engine MERCEDES-BENZ B-CLASS HATCHBACK 2021 Owners Manual

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences and0050
0050Solutions
Solutions #
Switch o. theve hicle. #
Add 1 l of engine oil (/ page 340). #
Check the engine oil le vel.
No tes on engine oil (/ page 401).
00B3
Engine oil pressure Stop
Switch off engine *T
he oil pressure is too lo w.
* N
NO
OTE
TE Engine damage caused bydriving with insu1cient oil pressure #
Avoid driving with insu1cient oil pressure. #
Stop theve hicle immediately in accordance with the tra1c conditions. Do not continue driving. #
Switch o. theve hicle. #
Consult a quali/ed specialist workshop.
00B3
Engine oil level cannot be
measured *T
he elect rical connection tothe oil le vel sensor has been inter rupted or the oil le vel sensor is faulty. #
Consult a quali/ed speciali stwo rkshop. 478 478
Displ
aymessages and warning/indicator lamps

W
W
ar
ar ning and indicat
ning and indicat or lam
or lamps
ps Ov
Ov
er
ervie
vie w of indicat
w of indicat or and w
or and war
arning lam
ning lam ps
ps Some systems will per
form a self-test when the
ve hicle is switched on. Some indicator and warn-
ing lamps may brie0y light up or 0ash. This beha v-
iour is non-critical. These indicator and warning
lamps indicate a malfunction only if they light up
or 0as haTer theve hicle has been star ted or dur-
ing a journe y.
S
S t
tandar
andar d ins
d instr
trument displ ay
ument display W
W
idescr
idescr een coc
een coc kpit ins
kpit instrtrument display
ument display Depending on
the display setting, the positions of
th e indicator lamps on the inst rument display may
di.er from theex ample shown.
Indicat
Indicat or and w
or and w ar
arning lam
ning lam ps:
ps:
0075 Restraint system (/ page 480)
00E9 Seat belt (/ page 480)
_ Reduced po wer (/ page 482)
00D6 System error (/ page 482)
003D Electricalfault (/ page 482)
ï Trailer hitch (/ page 483)
Ù Powe r steering (/ page 483) ÿ
V
V ehicles wit
ehicles wit h a widescr
h a widescr een coc
een cockpit
kpit:
:
coolant temp erature (/ page 484)
00B9 Engine diagnostics (/ page 484)
0028 V
Vehicles wit
ehicles wit h a diesel engine:
h a diesel engine: preglow
003D Electricalfault (/ page 484)
00D4 Reser vefuel wi thfuel /ller 0ap loca-
tion indicator (/ page 484)
0024 Electric parking brake (red)
(/page 488)
0024 Electric parking brake (yellow)
(/page 488)
004D Brakes (yellow) (/ page 488)
004D Brakes (red) (/ page 488)
L Distancewarning (/ page 490)
Ó Active Brake Assist (/ page 490)
ê Active Brake Assist (/ page 490)
0025 ABS (/page 491)
00E5 ESP®
(/ page 491)
00BB ESP®
OFF (/ page 491) Display messages and
warning/indicator lamps
479 479

W
W
ar
ar ning/indicat
ning/indicat or lampP
or lam pP ossible causes/conseq
ossible causes/consequences and uences and0050
0050Solutions
Solutions
ï
Tr ailer tow hitch warning
lamp *T
hered trailer hitch warning lamp is lit.
The trailer hitch is not operational. &
W
W ARNING
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. #
Notethe messages on the instrument displa y.Engine
Engine
W
W
ar
ar ning/indicat
ning/indicat or lampP
or lam pP ossible causes/conseq
ossible causes/consequences and uences and0050
0050Solutions
Solutions
ÿ
Coolant warning lamp (red) *T
he red coolant warning lamp is lit while the engine is running.
Po ssible causes:
R The temp erature sensor is malfunctioning
R The coolant le vel is too low
R The air supply tothera diator is obstructed
R The radiator fan is faulty 484
484
Display message
s andwarning/indicator lamps

W
W
ar
ar ning/indicat
ning/indicat or lampP
or lam pP ossible causes/conseq
ossible causes/consequences and uences and0050
0050Solutions
Solutions
R The engine coolant pump is faulty
If th ere is an additional warning tone, the coolant temp erature has exceeded 120°C. &
W
WARNING
ARNING Risk of burns when opening the bonnet
If yo u open the bonnet in theeve nt of an overheated engine or /re in the engine compartment, thefo llowing situa-
tions may occur:
R You may come into contact with hot gases.
R You may come into contact with other escaping hot operating 0uids. #
Before opening the bonnet, allow the engine tocool down. #
Intheev ent of a /re in the engine compartment, keep the bonnet closed and call the /re service. #
Stop immediately in accordance with the tra1c conditions and switch o. theve hicle. Do not continue driving. #
Notethe messages on the instrument displa y.
If t If t he coolant t
he coolant t em
em per
per atur
atur e displa
e displa y is at t
y is at the low
he lower end of t
er end of t he t
he tem
emper
per atur
atur e scale:
e scale: #
Consult a quali/ed specialist workshop.
If t
If t he coolant t he coolant t em
emper
per atur
atur e displa
e displa y is at t
y is at the upper end of t
he upper end of t he t
he tem
emper
per atur
atur e scale:
e scale: #
Exit theve hicle and keep a safe distance from it until the engine has cooled down. #
Check the coolant le vel (/ page 342). Display message
s andwarning/indicator lamps
485
485

W
W
ar
ar ning/indicat
ning/indicat or lampP
or lam pP ossible causes/conseq
ossible causes/consequences and uences and0050
0050Solutions
Solutions #
Make sure that the air supply tothera diator is not obstructed. #
Avoiding high loads on the engine, drive tothe nearest quali/ed specialist workshop. In doing so, ensu rethat the
coolant temp erature display remains below 120°C.
ÿ
Coolant warning lamp (yel-
low) *T
he yellow coolant warning lamp is lit while the engine is running.
Po ssible causes:
R The temp erature sensor is malfunctioning
R The charge air, transmission oil or battery cooling is faulty
R The radiator shutters are bloc ked or defective #
Avoiding high loads on the engine, drive tothe nearest quali/ed specialist workshop.
00B9 Engine diagnosis warning
lamp *T
he yellow engine diagnostics warning lamp is lit while the engine is running.
A malfunction has occur red in the engine, theex haust system or the fuel system.
The emissions limit value may ha vebeen exceeded and the engine may be running in eme rgency operation mode. #
Have theve hicle checked as soon as possible at a quali/ed specialist workshop.
V
V ehicles wit
ehicles wit h a diesel engine:
h a diesel engine: the fuel tank may ha vebeen run dr y. #
Start the engine thre eto four times aTer refuelling.
If th eye llow engine diagnosis warning lamp goes out, emer gency ope ration mode is cancelled. The vehicle need not
be checked. 486
486
Display messages and
warning/indicator lamps

W
W
ar
ar ning/indicat
ning/indicat or lampP
or lam pP ossible causes/conseq
ossible causes/consequences and uences and0050
0050Solutions
Solutions
003D
Electrical fault warning lamp *T
hered electrical fault warning lamp is lit.
There is a fault in the electrics. #
Notethe messages on the instrument displa y.
00D4
Fu elreser vewarning lamp
lights up *T
he yellow fuel reser vewarning lamp lights up while the engine is running.
The fuel supply has dropped into there ser verange. #
Refuel. Display messages and
warning/indicator lamps
487
487

Pa
rking.................................................. 269
System limitations..................................2 68
A
A ctiv
ctiv e Ser
e Ser vice Sy
vice Sy st
stem PL
em PL US
US
see ASS YST PLUS
A
A ctiv
ctiv e Speed Limit Assist
e Speed Limit Assist
Display................................................... 239
Fu nction................................................ 239
A
A ctiv
ctiv eSt
e St eer
eer ing Assist
ing Assist
Ac tivating/deactivating.......................... 243
Ac tive Emer gency Stop Assist................ 243
Fu nction................................................ 241
System limits......................................... 241
A
A dap
dap tiv
tive br
e br ak
ake lights
e lights .................................... 229
A
A dap
dap tiv
tive cr
e cr uise contr
uise contr ol
ol
see Active Distance Assist DISTRONIC
A
A dap
dap tiv
tive Highbeam Assist
e Highbeam Assist
Ac tivating/deactivating.......................... 144
Fu nction................................................ 143
A
A dap
dap tiv
tive Highbeam Assis
e Highbeam Assist Plus t Plus
Fu nction................................................ 144
Switching on/o..................................... 145
A
A dBlue
dBlue ®
®
Ad ditives................................................ 400 Capacity................................................ 401
No tes..................................................... 195
Purit y.................................................... .400
To pping up............................................ .196
A
A dditional door lock
dditional door lock ....................................... 84
A A dditiv dditiv es
es
Ad Blue ®
................................................ .400
Engine oil............................................... 401
Fu el....................................................... 398
A
A dditiv
dditiv es (A
es (AdBlue
dBlue ®
®
)
)
see AdBlue ®
A A dditiv dditiv es (engine oil)
es (engine oil)
see Additives
A
A dditiv
dditiv es (fuel)
es (fuel)
see Fuel
A
A djus
djus ting t
ting t he headlam
he headlam p r
p range
ange ...................... 139
ATer
ATer -sales
-sales ser
service
vice
see ASS YST PLUS
Air conditioning menu
Air conditioning menu Calling up.............................................. 158
Air dis
Air distr tribution
ibution
Setting................................................... 157
Setting (MBUX multimedia system)......... 159 Air inlet
Air inlet
see Air-water duct
Air pr
Air pr essure
essure
see Tyre pressure
Air v
Air v ents
ents
Ad justing (front)..................................... 164
Ad justing (rear)...................................... 165
Air v
Air v ents
ents
see Air vents
Air
Air -conditioning syst
-conditioning syst em
em
see Climate cont rol
Air
Air -r
-recir
ecir culation mode (wit
culation mode (wit h
h/ne
/ne
par
par ticle
ticle pr
pre/lt
e/lt er)
er).......................................... 159
Air
Air -w
-wat
ater duct
er duct
Ke eping free.......................................... 343
Airbag
Airbag
Activation................................................ 47
Fr ont airbag (driver, front passenger)........ 52
Installation locations................................ 52
Knee airbag............................................. 52
Overview.................................................. 52
PA SSENGER AIR BAG indicator la mps...... 57
Pro tection................................................ 53
Re duced pr otection.................................. 54 496 496
Index

Side airbag.............................................. 52
Wi ndow airbag......................................... 52
Air0 ow
Air0ow
Setting................................................... 157
Alar
Alar m syst
m syst em
em
see ATA (anti-theT alarm system)
All-wheel dr
All-wheel dr ive
ive
see 4M ATIC
Ambient lighting
Ambient lighting Setting (MBUX multimedia system)........ .146
Andr
Andr oid A
oid A uto
uto
see Smartphone integ ration
Animals
Animals Pets in theve hicle.................................... 80
Anti-loc
Anti-loc k br
k braking syst
aking syst em
em
see ABS (Anti-lock Braking System)
Anti-skid c
Anti-skid c hains
hains
see Sn owchains
Anti-t
Anti-theT heTprot
pr otection
ection
Ad ditional door loc k................................. 84
Immobiliser............................................ 102
Anti-t
Anti-theT heTprot
pr otection
ection
see ATA (anti-theT alarm system) Anticipat
Anticipat
or
ory occupant pr ot
y occupant pr otection
ection
see PRE-SAFE ®
(anticipatory occu-
pant pr otection)
see PRE-SAFE ®
PLUS (anticipatory
occupant pr otection plus)
Apple CarPlay
Apple CarPlay ®
®
see Smartphone integ ration
Assist
Assist ance syst
ance syst ems
ems
see Driving saf ety sy stem
ASS YS
ASS YST PL
T PL US
US
Battery disconnection period s................ 337
Displaying the service due dat e.............. 336
Fu nction/no tes...................................... 336
Re gular maintenance work..................... 336
Special service requ irements................. 336
AT
ATA A(anti-t
(anti-theT heTalar
alarm syst
m syst em)
em)
Deactivating the alarm........................... 103
Fu nction................................................ 102
Interior pr otection function.....................1 04
Priming/deactivating interior pr otec-
tion........................................................ 104
Priming/deactivating tow- awa y pro-
te ction................................................... 104
To w- awa y protection function................. 103 A
A TTENTION ASSIST
TTENTION ASSIST
Function................................................ 230
Setting.................................................. .232
System limitations.................................. 230
A
A tt
tt ention assist
ention assist ant
ant
see ATTENTION ASSIST
A A ut ut hor
hor ised w
ised w ork
orkshop
shop
see Quali/ed specialist workshop
A
A ut
ut omatic car w
omatic car w ash mode
ash mode
Ac tivating............................................... 345
A
A ut
ut omatic co-dr
omatic co-dr iv
iver airbag
er airbag shut
shuto.
o.
Fu nction of co-driver airbag shuto........... 55
A
A ut
ut omatic dist
omatic dist ance contr
ance control
ol
see Active Distance Assist DISTRONIC
A
A ut
ut omatic dr
omatic dr iving lights
iving lights ................................ 139
A
A ut
ut omatic engine st
omatic engine st art
art
see ECO start/stop function
A
A ut
ut omatic engine st
omatic engine st op
op
see ECO start/stop function
A
A ut
ut omatic fr
omatic fr ont passeng
ont passeng er airbag
er airbagshut
shut o.
o.
PA SSENGER AIR BAG indicator la mps...... 57
A
A ut
ut omatic measur
omatic measur es
esaTer
aTer an accident
an accident........... .60 Index
497
497

Ac
tivating/deactivating the A/C func-
tion (control panel).................................1 58
Ac tivating/deactivating the A/C func-
tion (MBUX multimedia system).............. 158
Ac tivating/deactivating the synchro-
nisation function (control panel).............1 59
Ac tivating/deactivating the synchro-
nisation function (MBUX multimedia
system).................................................. 159
Air-recirculation mode (with /ne parti-
cle pre/lter)...........................................1 59
Au tomatic control................................. .158
Calling up the air conditioning menu....... 158
Demisting the windscreen...................... 157
Demisting windo ws................................ 159
Fr ont air vents........................................ 164
Immediate pre-entry clima tecont rol....... 162
No te...................................................... 157
Pre-entry climate control at depa rture
time.......................................................1 61
Pre-entry climate control using theke y... 160
Re ar air vents......................................... 165
Re sidual heat......................................... 159
Setting (MBUX multimedia system)......... 158
Setting the air distribution...................... 157
Setting the air0ow.................................. 157 Setting
theve hicle interior temp era-
ture....................................................... 157
St ationary heater/ ventilation................. 163
Switching there ar wind owheater
on/o.................................................... 157
THERM ATIC cont rol panel...................... 157
THERMOTRONIC control panel............... 157
Ve ntilating theve hicle (con venience
opening).................................................. 96
Clot
Clot hes hook hes hook ................................................ 129
Co-dr
Co-dr iv
iver airbag
er airbag shut
shuto.
o.
see Automatic co-driver airbag shuto.
Coc
Coc kpit
kpit
Overview.............................................. 6, 10
Co.ee
Co.ee cup symbol
cup symbol
see ATTENTION ASSIST
Collision det
Collision det ection (park
ection (parked v
ed vehicle)
ehicle)
Information............................................ 221
Combination switch
Combination switch .................................... .140
Com
Com ponent-speci/c
ponent-speci/c inf
infor
ormation
mation................... 394
Com
Com put
puter
er
see On-board computer
Conv
Conv enience closing
enience closing...................................... 97 Conv
Conv
enience opening
enience opening..................................... 96
Coolant (engine)
Coolant (engine) Levelch eck............................................ 342
No tes..................................................... 404
Cooling
Cooling see Climate control
Cop
Cop yr
yright
ight....................................................... 45
Cor
Cor ner
nering light
ing light............................................. 142
Cr
Cr oss
oss tr
tra1c
a1c (w
(war
arning)
ning)
see Manoeuvring assis tance
Cr
Cr oss
oss Tr
Tra1c
a1c Alert
Alert........................................ 273
Cr
Cr osswind Assist
osswind Assist
Fu nction/no tes...................................... 226
Cr
Cr uise contr
uise contr ol
ol
Ac tivating............................................... 233
Buttons.................................................. 233
Calling up a speed................................. 233
Deactivating........................................... 233
Fu nction................................................ 232
Maximum design speed.......................... 182
Re quirements:....................................... 233
Selecting............................................... 233
Setting a speed...................................... 233 Index
501 501

006F
2nd seat row, right Not loc ked...... 437
003D 12 V battery See Owner's Man-
ual......................................................... 467
ò Acoustic presence indicator
inoperative............................................ .426
: Active Light System inoperative..... 420
0099 AdBlue system fault Emer. op.:
max. XXX km/h Start not poss. in
XXX km.................................................. 476
0099 AdBlue system fault Emer gency
op. in XXX miles See Owner's Manual.... 475
0099 AdBlue system fault Engine
start not possible................................... 476
0099 AdBlue system fault See Own-
er's Manual............................................ 475
00B3 Add 1 litre engine oil when next
re fuelling ............................................... 477
é ATTENTION ASSIST inoperati ve..... 451
é ATTENTION ASSIS T:Take a
break!.................................................... 451 :
Automatic driving lights inoper-
ative...................................................... 420
00D7 Battery overheated Stop, every-
body out! Outdoors if possible ................ 428
û Before starting the engine, turn
th e steering wheel.................................. 435
004D Brake immediately ........................ 450
Á Change key batteries .................... 417
00E5 Charger cable connected .............. 426
004D Check brake 0uid le vel.................. 450
ï Check trailer hitch lock (white
display message) .................................... 432
0077 Check tyre(s) ................................ 470
003A Clean the fuel /lter....................... 440
ÿ Coolant Stop vehicle Switch
engine o............................................... 439
0025 currently una vailable See Own-
er's Manual............................................4 62
00E5 currently una vailable See Own-
er's Manual............................................4 6300B3
Engine oil le vel cannot be meas-
ured....................................................... 478
00B3 Engine oil le velRe duce oil le vel..... 477
00B3 Engine oil le velSt op vehicle
Switch engine o.................................... 477
00B3 Engine oil pressure Stop Switch
o. engine.............................................. 478
ä Fault Drive at max. 80 km/h ......... 461
0075 Front leT malfunction Consult
wo rkshop (e xample)...............................4 14
003B inoperative Battery low................. 423
003B inoperative Char geHV battery...... 424
003B inoperati veHigh-voltage battery
ch arging inco mplete ............................... 424
003B inoperative Refuel vehicle............. .424
003B inoperative See Owner's Man........ 423
0025 inoperative See Owner's Manual.. .463
00E5 inoperative See Owner's Manual.. .464
007A inoperative See Owner's Manual.. .465
0053 Inoperative................................... 466 Index
503 503