engine MERCEDES-BENZ B-CLASS HATCHBACK 2021 User Guide

R
The seat backrest will not be able restrain
objects or goods in the load compartment.
Alw ays ensu rethat the seat and seat backrest
are engaged, in particular:
R Before persons tr avel in theve hicle while
sitting on a seat with the easy entry and
ex itfeature
R ATer the seat has been adjusted.
R ATer the easy entry and exitfeature has
been used
R ATer the load compartment enlar gement
has been folded forw ards &
W
WARNING
ARNING Risk of injury from adjusting
th ere ar seats while driving
Yo u or other vehicle occupants could be trap-
ped and thereby injured. #
Adjust there ar seats before starting the
engine. *
N
NOOTE
TE Damage caused byobjects in the
fo ot we ll or behind there ar seats When adjusting
thefo re -and-aT position, the
re ar seats and/or the object can be damaged. #
Stow objects in a suitable place. This function is
available only forve hicles with a
mo vable rear ben chseat.
The components of there ar ben chseat can be
mo ved. You can mo vetheright-hand and leT-hand
parts toget her with the centre part independent ly
of each other. #
LiT release handle 1and slide the cor re-
sponding part of the bench seat into the
desired position. #
Let go of release handle 1. #
Make sure that the seat is engaged. 110
110
Seats and st
owing

Oper
Oper
ating t
ating t he memor
he memor y function
y function S S
t tor
or ing
ing #
Set the desired position for all systems. #
Brie0y press memory button Vandthen
press preset position 0037,TorU
within thre e seconds. #
T
T o call up:
o call up: press and brie0y hold one of preset
position buttons 0037,TorU.
ATer releasing the button, all systems are
mo ved into the stored position. S
S
t
to
o w
w ag
ag e ar
e ar eas
eas N
No
ot
tes on loading t
es on loading t he v
he vehicle
ehicle &
D
DAN
AN GER
GER Risk of poisoning from exhaust
ga ses
Combustion engines emit poisonous exhaust
ga ses, such as carbon monoxide. Exhaust
ga ses can enter theve hicle interior if theta il-
ga te is open when theve hicle is running,
especially if theve hicle is in motion. #
Always switch o. theve hicle before
opening theta ilgate. #
Never drive with theta ilgate open. &
W
WARNING
ARNING Risk of injury from unsecured
items in theve hicle
If objects, lug gage or loads are not secured or
not secured su1cient ly,they could slip, tip
ov er or be thro wn around and thereby hit vehi-
cle occupants.
There is a risk of injur y,particular lyin the
eve nt of sudden braking or a sudden change
in direction. #
Always st owobjects in such a wayth at
th ey cannot be thro wn around. #
Before the journe y,secure objects, lug-
ga ge or loads against slipping or tipping
ove r. &
W WARNI NG
ARNI NGRisk of injury due toobjects
being st owed incor rectly
If objects in theve hicle interior are st owed
incor rectl y,they can slide or be thro wn around
and hit vehicle occupants. In addition, cup
holders, open st owage spaces and mobile
phone brac kets cannot alw aysreta in all
objects they contain. 118
118
Seats and st
owing

If
th e battery is insu1cient lych arge d, the stand-
ing lights or parking lights will be switched o.
automatically tofacilitate the next engine start.
The exterior lighting (e xcept standing and parking
lights) will switch o. automatically when the driv-
er's door is opened.
R Obser vethe no tes on sur round lighting
(/ page 146).
A
A ut
ut omatic dr
omatic dr iving lights function
iving lights function
When theve hicle is switched on, the standing
lights, low beam and daytime running lights are
switched on automatically depending on the light
conditions. &
W
WARNING
ARNING Risk of accident when the
dipped beam is switched o. in poor visi-
bility
When the light switch is set to0058 ,the
dipped beam may not be switched on auto-
matically if there is fog, snow or other causes
of poor visibility such as spr ay.#
In such cases, turn the light switch to
0058 . The automatic driving lights are only an aid.
Yo u
are responsible forve hicle lighting.
Switc Switc hing t
hing t he r
he rear f
ear f og lights on or
og lights on or o.
o.
R
R eq
eq uir
uir ements:
ements:
R The light switch is in the0058 or0058 posi-
tion. #
Press the 005E button.
Please obser vethe count ry-speci/c la wsonthe
use of rear fog lamps.
R
R egulating headlam
egulating headlam p r
p rang
ang e (halog
e (halog en headlam
en headlam ps)
ps)
The headla mprange adjuster all owsyo uto adjust
th e cone of light from the headlamps in relation to
th eve hicle's load condition. 005A
Driver's seat and front passen ger seat occu-
pied
0047 Driver's seat, front passenger seat and rear
seats occupied
0048 Driver's seat, front passen ger seat and rear
seats occupied, load compartment laden
0049 Driver's seat and front passen ger seat occu-
pied and maximum permissible rear axle load
utilised Light and sight
139
139

Ad
aptive Highbeam Assist Plus automatically
switches between thefo llowing types of light:
R Low beam
R Partial high beam
R High beam
Pa rtial high beam uses the high beam toshine
past other road users rather than dazzling them. The
vehicle in front will be illuminated bythe low
beam.
At speeds greater than 30 km/h:
R If no other road users are de tected, the high
beam will switch on automaticall y.
R Ifot her road users are de tected, the partial
high beam will switch on automaticall y.
At speeds below 25 km/h or when there is su1-
cient street lighting:
R The high beam will switch o. automaticall y.
R The partial high beam will switch o. automati-
cally.
% The system's optical sensor is located behind
th e windscreen near theove rhead control
panel.
Switc
Switc hing A hing A dap
daptiv
tive Highbeam Assis
e Highbeam Assist Plus t Pluson/o.
on/o.
Switc
Switc hing on
hing on #
Turn the light switch tothe0058 position. #
Switch on the high beam using the combina-
tion switch.
When the high beam is switched on automati-
cally in the dar k, the00CE indicator lamp will
light up on the central display section of the
inst rument displa y.
Switc
Switc hing hingo.
o. #
Switch o. the high beam using the combina-
tion switch. Se
Se
tting t
tting t he e
he ext
xter
er ior lighting
ior lighting switc
switch-o.
h-o. dela
dela y time
y time R
R
eq
eq uir
uir ements:
ements:
R The light switch is in the0058 position.
Multimedia system: 4 © 5
Settings 5
Lights
5 Ext. light. del. sw. off #
Set the swit ch-o. delay time.
When theve hicle engine is switched o., the
ex terior lighting will be activated forth e set
time. Light and sight
145
145

Se
Se
tting t
tting t he air dis
he air distr tribution
ibution Multimedia system:
4 Climate menu #
Call up the air conditioning menu
(/ page 158). #
Select a row of seats. #
T
To se
o se t t
t the air dis
he air dis tr
tribution:
ibution: select0061,009C
or 009B. #
Set the air0o w.
% Several air distribution options can be selec-
te d at the same time, forex ample toset the
climate cont rolfo rth e windscreen and the
fo ot we lls simultaneousl y.
The 0061 climatecont rolfo rth e windscreen
can only be selected forth e /rst seat row. Switc
Switc
hing t
hing t he sync
he sync hr
hronisation functiononisation function on/o.
on/o. via
via
t
t he air conditioning contr
he air conditioning contr ol panel
ol panelClimate control can be set centrally using
the syn-
ch ronisation function. The temp erature and air
distribution settings forth e driver's side will be adop
ted automatically forth e front passenger
side. #
Press the0 button.
The synchronisation function will be deactivated if
th e settings for one of theot her climate zones are
ch anged. Switc
Switc
hing t
hing t he sync
he sync hr
hronisation function
onisation function on/o.
on/o.via
via
t
t he multimedia syst
he multimedia syst em
em Multimedia system:
4 Climate menu 5
First row of seats
Climate cont rol can be set centrally using the syn-
ch ronisation function. The driver's settings for
te mp erature, air quantity and air distribution are
adop ted automatically for all climate zones. #
Select SYNCand switch on or o.. Demis
Demisting t
ting the windo ws
he wind ows W
W
indow
indow s mist
s mist ed up on t
ed up on t he inside
he inside #
Press the0058 button. #
Ifth e windo wscontinue tomist up: press the
0064 button.
W
W indow
indow s mist
s mist ed up on t
ed up on t he outside
he outside #
Switch on the windscreen wipers. #
Press the0058 button. Switc
Switc
hing air
hing air -r
-r ecir
ecir culation mode
culation mode on/o.
on/o. #
Press the0072 button.
The interior air will be recirculated.
Air-recirculation mode automatical lyswitches to
fresh air mode aTer a while.
% If air-re circulation mode is switched on, the
wind ows may mist up more quickl y.Switch on
ai r-re circulation mode only brie0y. Switc Switc
hing r
hing r esidual heat
esidual heat on/o.
on/o. R
R
eq
eq uir
uir ements:
ements:
R theve hicle is par ked.
% Only vehicles with a diesel engine can use
re sidual heat. Climate cont
rol
159
159

It is possible
tomake use of there sidual heat
from the engine tocontinue heating or ventilating
th e front compartment of theve hicle for appr ox-
imately 30 minutes, depending on thete mp era-
ture set. #
T To activ o activ at
ate:
e: press the 0056 button.
Re sidual heat will be switched o. automaticall y.Pr
Pr
e-entr
e-entr y climat
y climat e contr
e control using t
ol using t hekey
he key F
F
unction of pr
unction of pr e-entr
e-entry climat
y climat e contr
e control using t
ol using t he
he
key
key
Before entering theve hicle, the driver's seat area
or the whole vehicle interior can be brie0y pre-
wa rmed or pre-cooled.
When pre-cooling, thefo llowing functions are acti-
va ted as needed:
R Automatic climate control
R Blower
R Seat ventilation
When pre-heating, thefo llowing functions are acti-
va ted as needed:
R Automatic climate control R
Blower
R Seat heater
R Steering wheel heater
R Mirror heater
R Rear wind owheater
Se
Se tting pr tting pr e-entr
e-entry climat
y climat e contr
e control via t
ol via thekey
he key
Multimedia system:
4 Climate menu 5
Pre-entry climate ctrl
Switc
Switc hing
hingon/o.
on/o. #
Select Z. #
Select Pre-entry climate control via key.
Switc Switc hing pr hing pr e-entr
e-entry climat
y climat e contr
e control via t
ol via thekey
he key
on/o.
on/o.
R R eq
eq uir
uir ements:
ements:
R The high-voltage battery is charge d su1-
cient ly.
R The function has been activated via the multi-
media system. #
T
To switc
o switc h on:
h on: unlock theve hicle.
The climate cont rol functions are activated for
up to/ve minutes for pre-heating and pre-
cooling.
Pre-entry climate control via theke y cann otbe
activated more than twice when theve hicle is
switched o.. #
T
To switc
o switc h
h o.:
o.: push the003B button up or
down.
The following functions will remain active once the
ve hicle has been star ted:
R Seat heating
R Seat ventilation 160
160
Climate cont
rol

Dr
Dr
iving
iving N
No
ot
tes on plug-in h
es on plug-in h ybr
ybrids
ids N
No
ot
tes on plug-in h
es on plug-in h ybr
ybrid oper
id oper ation
ation &
W
WARNING
ARNING Risk ofchemical burns and poi-
soning from damaged high-voltage battery
If th e housing of the high-voltage battery has
been damaged, electrolyte and gases may
leak out. #
Avoid contact with the skin, eyes or
clo thing. #
Immediate lyrinse electrolyte splashes
o. with water and seek medical atten-
tion straight away. &
D
DAN
AN GER
GER Risk of explosion from excessive
internal pressure of the high-voltage bat-
te ry
Flammable gas may escape and ignite in the
eve nt of a vehicle /re. #
Stop thech arging process immediately
in case of unusual odours, smoke or
burn mar ks. #
Leavethe danger zone immediatel y.
Secure the danger zone at a su1cient
distance. #
Call the /re brigade. The
hybrid system combines a combustion engine
with an electric mo tor.
Characteristics when theve hicle is at a standstill:
R The combustion engine is generally switched
o..
R Idle speed only occurs in cer tain instances.
Characteristics when starting theve hicle:
R Ifth e high-voltage battery is su1ciently
ch arge d, theve hicle can be star ted with the
electric drive without the combustion engine
(noiseless start).
R Ifth e high-voltage battery forth e electrical
drive is not su1ciently charge d or the operat-
ing temp erature of the combustion engine has not been
reached, theve hicle can start with
th e combustion engine.
% Depending on the system, it may happen that
ev en though the high-voltage battery is
ch arge d, electric mode has restric ted or no
av ailabilit y.Once the combustion engine has
been operated for long enough, electric mode
is again available without restriction.
% Tostart the combustion engine, the high-volt-
age battery can be used as a star ter batter y.
Characteristics with moderate po wer output
re qu ests:
R The combustion engine is switched o. as
oTen as possible during the journe y.
R The vehicle can, depending on the drive pro-
gr am selected and the battery charge leve l, be
accelerated electrically up tospeeds of about
140 km/h.
Characteristics with high po wer output requ ests:
R The electric mo tor supports the combustion
engine (boost e.ect), e.g. when pulling away
or accelerating.
R The high-voltage battery is discharging. 166 166
Driving and parking

Characteristics when
releasing the accelerator
pedal during the journe y:
R The electric mo tor is operated as a alternator
when in overrun mode and during braking.
R The high-voltage bat tery isch arging.
No tes on elect ric mode:
R Vehicles with hybrid systems generate signi/-
cant lyless noise when stationary and when
being driven than vehicles with combustion
engines.
R When driving in elect ric mode, theve hicle may
not be heard by otherroad users due tothe
signi/cantly reduced noise generated.
It is forth is reason that theve hicle is equip-
ped with a sound generator, which ser ves as
an acoustic vehicle warning system (A VAS).
R If not all of theve hicle conditions for electric
mode are met, then the combustion engine is
switched on.
% V
V ehicles wit
ehicles wit h diesel par
h diesel par ticulat
ticulate
e/lt
/lt er
ers:
s: During
th ere ge neration of the diesel particulate /l-
te r,th e drive prog rammes are not available or are
restric ted and the battery charge level
may change.
No tes on the acoustic vehicle warning system:
R The sound generator generates speed-depend-
ent vehicle noise emissions when driving
fo rw ard or backing up at a speed of up to
around 30 km/h.
R This helps other road users, particular ly
pedest rians and cyclists, tohear your vehicle
better.
R When driving at speeds abo ve20 km/h The
ve hicle acoustic warning system gradually
switches o..
R The sound generator is o. when theve hicle is
stationar y. Manual disconnection of t Manual disconnection of t
he high-v he high-volt
oltag
age on-
e on-
boar
boar d electr
d electr ical syst
ical syst em
em &
D
DAN
AN GER
GER Risk of dea thand /re due to
modi/ed and/or damaged components of
th e high-voltage on-board electrical sys-
tem
The vehicle's high- voltage on-board electrical
system is under high voltage. If you modify
component parts in theve hicle's high- voltage
on-board electrical system or touch damaged
component parts, you may be electrocuted. In
addition, modi/ed and/or damaged compo-
nents may cause a /re.
In theev ent of an accident or impact tothe
ve hicle underbod y,components of the high-
vo ltage electrical system may be damaged
although the damage is not visible. #
Never make any modi/cations tothe
high- voltage on-board electrical system. #
Do not switch on or use theve hicle if its
high- voltage on-board electrical system
components ha vebeen modi/ed or dam-
aged. Driving and parking
167 167

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