cer tain countries.
Obser vethefo llowing no tes on /tting an emer-
ge ncy spa rewheel:
R The collapsible spare wheel is an emer gency
spa rewheel which is only suitable for use for a limited period of time and in a
restric ted man-
ner in theev ent of a 0at tyre (e.g. until the
nearest workshop).
R The tyre side walls are folded when in trans-
port mode. Before using the collapsible spare
wheel, in0ate it using the accompanying com-
pressor.
R Check the tyre pressure of the collapsible
spare wheel once /t tedand, if necessar y,
adjust.
R The maximum permissible speed with a col-
lapsible spare wheel /tted is 80 km/h.
R Do not /t the collapsible spare wheel with
snow chains.
R Replace the collapsible spare wheel aTer six
ye ars at the latest, rega rdless of wear.
% V
Vehicles wit
ehicles wit h a tyr
h a tyre pr
e pressur
essur e loss w
e loss w ar
arning
ning
syst
syst em:
em: if a collapsible spare wheel is /tted,
th e tyre pressure loss warning system cannot
function reliabl y.Only restart the system
again when the collapsible spare wheel has
been replaced with a new wheel. 386
386
Wheels and tyres

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions
Front-passenger airbag
enabled See Owner's Man-
ual *T
he front passen ger airbag will be enabled while theve hicle is in motion in thefo llowing situations:
R even when a child, a small adult or an object weighing less than the system weight thre shold is located on the front
passenger seat
R even when the front passenger seat is not occupied
The system may de tect objects or forc es that are adding tothewe ight applied tothe seat. &
W WARNING
ARNING Risk of injury or death when using a child restraint system while the front passenger airbag is ena-
bled
If yo u secure a child in a child restraint system on the front passenger seat and the front passenger airbag is ena-
bled, the front passenger airbag can deploy in theev ent of an accident.
The child could be struck bythe airbag. #
Ensure, bo thbefore and during the journe y,that the status of the front passenger airbag is cor rect.
NEVER use a rear wa rdfacing child restraint on a seat pro tected byan ACTIVE AIRBAG in front of it, DEATH or
SERIOUS INJURY tothe CHILD can occur. #
Stop theve hicle immediately in accordance with the tra1c conditions. #
Make sure that no objects are trapped under the front passenger seat. #
Check the status of automatic front passenger airbag actuation (/ page 57).#
If necessar y,consult a quali/ed specialist workshop immediatel y. Display messages and
warning/indicator lamps
413
413

V
V
ehicle
ehicle Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/conseq uences and
uences andM
MSolutions
Solutions
d
Vehicle is operational
Switch off ignition before
exiting *Y
ou are leaving theve hicle in a ready-to-drive state. #
Get out of theve hicle, secure it against rolling away and take theke y with you. #
Ifyo u do not lea vetheve hicle, switch o. the electrical consumers, e.g. the seat heating. Otherwise, the 12‑V bat-
te ry may dischar geand starting the engine may be possible only with the help of a second battery (jump start).
ï
Check trailer hitch
lock (white display message) *T
he trailer hitch is not operational during a jou rney with a trailer. &
W WARNING
ARNING Risk of an accident if the ball neck is not loc ked
The trailer may become de tach ed. #
Stop theve hicle immediately in accordance with the tra1c conditions. Do not continue driving. #
Uncouple the trailer and secure it against rolling away. #
Initiate a new swivelling procedu reand do not re-couple the trailer until the display message disappears. #
Initiate a new swivel mo vement (/ page 271). #
When the display message disappears, couple up the trailer and drive on.
If th e display message does not disappear, the trailer hitch is malfunctioning and the ball neck is not loc ked. Display messages and
warning/indicator lamps
429
429