warning light MERCEDES-BENZ A-CLASS SEDAN 2021 Owner's Guide

Wa
rning/indicat orlam p
Possible causes/conseq uencesand0050 0050
Solutions
ÿ Coolant warning lam p(yel‐
lo w) *T
he yello wcoolan twa rning lam pis lit while theengine isrunning .
Po ssible causes:
R The temp eratur esensor ismalfunct ioning
R The charge air,tr ans miss ionoilorbat tery cool ingisfaulty #
Avoiding highloads ontheengine, drive to thenear estqu alif ied spec ialistwo rkshop.
00B9
Engine diagnosis warning
lam p *T
he yello wChec kEn gine warning lam pis lit while theengine isrunning .
A ma lfunctio nha soccu rred intheengine, theex haus tsy stem orthefuel system.
The emission limitvalues maybe exc eeded andtheengine maybe inemer gency mod e.
In som est at es, legalrequ iremen tsstipulat eth at youmus timm ediat elyco nsult aqu alif ied spec ialistwo rkshop as
soon astheye llo wChec kEn gine warning lam plight sup. #
Have theve hicle checkedas soon aspossible ataqu alif ied spec ialistwo rkshop.
003D Electr icalmalfunction warn‐
ing lam p *T
heredelect rical fault warning lam pis lit.
Ther eis afa ult intheelectr ics. #
Notethemessag eson themultifunc tiondispla y. 38
4
Displa ymessag esand warning/ indic ator lam ps

Wa
rning/indicat orlam p
Possible causes/conseq uencesand0050 0050
Solutions
00D4 Fu elreser vewarning lam p
fl ashes *T
he yello wfuel reser vewarning lam plight sup while youar edr ivin g.
Ther ehas been press ureloss inthefuel system. Thefuel filler cap isno tclos edcor rectly orthefuel system isleak‐
ing. #
Close thefuel filler cap.
If th efuel filler cap hasalready been closedcor rectl y: #
Consul ta qu alif ied spec ialistwo rkshop.
00D4 Fu elreser vewarning lam p
light sup *T
he yello wfuel reser vewarning lam plight sup while theengine isrunning .
The fuelsu pp lyhas dropped intoth ere ser verang e. #
Refuel . Displ
aymessa gesand warning/ indic ator lam ps 385

Br
ak es Wa
rning/indicat orlam p
Possible causes/conseq uencesand0050 0050
Solutions
0049 Elect ric pa rking brak eindi‐
cat orlam p(red) (USAonl y)
0024
Elec tric par kingbr ak eindi‐
cat orlam p(red) (Canada
onl y)
0024 The elect ric pa rking brak e
(y ello w)indic ator lam p *T
he redelect ric pa rking brak eindic ator lam pflashes orislit.
The yello welect ric pa rking brak eindic ator lam palso lightsup intheeve ntofama lfunctio n. #
Notethemessag eson themultifunc tiondispla y. 386
Displa ymessag esand warning/ indic ator lam ps

Dr
ivin gsy stems Wa
rning/indicat orlam p
Possible causes/conseq uencesand0050 0050
Solutions
00D4 Ac tiveBr ak eAssi stwa rning
lam p *T
he whit eAc tiveBr ak eAssi stwa rning lam pis lit.
The system isswitc hedoffor una vailable.
L Wa rning lam pfo rdis tance
wa rning func tion *T
he reddis tance warning lam plight sup while theve hicle isin mo tion.
The distance totheve hicle infront istoosmall forth espeed selected.
If th er eis an additional warning tone, youar eappr oachingan obs tacle attoohigh aspeed. #
Beprepar edtobrak eimmediat ely. #
Incr ease thedis tance.
Fu nctio nof ActiveBr ak eAssi st(/ pag e17 3). Dis
play messa gesand warning/ indic ator lam ps 389

Wa
rning/indicat orlam p
Possible causes/conseq uencesand0050 0050
Solutions
00E5 ESP ®
wa rning lam plight s
up *
The yello wES P®
wa rning lam pis lit while theengine isrunning .
ESP ®
is mal func tioning .
Ot her drivi ng systems anddriving safetysy stems (e.g. BAS)ma yal so be mal functi oning. #
Notethemessag eson themultifunc tiondispla y. &
WA RNIN GRisk ofskid ding ifESP ®
is mal functi oning
If ESP ®
is mal functi oning,ESP ®
canno tcar ryout vehicle stabiliz ation.Inaddit ion,ot her driving safetysy stems
ar eswitc hedoff. #
Drive on car efull y. #
Have ESP ®
ch eckedat aqu alif ied spec ialistwo rkshop. 00BB
ESP ®
OFF warning lam p *
The yello wES P®
OFF warning lam pis lit while theengine isrunning .
ESP ®
is de acti vated.
Ot her driving systems anddriving safetysy stems mayalso beinoper ative. &
WA RNIN GRisk ofskid ding whe ndr ivi ng with ESP ®
de acti vated
ESP ®
do es notact tostabiliz eth eve hicle. Theavailabilit yof fur ther driving safetysy stems isalso limited. #
Drive on car efull y. #
Dea ctivateESP ®
only foras long asthesituation requ ires. Disp
lay mess ages and warning/ indic ator lam ps 39
1

Wa
rning/indicat orlam p
Possible causes/conseq uencesand0050 0050
Solutions
0077 Ti re pressur emonit oring
sy stem warning lam plight s
up *T
he yello wtirepr essur emon itor ing system warning lam p(pr essur eloss/ malfun ction) islit.
The tirepr essur emon itor ing system has detected tirepr ess urelos sin at leas tone ofthetir es. &
WA RNIN GRisk ofan acci dent dueto insuf ficie nttirepr ess ure
R The tires can burst.
R The tires can wearexc essiv elyand/or unevenly .
R The drivi ng charact eristic sas wellas thesteer ing and braking maybe greatl yim pair ed.
Yo uco uld then lose control of theve hicle. #
Obser vethere comme ndedtirepr ess ures. #
Adjus tth etir epr essur eif neces sary. #
Stop theve hicle inaccor dance withth etra ffic con dition s. #
Chec kth etir epr essur eand thetir es. Displa
ymessag esand warning/ indic ator lam ps 393

Genuin
ewo od (Car e).............................. 263
Glid emod e...............................................1 41 H
Handbr ake
see Electr icpar king brak e
Handlin gch aract eristics (unus ual)....... 287
HAND S-FREEAC CESS ................................ 75
Hazar dwa rning light s.............................. 111
Hazar doussubstances
Inf ormation .................................... ........25
Head restra int
Fr ont (adjus tingmechanicall y)............... 91
Re ar (installin g/remo ving) .....................9 2
Re ar passe nger com partment
(adj ustin g) .............................................9 2
Head-up Display...... ................................206
Ad jus ting disp lay el eme nts(on-bo ard
com puter) ..... ...... .............................. ...206
Ad jus ting thebr ightn ess(on-boar d
com puter) ....................................... ..... 206
Fu nctio n<0011001100110011001100110011001100110011001100110011001100110011
001100110011001100110011001100110011> <0011001100110011001100110011001100110011001100110011001100110011
00110011001100110011>205
Menu (on-bo ardcom puter) ...... ............ 206 Oper
ating thememor yfunc tion ............ 98
Se tting theposition (on-boar dcom‐
put er) ............................................. ..... 206
Switc hingon/off........................... ...... 207
Headla mps
see Automatic driving lights
Headlin er(car e)....................................... 263
Help call
see Mercedes-Benz emergencycallsystem
High beam
Ac tivati ng/d eactiv ating ........... ............110
High-be amflasher ................................... 110
High-be amheadlam ps
Ad aptiveHig hbeam Assis t.............. .....1 12
Hill star tassi st<0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011001100110011
00110011001100110011001100110011> 157
HOLD functio n...... ................................... 156
Fu nctio n/no tes ................................... 156
Swi tching on/of f<0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011001100110011
0011> 156
Home screen (media display)
Ov ervie w ...... .................................... ... 209
Hood Opening/clo sing.................................. 251 I
Iden tificatio nplat e
Engine ................................................. 322
Re frig er ant .......................................... 329
Ve hicle ................................................ 322
Ignition Switc hingon(Start/S topbutt on) ........ 125
Ignit ionkey
see Smar tKey
Imm obiliz er................................................ 84
Indi catorlam ps
see Warning/ indic ator lam ps
Individ ualdrive pr og ram
Con figur ing .......................................... 136
Sel ecting <0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011> 135
Insid ere ar vie wmir ror
see Exterior mir rors
Insp ectio n
see ASSYST PLUS
Ins trument cluster
Fu nctio n/no tes ........................... 201, 202 Inde
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Ins
trum ent Disp lay
Fu nctio n/no tes ................................... 202
Ins trument cluster ...... ........................... 10
Wa rning/ indic ator lam ps................ .....3 79
Ins trument Displa yand on-b oard
co mp uter
Fu nctio n/no tes ...... ............................. 201
Int ellig entLight System
Ad aptiveHig hbeam Assis t.............. .....1 12
Cor nering light <0011001100110011001100110011001100110011001100110011001100110011
001100110011001100110011001100110011> ............112
Int erior ligh ting........ ................................ 114
Ad jus ting ............ .................................. 114
Ambi entlighti ng<0011001100110011001100110011001100110011001100110011001100110011
0011001100110011> ...............114
Re adin glam p.......................................1 14
Swi tch-of fdel aytim e........... ................115
Int erior motion sensor
Ac tivati ng/d eactiv ating ........... ..............86
Fu nctio n<0011001100110011001100110011001100110011001100110011001100110011
001100110011001100110011001100110011> <0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011> 86
In te rn et radio
see TuneIn
iP hon e®
see Sma rtphone integratio n J
Jac k
St or ag elocation .............................. ..... 310
Jum p-startconne ction ............................2 76
Gene ralno tes ...................................... 274 K
KEYLESS- GO
Loc kingth eve hicle ........................ ........ 70
Pr oblem .................................................7 1
Un loc kin gse tting ............................ .......6 7
Un loc kin gth eve hicle ............................7 0
Kic kdow n.................................................. 141
Using ................................................... 141
Knee airbag ................................................ 42 L
Label ing(tires)
see Tire labeling
Lam p
see Interior light ing
Lam ps(Ins trum ent Displa y)
see Warning/ indic ator lam ps Lane
detection (automatic )
se eAc tiveLa ne Keeping Assist
Lane Keeping Assist
see ActiveLa ne Keeping Assist
LA TC H-type (ISOFI X)child seat secur‐
ing system
In stallin g................................................ 56
Light switch
Ov ervie w ............................................. 109
Light ing
see Inte rior lighting
see Lights
Lights .......................................................1 09
Ad aptiveHig hbeam Assis t...................1 12
Au tomatic driving lights..... .................. 110
Comb inationswit ch<0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011> 110
Cor nering light <0011001100110011001100110011001100110011001100110011001100110011
00110011001100110011001100110011> .............112
Haza rdwa rning light s...........................1 11
High beam............ ...............................110
High -beamflasher ................................ 110
Light switch..... .................................... 109
Lo w-beam headlam ps.........................1 09
Pa rking light s.......................................1 09
Re ar foglam p...................................... 109 408
Index

Online
services
Dat ast or ag e ............ .............................. 33
Open-sour cesof tware .............................. 35
Opening thetrunk lidusing your foot
HANDS-FREE ACCES S.................... .......7 5
Oper ating fluids
Ad ditiv es(fuel) ................................ .... 326
Br ak efluid ...................................... .....3 27
Coolan t(en gine) ............................ ...... 327
En gin eoil ............................................ 326
Fu el(gasoline) ................................. ....3 25
No tes ..................... ............................. 323
Re frig er ant (airconditio ningsystem) ...329
Wi ndsh ield wa sher fluid .................. .... 328
Ope ratin gsaf ety
Decl arati on ofconf ormity (wirel ess
ve hicle component s)............................. 26
Inf ormation ............................................ 25
Oper ating system
see On-bo ardcom puter
Oper ator' sMan ual
Ve hicle equipment ................................. 23
Oper ator's Manual (digital) ......................2 0 Ov
erhead controlpanel
Ov ervie w .......................................... ...... 14 P
Pa int code ................................................ 322
Pa intw ork(cleaning instructions) .........2 60
Pa nic alar m................................................ 67
Ac tivati ng/d eactiv ating ........... ..............67
Pa nor ama roof wit hpo we rtil t/s lidin g
pane l
see Sliding sunroo f
Pa rk pos ition
Inser ting<0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011001100110011
0011> .............138
Sel ecting automatical ly<0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011> 138
Pa rking
see Elec tric par kingbr ak e
Pa rking aid
see Parking AssistPA RK TRONI C
Pa rking Assis tPA RK TRONI C<0011001100110011001100110011001100110011001100110011001100110011
00110011> 189
Ac tivati ng ........... ................................. 193
Ad jus ting warning tones <0011001100110011001100110011001100110011001100110011001100110011
001100110011001100110011> 194
Fu nctio n<0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011> <0011001100110011001100110011001100110011001100110011001100110011
0011001100110011>189
Sid eim pa ct protect ion ..................... ... 192 Swi
tching off<0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011> 193
Sy stem limit ations ...............................1 89
Pa rking assis tance systems
see ActivePa rking Assist
Pa rking brak e
see Elec tric par kingbr ak e
Pa rking foran extended period .............. 150
Pa rking light s...........................................1 09
Pa rking posit ion
Ex terior mir rors <0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011001100110011
0011001100110011> 119
St or ing theposition ofthefront -
passeng eroutside mirrorusi ng
re ve rsege ar .........................................1 20
PA SSEN GERAIRBAGstatus displa y
see Automatic front pass engerfront
airb agshut off
Pa yload
Calculat ionexam ple ............................ 297
De term inin gth emaximum .................. 296
Pe riod out ofuse
Ac tivati ng/d eactiv ating standb y
mode ...................................................1 51
St andb ymode function ........................ 151 41
2
Inde x

Re
star tin gth etir epr essur emonit or‐
ing system ...........................................2 93
Ro tating ........... ........... ...................... ...310
Sel ectio n<0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011> 307
Sno wch ains ........................................ 288
Spe edrating ........... .............................302
St or ing .................................................3 10
Te mp eratur egr ade .............................. 299
Ti re and Loadi ngInfo rm atio nplacar d
.. ...................................................... .....2 95
Ti re pressur e(no tes) ........................... 288
Ti re pressur eloss warning system
(funct ion)............................................. 294
Ti re pressur emonit oring system
(funct ion)............................................. 291
Ti re pressur eta ble .......................... .... 290
Ti re Qua lityGradi ng .......... ................... 299
Ti re size designation ............................3 02
TIREFIT kit....... ....................................268
Tr act ion grade ................................ .....2 99
Tr ead weargrade ............................ .....2 99
Un usual handlingch aract eristic s.........2 87
To ol
see Vehicle tool kit
To pTe ther .................................................. 58 To
uc hCon trol
On-board computer ...... ....................... 203
Oper ating .............................................210
To uc hpad ..................................................210
Oper ating ............................................. 210
To uc hscr een(media display)
Oper ating .............................................210
To w- aw ay alar m
Ac tivati ng/d eactiv ating ........... ..............85
Fu nctio n<0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011> <0011001100110011001100110011001100110011001100110011001100110011
001100110011001100110011>85
To w- bar system .......................................2 00
To w- star ting .............................................283
To wing away <0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011001100110011
001100110011001100110011001100110011001100110011> 279
To wing eye
Ins talling .............................................. 282
St or ag elocation .............................. ....2 82
To wing methods ...................................... 278
Tr actio ngr ade ......................................... 299
Tr af fic inf orma tion
Swit ching onthedispla y.................. ....2 25
Tr af fic Sign Assis t.................................... 178
Fu nctio n/no tes .................................... 178 Se
tting <0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011001100110011
0011001100110011001100110011001100110011001100110011001100110011
0011> 179
Sy stem limit ations ...............................1 78
Tr ansmis sion(pr obl em) .......................... 139
Tr ansmis sionposi tion displa y....... .........137
Tr anspo rting
Ve hicle .................................................2 81
Tr ead weargrade .....................................299
Tr im element (Care)................................ 263
Tr unk lid
Clo sing ...................................................74
Emerg encyrelease (from insid e)............ 76
HANDS-FREE ACCES S...........................7 5
Opening .................................................7 3
Opening dimensions ............................3 30
Tu neIn .......................................................2 47
Callin gup .............................................2 47
Tu rn signal indicat or................................ 110
Tu rn signal light
Ac tivati ng/d eactiv ating ........... ............110
Tw o-w ayradio s
Fr eq uencies ......................................... 321
No teson installation ...........................3 20 Inde
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