MERCEDES-BENZ B-CLASS HATCHBACK 2021 Owners Manual

#
Neverto uch damaged components of
th e high-voltage on-board electrical sys-
te m. #
ATer an accident, do not touch any com-
ponents of the high-voltage on-board
electrical system. #
ATer an accident, ha vetheve hicle trans-
por tedawa y. #
Have the components of the high-voltage
on-board electrical system checked at a
qu ali/ed specialist workshop and
re placed if necessar y.R
R
eq
eq uir
uir ements:
ements:
Only disconnect the high-voltage on-board electri-
cal system manually in thefo llowing situations:
R The 0075 restraint system warning lamp lights
up in the Instrument Displa y,e.g. aTer an
accident.
R The vehicle is badly damaged, e.g. aTer an
accident, and there straint system co mpo-
nents ha venot been triggered. T
T
o oper
o oper at
ate t
e t he high-v
he high-v olt
oltag
age disconnect de
e disconnect de vice
vice #
Switch o. theve hicle. #
ShiT the transmission toposition 005D. #
Apply the electric parking brake. #
Secure theve hicle against rolling away (see
th eve hicle Owner's Manual). #
Open the bonnet. #
Press release tab1 inthe direction of the
ar ro w and pull it out. #
Pull high- voltage disconnect device 2inthe
direction of the ar row until it engages.
The high- voltage on-board electrical system is
switched o..
All workon thehy brid drive system (including
aTer disconnecting the high-voltage on-board
electrical system manually) may only be car ried
out byaqu ali/ed specialist workshop. Switc
Switc
hing on t
hing on t he pow
he power suppl
er suppl y or t
y or the v
he vehicle
ehicle &
W
WARNING
ARNING Risk of accident and injury due
to leaving children unattended in theve hi-
cle
If ch ildren are leT unattended in theve hicle,
th ey could, in particular:
R open doors, thereby endangering other
persons or road users.
R get out and be struck byoncoming tra1c. 168
168
Driving and parking

R
operate vehicle equipment and become
trapped, forex ample.
In addition, thech ildren could also set the
ve hicle in motion by,fo rex ample:
R releasing the parking brake.
R changing the transmission position.
R starting theve hicle. #
Never lea vechildren unattended in the
ve hicle. #
When leaving theve hicle, alw aysta ke the
ke y with you and lock theve hicle. #
Keep theve hicle key out of there ach of
ch ildren. R
R
eq
eq uir
uir ements:
ements:
R The key is in theve hicle and is recognised.
R V
Vehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: The
brake pedal is not depressed.
R V
Vehicles wit
ehicles wit h manual tr
h manual tr ansmission:
ansmission: The clutch
pedal is not depressed. #
T To switc o switc h on t
h on the pow
he pow er supply
er supply :
:press button
1 once.
Yo u can, forex ample, activate the windscreen
wiper.
The po wer supply is switched o. again if thefo l-
lowing conditions are met:
R You open the driver's door.
R you press button 1twice more. #
T
To switc
o switc h on t
h on the v
he vehicle:
ehicle: press button 1
twice.
Indicator and warning lamps go on in the
inst rument cluster.
The vehicle is switched o. again if one of thefo l-
lowing conditions is met:
R V
V ehicles wit ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: You do
not start theve hicle within 15 minutes and the
transmission is in position 005Dorthe electric
parking brake is applied.
R V
Vehicles wit
ehicles wit h manual tr
h manual tr ansmission:
ansmission: You do not
start theve hicle within 15 minutes and the
electric parking brake is applied.
R you press button 1once. S
S
t
tar
ar ting t
ting t he v
he vehicle
ehicle S S
t
tar
ar ting t
ting t he v
he vehicle wit
ehicle wit h t
h the st
he st ar
art/st
t/st op butt
op butt on
on &
D DAN
AN GER
GER Risk of fatal injuries caused by
ex haust gases
Combustion engines emit poisonous exhaust
ga ses such as carbon monoxide. Inhaling Driving and parking
169
169

th
ese exhaust gases is hazardous tohealth
and leads topoisoning. #
Never lea vetheve hicle or, if present, the
stationa ryheater running in an enclosed
space without su1cient ventilation. &
W
WARNI NG
ARNI NGRisk of /re due to0ammable
material in the engine compartment or the
ex haust system
Flammable materials may ignite. #
Therefore, check regula rly th at there are
no 0ammable materials in the engine
compartment or on theex haust system. R
R
eq
eq uir
uir ements:
ements:
R The key is in theve hicle and is recognised. #
V
Vehicles wit
ehicles wit h manual tr
h manual tr ansmission:
ansmission: Depress
th e clutch pedal. #
V Vehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: ShiT
th e transmission toposition 005Dor005C. #
Depress the brake pedal and press button 1
once. #
Ifth eve hicle does not start: switch o. non-
essential consumers and press but ton1
once. #
Ifth eve hicle still does not start and the dis-
play message Place the key in the marked
space See Owner's Manual appears inthe
inst rument displa y: starttheve hicle with the
ke y in the mar ked space (emer gency ope ra-
tion mode) (/ page 170).
% You can switch o. theve hicle while driving. To
do this, press button 1for about thre e sec-
onds or bypressing button 1thre e times
within thre e seconds. Be sure toobser vethe
saf ety no tes under "Driving tips"
(/ page 173).
Obser veany information rega rding display mes-
sages that can be displ ayed on the inst rument
displa y.
S
S t tar
ar ting t
ting t he v
he vehicle wit
ehicle wit h t
h the ke
he key in t
y in t he mark
he mark ed
ed
space (emerg
space (emerg ency oper
ency oper ation mode)
ation mode)
If th eve hicle does not start and thePlace the
key in the marked space See Owner's Manual
message appears in the inst rument displa y,you can start
theve hicle in emer gency ope ration
mode. Mar
ked space (e xample with cup holder without
co ver) #
Open the co ver of the mar ked space 2if
necessar y. #
Make sure that the mar ked space 2is
em pty. 170 170
Driving and parking

#
Remo vetheke y1 from theke yring. #
Place theke y1 inthe mar ked space 2on
th e symbol 3.
The vehicle will start aTer a short time.
When youre mo vetheke y1 from the mar ked
space 2,theve hicle can be driven. For fur-
th er engine starts ho wever,theke y1 must
be located in the mar ked space 2onthe
symbol 3during the entire journe y. #
Have theke y1 checked at a quali/ed spe-
cialist workshop.
If t
If t he v
he v ehicle does no
ehicle does no t st
t st art:
art: #
Place theke y1 inthe mar ked space 2and
lea veitth ere. #
V
Vehicles wit
ehicles wit h manual tr
h manual tr ansmission:
ansmission: Depress
th e clutch pedal. #
Depress the brake pedal and start theve hicle
using the start/s top button.
% You can switch on the po wer supply or the
ve hicle with the start/s top button. Obser
veany information rega rding display mes-
sages that can be displ ayed on the inst rument
displa y. S
S
t
tar
ar ting t
ting t he v
he vehicle via R
ehicle via R emot
emote Online Ser
e Online Ser vices
vices Cooling or heating t
Cooling or heating t
he v
he vehicle int
ehicle int er
erior bef
ior bef ore
ore
st
st ar
ar ting t
ting t he jour
he jour ney
ney
Ensu rethefo llowing before starting the engine:
R The legal stipulations in the area where your
ve hicle is par ked allow engine starting via
smartphone.
R It is safe tostart and runth e engine where
yo ur vehicle is par ked.
R The fuel tank is su1cient lyfull.
R The star ter battery is su1ciently charge d.
Char
Char ging t
ging t he st
he start
arter batt
er batt er
ery bef
y bef or
ore st
e st ar
arting t
ting t he
he
jour
jour ney
ney
Yo u can receive a message on your smartphone
when the state of charge ofthe star ter battery is
lo w. You can then start theve hicle with the smart-
phone tocharge the batter y.The vehicle is auto-
matically switched o. aTer ten minutes. Ensure
thefo llowing before starting the engine:
R The legal stipulations in the area where your
ve hicle is par ked allow engine starting via
smartphone.
R It is safe tostart and runth e engine where
yo ur vehicle is par ked.
R The fuel tank is su1cient lyfull.
S
S t
tar
ar ting t
ting t he v
he vehicle (R
ehicle (R emot
emot e Online)
e Online) &
W
WARNING
ARNING Risk of crushing or entrapment
due tounintentional starting of the engine
Limbs could be crushed or trapped if the
engine is star ted unintentionally during service
or maintenance work. #
Always secure the engine against unin-
te ntional starting before ca rrying out
main tenance or repair work. R
R
eq
eq uir
uir ements:
ements:
R Park position 005Dis selected.
R The anti-theT alarm system is not activated.
R The hazard warning light system is switched
o.. Driving and parking
171
171

R
The bonnet is closed.
R The doo rsare closed and loc ked.
R The windo wsand sliding sunroof are closed. #
Start theve hicle using the smartphone.
ATer every engine start, the engine runs for
te n minutes.
Yo u can car ryout a maximum of two consecutive
starting attem pts. You must start the engine with
th eke y before trying tostart theve hicle again
with the smartphone.
Yo u can switch o. theve hicle at any time as fol-
lo ws:
R Viath e Smartphone App
R By pressing theÜ orß button on the
key
% Further information can be found in the
smartphone app.
Secur
Secur ing t
ing the v
he v ehicle ag
ehicle ag ains
ainst st
t star
arting bef
ting bef or
ore car ry-
e car ry-
ing out maint
ing out maint enance or r
enance or repair w
epair wor
ork:
k: #
Switch on the hazard warning light system.
or #
Unlock the doors.
or #
Open a side window or the sliding sunroof. R
R
unning-in not
unning-in not es
es To
preser vethe engine during the /rst 1,500 km:
R Drive at varying road speeds and engine
speeds.
R Do not drive at speeds greater than
140 km/h.
R Drive theve hicle in drive prog ram A
or ;.
R ShiT tothe next highest gear at theve ry latest
when the needle reaches the last third before
th ere d area in there v counter.
R Do not shiT down manual lyin order tobrake.
R Avoid overstraining theve hicle, e.g. driving at
full thro ttle.
R V
V ehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: do not
depress the accelerator pedal be yond the
pressure point (kickdown). R
Only increase the engine speed gradually and
accelerate theve hicle tofull speed aTer
1,500 km.
This also applies when the engine or parts of the
driv etra in ha vebeen replaced.
Please also obser vethefo llowing running-in
no tes:
R In cer tain driving and driving saf ety sy stems,
th e sensors adjust automatically while a cer-
ta in distance is being driven aTer theve hicle
has been deli vered or aTer repairs. Full sys-
te m e.ectiveness is not reached until the end
of this teach-in process.
R Brakepads, brake disks and tyres that are
either new or ha vebeen replaced only achie ve
optimum braking e.ect and grip aTer se veral
hund red kilometres of driving. Compensate for
th ere duced braking e.ect byapplying greater
fo rc eto the brake pedal. 172
172
Driving and parking

N
N
o
ot
tes on dr
es on dr iving
iving &
W
W ARNING
ARNING Risk of accident due toobjects
in the driver's foot we ll
Objects in the driver's foot we ll may impede
pedal tr avel or block a depressed pedal.
This jeopardises the operating and road saf ety
of theve hicle. #
Stow all objects in theve hicle securely
so that they cannot getinto the driver's
fo ot we ll. #
Always /t the 0oor mats securely and as
prescribed in order toensure that there
is alw ays su1cient room forth e pedals. #
Do not use loose 0oor mats and do not
place 0oor mats on top of one ano ther. &
W
W ARNING
ARNING Risk of accident due toincor-
re ct foot we ar
Incor rect foot we ar includes, forex ample:
R shoes with plat form soles R
shoes with high heels
R slippers
There is a risk of an accident. #
Alwayswe ar suitable foot we ar so that
yo u can operate the pedals safel y. &
W
WARNI NG
ARNI NGRisk of accident if theve hicle is
switched o. while driving
If yo u switch o. theve hicle while driving,
saf ety functions are restric ted or no longer
av ailable.
This may a.ect the po wer steering system and
th e brake forc e boosting, forex ample.
Yo u will need touse considerably more force
to steer and brake, forex ample. #
Do not switch o. theve hicle while driv-
ing. &
D
DAN
AN GER
GER Risk of fatal injuries caused by
ex haust gases
Combustion engines emit poisonous exhaust
ga ses such as carbon monoxide. Inhaling
th ese exhaust gases is hazardous tohealth
and leads topoisoning. #
Never lea vetheve hicle or, if present, the
stationa ryheater running in an enclosed
space without su1cient ventilation. &
W
WARNI NG
ARNI NGRisk of skidding and of an acci-
dent due toshiTing down on slippery road
sur faces
If yo u shiT down on slippery road sur faces to
increase the engine braking e.ect, the drive
wheels may lose traction. #
Do not shiT down on slippery road sur fa-
ces toincrease the engine braking
e.ect. Driving and parking
173
173

&
D
DAN
AN GER
GER Risk of fatal injury due topoison-
ous exhaust gases
If th eta ilpipe is bloc ked or su1cient ventila-
tion is not possible, poisonous exhaust gases
such as carbon monoxide may enter theve hi-
cle. This is the case if theve hicle gets stuck in
sno w,forex ample. #
Keep theta ilpipe and the area around
th eve hicle free from snow when the
ve hicle or the stationary heater is run-
ning. #
Open a wind owonthe side of theve hicle
fa cing away from the wind toensure an
adequate supply of fresh air. &
W
WARNING
ARNING Risk of accident due tothe
brake system overheating
If yo u lea veyour foot on the brake pedal when
driving, the brake system may overheat.
This increases the braking distance and the
brake system can even fail. #
Never use the brake pedal as a foot re st. #
Do not depress the brake pedal and the
accelerator pedal at the same time while
driving. *
N
NOOTE
TE Engine damage due toexcessively
high engine speeds The engine will be damaged if
you drive with
th e engine in theove rrev ving range. #
Do not drive with the engine in theove r-
re vving range. *
N
NOOTE
TE Causing wearto the brake linings by
permanently depressing the brake pedal #
Do not permanently depress the brake
pedal while driving. #
Touse braking e.ect of the engine, shiT
to a lo werge ar in good time. *
N
NOOTE
TE Damage tothe driv etra in and
engine when pulling away #
Do not warm upthe engine while the
ve hicle is stationar y.Pull away immedi-
atel y. #
Avoid high engine speeds and driving at
full thro ttle until the engine has reached
its operating temp erature. *
N
NOOTE
TE Damage tothe catalytic con verter
due tonon-combusted fuel The engine is not
running smoo thly and is mis-
/ring.
Non-combus ted fuel may getinto the catalytic
con verter. #
Only depress the accelerator pedal
slightl y. #
Have the cause recti/ed immediately at
a qu ali/ed specialist workshop. 174 174
Driving and parking

*
N
N O
OTE
TE Reduced battery life due tofrequent
short-distance trips The 12 V battery may not be su1cien
tly
ch arge d when theve hicle is used only for
short-dis tance trips. This reduces the life of
th e batter y. #
Drive longer distances regula rly to
ch arge the batter y. *
N
N O
OTE
TE Damage totheve hicle due tonot
observing the maximum permitted head-
ro om clearance If
th eve hicle height is greater than the maxi-
mum permitted headroom clearance, thero of
and other parts of theve hicle may be dam-
aged. #
Obser vethe signposted headroom clear-
ance. #
Ifth eve hicle height is greater than the
permitted headroom clearance, do not
enter. #
Obser vethech anged vehicle height with
add-on roof equipment. N No
ot
tes on dr
es on dr iving wit
iving with a r
h a roof load, tr
oof load, tr ailer or fully
ailer or fully
laden v
laden v ehicle
ehicle
When driving with a loaded roof luggage rack or
trailer as well as with a fully laden or fully occu-
pied vehicle, theve hicle's driving and steering
ch aracteristics change.
Yo u should bear thefo llowing in mind:
R Do not exceed the permissible roof load and
to wing capacity. Also obser vethete ch nical
data in the printed Owner's Manual.
R Evenly distribute thero of load, and place
heavy objects at the bottom. Also comply with
th e no tes on loading theve hicle
(/ page 118).
R Drive attentivel y,and avoid suddenly pulling
awa y,braking and steering as well as rapid
cornering.
Not
Not es on dr
es on dr iving on salt-tr
iving on salt-tr eat
eated r
ed r oads
oads
The braking e.ect is limited on salt-treated roads. Therefore, obser
vethefo llowing no tes:
R due tosalt build-up on the brake disks and
brakepads, the braking distance can increase
considerably or result in braking only on one
side
R maintain a much greater safe distance tothe
ve hicle in front
To remo vesalt build-up:
R brake occasionally while paying attention to
th e tra1c conditions
R carefully depress the brake pedal at the end of
th e journey and when starting the next jour-
ney
N
No ot
tes on aq
es on aq uaplaning
uaplaning
Aq uaplaning can take place once a cer tain
amount of water has accumulate d onthero ad
sur face.
Obser vethefo llowing no tes during heavy precipi-
ta tion or in conditions in whi chaquaplaning may
occur:
R reduce speed
R avoid tyre ruts Driving and parking
175
175

R
avoid sudden steering mo vements
R brake careful ly
% Also obser vethe no tes on regula rly ch ecking
wheels and tyres (/ page 374).
N
No ot
tes on dr
es on dr iving t
iving thr
hrough w
ough w at
ater on t
er on t he r
he r oad sur-
oad sur-
f
f ace
ace
Wa ter which has entered into theve hicle can
damage the engine, electrics and transmission.
Wa ter can also enter the air intake of the engine
and cause engine damage.
Obser vethefo llowing if you must drive thro ugh
wa ter:
R The water,when calm, may only reach the
lo we r edge of theve hicle body.
R Drive at a maximum speed of 10 km/h; water
can otherwise enter theve hicle interior or
engine compartment.
R Vehicles tr avelling in front, or oncoming vehi-
cles, can create waves which may exceed the
maximum permissible dep thofthewa ter.
The braking e.ect of the brakes is reduced aTer
fo rd ing. Brake carefully while paying attention toth
e tra1c conditions until braking po wer has been
fully restored. EC
EC
O st
O st ar
art/st
t/st op function
op function EC
EC
O st
O st ar
art/st
t/st op function
op function
% The ECO start/stop function is not available
in all drive prog rams, depending on the
engine. Obser vethe status display in the
inst rument display forth is.
If all vehicle- related conditions for an automatic
engine stop are met, the engine is switched o.
automaticall y:
R V
V ehicles wit
ehicles wit h manual tr
h manual tr ansmission:
ansmission: You brake
th eve hicle, shiT into neutral 005Cwhen tr avel-
ling at a low speed and then release the clutch
pedal.
R V
V ehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: Yo u
brake theve hicle toa standstill in transmis-
sion position 005Bor005C.
R You activate the HOLD function or engage
transmission position 005D. %
Ifth e system de tects an intelligent stop inhibi-
to r,fo rex ample, a stop sign, the engine will
not stop.
If yo u activate the HOLD function or engage
th e park position 005D,the engine can be
switched o. in spite of an intelligent stop
inhibitor.
% In transmission position 005E,the engine is not
switched o. automatically even when the
HOLD function is switched on.
The engine restarts au tomatically in thefo llowing
cases:
R V
V ehicles wit ehicles wit h manual tr
h manual tr ansmission:
ansmission: Yo u
depress the clutch pedal.
R V
Vehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: Yo u
shiT into transmission position 005Bor005E.
R You depress the accelerator pedal.
R An automatic vehicle engine start is requ ired.
St atus displ ayinthe inst rument displa y:
R The symbol 00D6(gre en) appears when the
ve hicle is at a standstill: The engine was
switched o. bythe ECO start/s top function. 176
176
Driving and parking

R
The symbol 00D5(yellow) appears when the
ve hicle is at a standstill: Not all vehicle condi-
tions for an engine stop ha vebeen met.
R Neither the symbol 00D6nor00D5 appears
when theve hicle is at a standstill: An intelli-
ge nt stop inhibitor was de tected, e.g. a stop
sign.
R The symbol sappears: The ECO start/
stop function is deactivated or there is a mal-
function.
If th e engine was switched o. bythe ECO start/
stop function and you lea vetheve hicle, a warning
to ne sounds and the engine is not restar ted. In
addition, the display message Vehicle is opera-
tional Switch off ignition before exiting appears
in the inst rument displa y.Ifyo u do not switch o.
th eve hicle, it is automatically switched o. aTer
th re e minutes. Deactiv
Deactiv ating or activ
ating or activ ating t
ating the EC
he ECO st
O star
art/st
t/st op
op
function
function #
Press button 1.
A display appears in the inst rument clus ter
when switching the ECO start/s top function
o./on.
% A continuous sdisplay appears in the
inst rument cluster while the ECO start/s top
function is deactivated. EC
EC
O displa
O displa y function
y function The ECO display summarises
your driving charac-
te ristics from the start of the journey toits com-
pletion and assists you in achieving the most eco-
nomical driving style.
Yo u can in0uence consum ption bydoing thefo l-
lowing:
R driving with particular care.
R V
V ehicles wit ehicles wit h aut
h aut omatic tr
omatic tr ansmission:
ansmission: driving
in drive prog ram ;.
R V Vehicles wit ehicles wit h manual tr
h manual tr ansmission:
ansmission: driving in
drive prog ram A.
R following thege arshiT recommendations. Driving and parking
177
177