2021 MERCEDES-BENZ B-CLASS HATCHBACK battery

Changing bulbs (only
forve hicles with hal-
ogen headlamps) ......................................... 147
Wi ndsc reen wipers and windscreen
wa sher system ............................................ 149
Mir rors ........................................................ 153 Climat
Climat
e contr
e control ol........................................... 157 157
Overview of climate control systems ............ 157
Operating the climate control system .......... 158 Dr
Dr
iving and par
iving and par king
king..................................... 166 166
Driving ........................................................1 66
DY NAMIC SELECT switch ........................... .182
Manual transmission ................................... 185
Au tomatic transmission .............................. .187
Fu nction of the 4MATIC ...............................1 91
Re fuelling .................................................... 191
Charging the high-voltage battery (plug-in
hy brid) ........................................................ 198
Pa rking .......................................................2 15
Driving and driving saf ety sy stems ............... 223
Tr ailer hitch ................................................ .273
Bicycle rack function ................................... 277
Ve hicle towing instructions .......................... 279 Ins
Ins
tr
trument displa
ument displa y and on-boar
y and on-boar d com-
d com-
put
put er
er........................................................... 280 280
No tes on the inst rument display and on-
board computer .......................................... 280
Overview of instrument display .................... 281
Overview of buttons on the steering wheel ... 282
Operating the on-board computer ................2 82
Fu nction of the po wer me ter (plug-in
hy brid) ........................................................ 284
Fu nction of the electric mo tor po wer
av ailability displ ay(plug-in hybrid) ................ 284
Displaying the po wer me ter (plug-in
hy brid) ........................................................ 285
Overview of displa ysinthe inst rument
display ........................................................ 285
Head-up display .......................................... 285 MBUX multimedia syst MBUX multimedia syst
em
em........................... .288
288
Overview and operation ............................... 288
System settings .......................................... 297
Plug-in hybrid settings ................................ .301
Na vigation .................................................. .302
Te lephone ................................................... 311
Mercedes me app ....................................... 314 Mercedes-Benz emer
gency call system ....... 323
Ra dio & media ............................................ .330
Sound settings ............................................ 335 Maint Maint
enance and car
enance and car e
e................................. 336 336
ASS YST PLUS service inter val display .......... 336
Engine compartment ................................... 337
Cleaning and care ....................................... 343 Br Br
eakdo
eakdo wn assist
wn assist ance
ance................................. 352 352
Emer gency .................................................. 352
Flat tyre ...................................................... 354
Battery (vehicle) .......................................... 361
To w- starting or towing away ........................ 365
Electrical fuses ............................................ 371 Wheels and tyr Wheels and tyr
es
es......................................... 374 374
No tes on noise or unusual handling char-
acteristics ................................................... 374
No tes on regula rly inspecting wheels and
tyres .......................................................... .374
No tes on snow chains ................................. 374
Ty re pressure .............................................. 375 Contents
3 3

Pr
ot
Pr otection of t
ection of t he en
he envir
vironment
onment
+ ENVIR
ENVIR
ONMENT
ONMENT AL NO
AL NOTE
TE Environmental
damage due tooperating conditions and
personal driving st yleThe pollutant emission of
theve hicle is
directly related tothewa yyo u operate the
ve hicle.
Operate your vehicle in an environmentally
re sponsible manner tohelp pr otect the envi-
ro nment. Please obser vethefo llowing recom-
mendations on operating conditions and per-
sonal driving st yle.
Oper
Oper ating conditions:
ating conditions: #
Make sure that the tyre pressure is cor-
re ct. #
Do not car ryany unnecessary weight
(e.g. roof luggage rack s once you no lon-
ge r need them). #
Adhere tothe service inter vals.
A regula rly serviced vehicle will cont rib-
ute toenvironmental pr otection. #
Always ha vemaintenance workcar ried
out at a quali/ed specialist workshop.
P
P er
er sonal dr
sonal dr iving s
iving stytyle:
le: #
Do not depress the accelerator pedal
when starting the engine. #
Do not warm uptheve hicle while sta-
tionar y. #
Drive carefully and maintain a suitable
distance from theve hicle in front. #
Avoid frequent, sudden acceleration and
braking. #
Change gear in good time and use each
ge ar only up to00C3 of its maximum
engine speed. #
Switch o. theve hicle in stationary traf-
fi c, e.g. byusing the ECO start/s top
function. #
Drive in a fuel-e1cient manner. Obse rve
th e ECO display for an economical driv-
ing style. Plug-in h Plug-in h
ybr
ybrid
id
+ ENVIR
ENVIR
ONMENT
ONMENT AL NO
AL NOTE
TEEnvironmental
pollution caused byirre sponsible disposal
of the high-voltage battery A high-voltage battery contains materials
which are harmful
tothe environment. #
Dispose of faulty high-voltage batteries
at a quali/ed specialist workshop. T T
ak
ak e-bac
e-bac k of end-of-lif
k of end-of-lif e v
e vehicles
ehicles
EU countr EU countr ies only:
ies onl y:
Mercedes-Benz will take back your end-of-life
ve hicle for environment-fri endly disposal in
accordance with the European Union (EU) End-of-
Life Vehicles Directi ve.
A network of vehicle take -back points and dis-
mantlers has been established foryo uto return
yo ur vehicle. You can lea veit at any of these
points free of charge . This makes an impor tant
cont ribution toclosing there cycling circle and
conserving resources. 24 24
Gene
ral no tes

#
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. *
N
NO OTE
TE Battery discharging from using devi-
ces connected tothe diagnostics connec-
tion Using devices at
the diagnostics connection
drains the batter y. #
Check thech arge leve l of the batter y. #
Ifth ech arge leve l is lo w,charge the bat-
te ry, e.g. bydriving a considerable dis-
ta nce. Please also no
tethe information about the 12 V
battery and short-dis tance trips in the "Driving
and Parking" chap ter (/ page 173). Connecting and using ano
ther device with the
diagnostics connection can ha vethefo llowing
e.ects:
R Malfunctions in theve hicle system
R Perm anent damage tovehicle components
Please referto thewa rranty term s and conditions
fo rth is matter. Moreo
ver,connecting equipment tothe diagnos-
tics connection can lead toemissions monitoring
information being reset, forex ample. This may
lead totheve hicle failing tomeet there qu ire-
ments of the next emissions inspection during the
main inspection. Quali/ed
Quali/ed
specialis
specialist w
t work
ork shop
shop
A qu ali/ed specialist workshop has the necessary
special skills, tools and quali/cations tocor rectly
car ryout any necessary workon your vehicle.
This particular lyapplies tosaf ety-re leva nt wo rks.
Alw ays ha vethefo llowing workcar ried out on
yo ur vehicle at a quali/ed specialist workshop:
R Safety-re leva nt wo rks
R Service and maintenance work
R Repair work
R Modi/cations as well as installations and con-
ve rsions
R Workon electronic components
R Plug-in h
Plug-in h ybr
ybrid:
id:workon thehy brid system General no
tes
39
39

ing state, component loads, maintenance
requ ire-
ments and tech nical events or faults.
Depending on theve hicle equipment, thefo llo w-
ing data are stored:
R operating status of system components, such
as /ll le vels, tyre pressure or battery status
R malfunctions or faults in impor tant system
components, such as lights or brakes
R system reactions in special driving situations,
such as airbag depl oyment or the inter vention
of stability cont rol systems
R information on events leading tovehicle dam-
age
In cer tain cases, it may be requ ired tostore da ta
th at wo uld ha veotherwise been used only temp o-
rari ly. This may be the case if theve hicle has
de tected a malfunction, forex ample.
If yo u use services, such as repair services and
maintenance work, stored operational data as
we ll as theve hicle identi/cation number can be
re ad out and used. They can be read out by
service network emplo yees, such as workshops
and manu facturers or third parties, such as break- down services. The same is true in
the case of
wa rranty claims and quality assurance measures.
In general, there adout is per form ed via the legally
prescribed port forth e diagnostics connection in
th eve hicle. The operational data that are read out
document tech nical states of theve hicle or of
individual components and assist in the diagnosis
of malfunctions, compliance with warranty obli ga-
tions and quality impr ovement. Tothat end, these
data, in particular information about component
loads, tech nical events, malfunctions and other
fa ults may be transmitted along with theve hicle
identi/cation number tothe manufacturer. Fur-
th ermore, the manufacturer is subject toproduct
liability. Forth is reason the manufacturer also
uses operational data from theve hicle, forex am-
ple, forre calls. These data can also be used to
ex amine the customer's warranty and guarantee
claims.
Fa ult memories in theve hicle can be reset by a
service outl etor at your requ est as part of repair
or maintenance work. Conv
Conv enience and inf ot
enience and inf otainment functions ainment functions
Yo u can store con venience settings and individual
settings in theve hicle and change or reset them
at any time.
Depending on theve hicle equipment, this
includes thefo llowing settings, forex ample:
R seat and steering wheel positions
R suspension and climate cont rolsettings
R individual settings, such as interior lighting
Depending on the selected equipment, you can
import data into vehicle inf otainment functions
yo urself.
Depending on theve hicle equipment, this
includes thefo llowing data, forex ample:
R multimedia data, such as music, /lms or pho-
tosfo r playback in an integ rated multimedia
system
R address book data for use in connection with
an integ rated hands-free system or an integ ra-
te d navigation system
R entered navigation destinations
R data about the use of Internet services General no
tes
43 43

K
K
e
ey
y Ov
Ov
er
ervie
vie w of ke
w of key functions
y functions &
W
W ARNING
ARNING Risk of accident and inju rydue
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.
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. *
N
NOOTE
TE Damage totheke y caused bymag-
netic /elds #
Keep theke yaw ay from strong magnetic
/elds. Ve
hicle key
1 Locks
2 Indicator lamp 3
Unloc ks
4 Opens/closes theta ilgate
% If indicator lamp 2does not light up aTer
pressing theÜ orß button, the battery
is we ak or possibly dischar ged. Re place the
battery as soon as possible.
Re place theke y battery (/ page 83).
The key loc ksand unloc ksthefo llowing compo-
nents:
R Doors
R Fuel /ller 0ap
R Soc ket 0ap (plug-in hybrid)
R Tailgate
If th eve hicle is not opened within appr oximately
40 seconds aTer unlocking, it loc ksagain. Anti-
th eT pr otection is primed again.
Do not keep theke yto get her with elect ronic devi-
ces or me tal objects. This can a.ect theke y's
functionalit y. Opening and closing
81 81

R
R
emo
emo ving/inser
ving/inser ting t
ting the emerg
he emerg encykey
ency key R R
emo emo ving t
ving t he emerg
he emerg encykey
ency key #
Press release button 1.
Emer gency key2 is pushed out slightl y.#
Pull out eme rgency key2 until it en gage s in
th e intermediate position. #
Press release button 1again and fully
re mo veemer gency key2.
Inser
Inser ting t
ting t he emerg
he emerg encykey
ency key #
Press release button 1. #
Insert emer gency key2 tothe intermediate
position or fully until it engages. %
You can use the intermediate position of
emer gency key2 toattach theke yto akey
ri ng. R
R
eplacing t
eplacing t heke
he key batt
y batt ery
ery &
D
DAN
AN GER
GER Risk of fatal injuries due toswal-
lowing batteries
Bat teries contain toxic and cor rosive subs tan-
ces. Swall owing batteries may cause se vere
internal burns tooccur within two hours.
There is a risk of fatal injur y. #
Keep batteries out of there ach of chil-
dren. #
Ifth e cap and/or the battery compart-
ment does not close securel y,do not use
th eke y any lon ger and keep it out of the
re ach of children. #
If batteries are swallo wed, seek medical
attention immediatel y. +
ENVIR
ENVIR ONMENT
ONMENT AL NO
AL NOTE
TEEnvironmen tal
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. R
R
eq
eq uir
uir ements:
ements:
R Youre qu ire a CR 2032 3 V cell batter y.
Mercedes-Benz recommends that you ha vethe
battery replaced at a quali/ed specialist work-
shop. #
Remo vethe emer gency key (/ page 83). Opening and closing
83
83

#
Press release knob 2down fully and slide
co ver1 inthe direction of the ar row. #
Fold out co ver1 inthe direction of the ar row
and remo ve. #
Remo vebattery compartment 3and take
out the dischar ged batter y. #
Insert the new battery into battery compart-
ment 3. Obser vethe positive pole marking in
th e battery compartment and on the battery
when doing this. #
Push in battery compartment 3.#
Re-attach co ver1 and push it until it
engages. Pr
Pr
oblems wit
oblems wit h t
h the key
he key , tr
, troubleshoo
oubleshoo ting
ting Y Y
ou can no long ou can no long er loc
er lock or unloc
k or unloc k t
k the v
he v ehicle
ehicle
Po ssible causes:
R The key battery is weak or dischar ged. #
Check the battery using the indicator lamp
(/ page 81). #
Replace theke y batter y,if necessary
(/ page 83). #
Use there placement key. #
Use the emer gency keyto lock or unlock
(/ page 88). #
Have theke ych ecked at a quali/ed specialist
wo rkshop.
Ther
Ther e is int
e is int erf
erfer
erence fr
ence fr om a pow
om a pow er
erful r
ful r adio signal
adio signal
sour sour ce ce
Po ssible causes if the function of theke y is
impaired:
R high voltage po wer lines
R mobile phones
R electronic devices (no tebooks, tablets) R
shielding due tome tal objects or induction
loops for electrical gate systems or automatic
bar riers #
Make sure that there is su1cient distance
between theke y and the po tential sou rce of
inter fere nce.
Y
Y ou hav
ou hav e los
e lost a key
t a key #
Have theke y deactivated at a quali/ed spe-
cialist workshop. #
If necessar y,ha ve the mechanical lock
re placed as well. Doors
Doors
N
No
ot
tes on t
es on t he additional door lock
he additional door lock The additional door lock is only
available forve hi-
cles forth e United Kingdom. 84
84
Opening and closing

%
Further information on con venience closing
(/ page 97).
If yo u open theta ilgate from outside, it is auto-
matically unloc ked. Pr
Pr
oblems wit
oblems wit h KEYLESS-GO, tr
h KEYLESS-GO, tr oubleshoo
oubleshooting
ting Y
Y
ou can no long
ou can no long er loc
er lock or unloc
k or unloc k t
k the v
he v ehicle using
ehicle using
KEYLESS-GO
KEYLESS-GO
Po ssible causes:
R The function of theke y has been deactivated.
R The key battery is weak or dischar ged. #
Activate the function of theke y (/ page 82). #
Check the battery using the indicator lamp
(/ page 81). #
Replace theke y batter y,if necessary
(/ page 83). #
Use there placement key. #
Use the emer gency keyto lock or unlock
(/ page 88). #
Have theve hicle and keych ecked at a quali-
/ed specialist workshop. Ther Ther
e is int
e is int erf
erfer
erence fr
ence fr om a pow
om a pow er
erful r
ful r adio signal
adio signal
sour
sour ce
ce
Po ssible causes if the function of KEYLESS-GO is
impaired:
R high voltage po wer lines
R mobile phones
R electronic devices (no tebooks, tablets)
R shielding due tome tal objects or induction
loops for electrical gate systems or automatic
bar riers #
Make sure that there is su1cient distance
between theke y and the po tential sou rce of
inter fere nce. A
A
ctiv
ctiv ating/deactiv
ating/deactiv ating t
ating the aut
he automatic loc
omatic loc king f
king fea-
ea-
ture
ture The
vehicle is loc ked automatically when theve hi-
cle is switched on and the wheels are turning
fa ster than walking pace. #
T To activ o activ at
ate:
e: press and hold button 2for
appr oximately /ve seconds until an acoustic
signal sounds. #
T To deactiv
o deactiv at
ate:
e: press and hold button 1for
appr oximately /ve seconds until an acoustic
signal sounds.
The red indicator lamp on button 2lights up
once theve hicle is loc ked. Opening and closing
87 87