check engine MERCEDES-BENZ A-CLASS SALOON 2018 Owner's Manual

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions #
Have there stra int sy stem checked and repaired immediately at a qualified specialist workshop. #
Drive on carefully. #
Obser vethe messages on the multifunction displa y. #
Consult a qualified specialist workshop immediatel y. Seat belt
Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
7 Seat belt warning lamp
lights up The
red seat belt warning lamp will light up once the engine has star ted.
In addition, a warning tone may sound.
The seat belt warning lamp reminds the driver and front passenger tofast entheir seat belts. #
Fasten your seat belt (/ page37).
If yo u ha veplaced objects on the front passenger seat, the seat belt warning lamp may remain lit.
7 Seat belt warning lamp
fl ashes The
red seat belt warning lamp flashes and an intermit tent wa rning tone sounds.
The driver or front passenger has not fastened their seat belt while theve hicle is in motion. #
Fasten your seat belt(/ page37).
There are objects on the front passenger seat. #
Remo vethe objects from the front passenger seat. Display messages and
warning/indicator lamps 567

Driving sy
stems Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
L Wa rning lamp for dis tance
wa rning function The
red dis tancewarning lamp lights up while theve hicle is in motion.
The dis tance totheve hicle in front is too small forth e speed selected.
If th ere is an additional warning tone, you are approaching an obs tacle at too high a speed. #
Be prepared tobrake immediatel y. #
Increase the dis tance.
Fu nction of Active Brake Assi st .Engine
Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
; Engine diagnosis warning
lamp The
yellow engine diagno stics warning lamp is lit while the engine is running.
A malfunction has occu rred in the engine, theex haust sy stem or the fuel sy stem.
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 qualified specialist workshop.
Ve hicles with a diesel engine: the fuel tank may ha vebeen run dr y. 568
Display messages and warning/indicator lamps

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions #
Start the engine thre eto four times af terre fuelling.
If th eye llow engine diagnosis warning lamp goes out, emer gency operation mode is cancelled. The vehicle need not
be checked.
æ Fu elreser ve wa rning lamp The
yellow fuel reser ve wa rning lamp lights up while the engine is running.
The fuel supp lyhas dropped into there ser verange. #
Refuel.
#
Electrical fault warning
lamp The
red elect rical fault warning lamp is lit.
There is a fault in the electrics. #
Obser vethe messages on the multifunction displa y.
?
Coolant warning lamp The
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
If th ere is an additional warning tone, the coolant temp erature has exceeded 120 °C. Displ
aymessa ges and warning/indicator lamps 569

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions &
WARNING Danger of bu rns when opening the bonn et
If yo u open the engine bonn etwhen the engine has overheated or during a fire inthe engine compartment, you
could come into contact wi thhot gases or other escaping operating fluids. #
Before opening the bonn et, allow the engine tocool down. #
Intheeve nt of a fire inthe engine compartment, keep the engine bonn etclosed and call thefire service. #
Stop theve hicle immediately, paying attention toroad and traf fic conditions, and switch off the engine. Do not con‐
tinue driving under any circums tances. #
Obser vethe messages on the multifunction displa y.
If th e coolant temp erature display is at the lo wer end of thete mp erature scale: #
Consult a qualified specialist workshop.
or #
Exit theve hicle and keep a safe dis tance from it until the engine has cooled down. #
Check the coolant le vel (/ page 435). #
Make sure that the air supply tothera diator is not obstructed. #
Avoiding high loads on the engine, drive tothe nearest qualified specialist workshop. In doing so, ensure that the
coolant temp erature display remains below 120 °C. 57 0
Displaymessa ges and warning/indicator lamps

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
Ty re pressure monitoring
sy stem warning lamp
fl ashes &
WARNING Thereis a risk of an accident if the tyre pressure monitoring sy stem is malfunctioning
If th e tyre pressure monitoring sy stem is malfunctioning, it is not able toissue a warning if there is pressure loss in
one or more of the tyres.
Ty res with insuf ficient tyre pressure ma y,forex ample, af fect theve hicle's handling characteristics, steering and
braking. ‑ #
Have the tyre pressure monitoring sy stem checked at a qualified specialist workshop. #
Consult a qualified specialist workshop. Ve
hicle Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
Ð Po we rst eering sy stem
wa rning lamp The
red po werst eering sy stem warning lamp is lit while the engine is running.
The po wer-assis tedsteering or thesteering itself is malfunctioning. &
WARNING Risk of accident if steering capability is impaired
If th esteering does not function as intended, theve hicle's operating saf ety is jeopardised. #
Pull over and stop theve hicle safely as soon as possible, paying attention toroad and traf fic conditions. Do
not continue driving under any circums tances. 572
Displaymessa ges and warning/indicator lamps

Ac
tivating/deactivating the synchro‐
nisation function (cont rol panel) .......... 147
Ac tivating/deactivating the synchro‐
nisation function (multimedia sys‐
te m) ..................................................... 14 8
Air di stribution settings .......................1 47
Air-reci rculation mode ........................ .148
Au tomatic control ................................ 147
Calling up the air conditioning menu ... 147
Defrosting the windscreen ...................1 45
Demisting wind ows............................. 14 8
Fr ont air vents ..................................... 15 3
No te .................................................... 14 5
Re ar air vents ...................................... 154
Re sidual heat ....................................... 14 8
Sets the air flow ................................... 14 5
Setting (multimedia sy stem) ................1 47
Setting the air distribution ...................1 45
Setting thete mp erature ......................1 45
St ationary heater/ ventilation .............. 14 8
Switching on/off ................................. 14 6
Switching there ar wind owheater
on/off .................................................1 45
THERMATIC control panel .................... 14 5
THERMOTRONIC contro l panel ............14 5Ve
ntilating theve hicle (con venience
opening) ................................................ 87
Cockpit ........................................................ .6
Overview .................................................6
Cof fee cup symbol
see ATTENTION ASSIST
Combination switch ................................12 9
Compass .................................................. .371
Compu ter
see On-board computer
Connection status
Displ aying ............................................ 408
Overview ............................................ .408
Connectivity Switching transmission of theve hicle
position on/off .................................... 320
Contacts ................................................... 383
Calling up ............................................ 384
Deleting ............................................... 386
Deleting favo urites .............................. 386
Downloading (from mobile phone) ...... 384
Importing ............................................ 385
Importing (o verview) .......................... .385 Information .......................................... 383
Making a call ....................................... 385
Na me form at ...................................... .384
Options ................................................ 385
Saving as a favo urite .......................... .386
Selecting options for suggestions ........ 386
St oring ................................................ 385
Con venience closing ................................. 87
Con venience opening ................................ 87
Coolant (engine) Check le vel .......................................... 435
No tes .................................................. 503
Cooling see Climate control
Co pyright .................................................... 31
Cornering light ........................................ .131
Cross Traf fic Alert .................................. .236
Crosswind Assist Function/no tes .................................... 194
Cruise control .......................................... 201
Ac tivating ............................................ 203
Buttons ................................................ 203
Calling up a speed ............................... 203 Index
581

Ac
tive Steering Assist cur rently
una vailable See Owner's Manual .........525
Ac tive Steering Assist inoperative .......524
Ad aptive Highbeam Assist cur rently
una vailable See Owner's Manual .........559
Ad aptive Highbeam Assist inopera‐
tive ...................................................... 559
Ad aptive Highbeam Assist Plus cur‐
re ntly una vailable See Owner's Man‐
ual ...................................................... .560
Ad aptive Highbeam Assist Plus inop‐
erative ................................................ .560
¯ AdBlue sy stem fault Engine
st art not possible ................................ 539
¯Ad Blue system fault Perf.
re duced in XXX miles See Owner's
Manual ................................................ 538
¯ AdBlue sy stem fault Perf.
re duced: XXX km/h Nostart in XXX
km ...................................................... .538 ¯
AdBlue sy stem fault See Own‐
er's Manual ........................................ .538
4Ad d 1 litre engine oil when next
re fuelling ............................................. 536
Anti-theft ala rmsystem Malfunction ... 556
Apply brake todeselect Park (P)
position ...............................................5 40
Apply brake toselect R ........................ 543
À ATTENTION ASSIST inoperative ... 526
ÀAT TENTION ASSIS T:Take a
break! .................................................. 525
bAu tomatic driving lights inoper‐
ative .................................................... 559
Au xilia rybattery malfunction ...............541
_ Before starting the engine, turn
th esteering wheel. .............................. 544
Blind Spot Assi stcur rently una vaila‐
ble See Owner's Manual ...................... 523
Blind Spot Assist inope rative ............... 524 Blind Spot Assi
stnot available when
to wing a trailer See Owner's Manual ...5 26
Brake immediate ly............................... 51 0
Á Changekey bat teries .................. 550
JCheck brake fluid le vel................ .515
Check brake pads See Owner's Man‐
ual ...................................................... .523
ïChe cktrailer hitch lo ck(white
display message) .................................5 52
Che cktyre pressu resth en restart
Ru n Flat Indicator ................................ 549
h Check tyre(s) .............................. .546
!Clean the fuel filter ...................... 531
Clutch overheated Avoid pulling away
fo r XX:XX mins .................................... .541
? Coolant Stop vehicle Switch
engine off ............................................ 534
Cruise contro l and Limiter inope ra‐
tive ...................................................... 529
Cruise control inope rative ................... 529 584
Index