2018 MERCEDES-BENZ A-CLASS SALOON check engine

#
close the bonn et.
To pping up engine oil &
WARNING Risk of bu rns from hot com‐
ponent parts in the engine compartment
Cer tain components in the engine compart‐
ment can be very hot, e.g. the engine, the
ra diator and parts of theex haust sy stem. #
Allow the engine tocool down and only
to uch co mponent parts described in the
fo llowing. &
WARNING Risk offire and injury from
engine oil
If engine oil comes into con tact wi thhot
component parts in the engine compart‐
ment, it may ignite. #
Make sure that no engine oil is spilled
next tothefiller opening. #
Allow the engine tocool off and thor‐
oughly clean the engine oil from compo‐
nent parts before starting theve hicle. *
NO
TEEngine dama gecaused byan
incor rect oil filter, incor rect oil or addi‐
tives #
Do not use engine oils or oil filters
which do not cor respond tothe specifi‐
cations explicitly prescribed forthe
service inter vals. #
Do not alter the engine oil or oil filter in
order toachie velonger change inter vals
th an presc ribed. #
Do not use additives. #
Follow the instructions in the service
inter val display rega rding the oil
ch ange. *
NO
TEDama gecaused bytopping up too
much engine oil To
o much engine oil can damage the engine
or the catalytic con verter. #
Have excess engine oil remo ved at a
qu alified specialist workshop. #
Turn cap 1anti-clockwise and remo veit. #
Top up the engine oil. #
Replace cap 1and turn it clockwise as far
as it will go. #
Check the oil le vel again (/ page 433).434
Maintenance and care

Checking
the coolant le vel &
WARNING Risk of bu rns from hot com‐
ponent parts in the engine compartment
Cer tain components in the engine compart‐
ment can be very hot, e.g. the engine, the
ra diator and parts of theex haust sy stem. #
Allow the engine tocool down and only
to uch co mponent parts described in the
fo llowing. &
WARNING Risk of scalding from hot
coolant
The engine cooling sy stem is pressurised,
particularly when the engine is warm. If you
open the cap, you could be scalded byhot
coolant spr aying out. #
Let the engine cool down before open‐
ing the cap. #
When opening the cap, wear pr otective
gl ove s and saf etygl asses. #
Open the cap slowly torelease pres‐
sure. #
Park theve hicle on a le vel sur face. #
Check the coolant temp erature display in the
instrument clus ter.
The coolant temp erature must be below
70 °C. #
Slowly turn cap 1anti-clockwise torelease
ove rpressure. #
Continue turning cap 1anti-clockwise and
re mo veit.
The coolant le vel is cor rect in thefo llowing
cases:
R ifth e engine is cold, the coolant is up to
mar ker bar 2.
R ifth e engine is warm,th e coolant is up to
1. 5 cm overth e mar ker bar 2. #
If necessar y,top up with coolant that has
been appr ovedfo r Mercedes-Benz.
R Further information on coolant
(/ page 503). To
pping up the windsc reen washer sy stem &
WARNING Risk of bu rns from hot com‐
ponent parts in the engine compartment
Cer tain components in the engine compart‐
ment can be very hot, e.g. the engine, the
ra diator and parts of theex haust sy stem. Maintenance and care
435

&
WARNING Risk ofexplosion from a fro‐
zen battery
A dischar ged battery may freeze at temp era‐
tures slightly abo veor below freezing point.
During starting assis tance or battery charg‐
ing, bat tery gas may be released. #
Alw aysth aw a frozen bat tery out first
before charging it or per form ing start‐
ing assis tance. If
th e indicator/warning lamps in the instrument
clus ter do not light up at low temp eratures, it is
ve ry likely that the dischar ged battery has fro‐
zen. In this case you may neither jump-s tart the
ve hicle nor charge the batter y.
The service life of a battery that has been
th awe d may be dramatically shor tened. The
st arting characteristics may be impaired, espe‐
cially at low temp eratures.
It is recommended that you ha veathaw ed bat‐
te ry checked at a qualified specialist workshop. *
NO
TEDama gecaused bynumerous or
ex tended attem ptsto start the engine Nume
rous or extended attem ptsto start the
engine may damage the catalytic con verter
due tonon-combu sted fuel. #
Avoid numerous and extended attem pts
to start the engine. Obser
vethefo llowing points during starting
assis tance and when charging the battery:
R Only use undamaged jump lead/charging
cables with a suf ficient cross-section and
insula tedte rm inal clamps.
R Non- insulated parts of thete rm inal clamps
must not come into con tact wi thother me tal
parts while the jump lead/charging cable is
connected tothe battery/jump-s tart connec‐
tion point.
R The jump lead/charging cable must not
come into contact wi thany parts which may
mo vewhen the engine is running.
R Alw ays make sure that nei ther you nor the
battery is elect rostatically charge d. R
Keep away from fire and naked flames.
R Do not lean overth e batter y.
Obser vethe additional following points when
ch arging the battery:
R Only use battery charge rs tested and
appr oved for Mercedes-Benz.
R Read the battery charge r's operating instruc‐
tions before charging the batter y.
Obser vethe additional following points during
st arting assis tance:
R Starting assis tance may be pe rformed using
only batteries with a nominal voltage of 12V.
R The vehicles must not touch.
R Petrol engine: only acceptstarting assis‐
ta nce if the engine and exhaust sy stem are
cold. 458
Breakdown assis tance

#
Vehicles with automatic transmission
must not be tow- star ted. #
Vehicles with automatic transmission must
not be tow- star ted.
Ve hicles with manual transmission #
Obser vethe no tes on towing away
( / page 461). #
If necessar y,allow the engine and exhaust
sy stem tocool down. #
Switch the ignition on. #
Enga gesecond gear. #
Release the electric parking brake. #
Tow- start theve hicle while the clutch pedal
is fully depressed. #
Slowly release the clutch pedal. #
Immediately shift toneutral if the engine
st arts. #
Pull over and stop theve hicle, paying atten‐
tion toroad and traf fic conditions. #
Remo vetheto w bar. #
Remo vetheto wing eye. #
Have theve hicle checked at a qualified spe‐
cialist workshop. Electrical fuses
Note
s on electrical fuses &
WARNING Risk of accident and inju ry
due to ov erloaded lines
If yo u manipulate or bridge a faulty fuse or if
yo ure place it with a fuse with a higher
amperage, the electric line could be overloa‐
ded.
This could result in a fire. #
Alw aysre place faulty fuses with speci‐
fi ed new fuses conta iningthe cor rect
amperage. *
NO
TEDama gedue toincor rect fuses Electrical components or sy
stems may be
damaged byincor rect fuses, or their func‐
tionality may be significant lyimpaired. #
Only use fuses that ha vebeen appr oved
by Mercedes-Benz and which ha vethe
cor rect fuse rating. Blown fuses mu
stbe replaced with fuses of the
same rating, which you can recognise bythe col‐
our and fuse rating. The fuse ratings and fu rther
information tobe obser ved are lis ted in the fuse
assignment diagram.
Fu se assignment diag ram: onthe fuse box in
th e engine compartment (/ page 466).
* NO
TEDama geor malfunctions caused
by moisture Moisture may cause dama
getothe electrical
sy stem or cause it tomalfunction. #
When the fuse box is open, make sure
th at no moisture can enter the fuse
box. #
When closing the fuse box, make sure
th at the seal of the lid is positioned cor‐
re ctly on the fuse box. Breakdown assis
tance 465

Ad
Blue ®
re sidues cr ystallise af ter a period of
time, and contamina tethe sur faces wi thwhich
th ey come into contact. Clean the dirty sur faces
wi th wate r as soon as possible.
When you open theAd Blue ®
tan k,small
amounts of ammonia vapour may escape. Do
not inhale any ammonia vapours that may be
re leased. Only fill th eAd Blue ®
tank in well-venti‐
lated areas.
Ad Blue ®
filling capacity and consum ption
To tal capacity of AdBlue ®
tank Mode
lT otal capacity
All models 23.8 lAd
Blue ®
consu mption
Like fuel consu mption, AdBlue ®
consu mption is
highly dependent upon driving style and operat‐
ing conditions. Forth is reason, your vehicle's
actual consum ption figures under normal operat‐
ing conditions may dif fer from the consum ption
fi gures calculated. AdBlue ®
consu mption is
between 1% and 5% of fuel consumption. Ha veth
eAd Blue ®
supply checked at a qualified spe‐
cialist workshop before making journe ysoutside
of Europe. Before a longer stay outside of
Europe, consult a qualified specialist workshop.
Display theAd Blue ®
ra nge and le vel
( / page 260). Engine oil
Note
s on engine oil
Obser vethe no tes on operating fluids
(/ page 496). *
NO
TEEngine dama gecaused byan
incor rect oil filter, incor rect oil or addi‐
tives #
Do not use engine oils or oil filters
which do not cor respond tothe specifi‐
cations explicitly prescribed forthe
service inter vals. #
Do not alter the engine oil or oil filter in
order toachie velonger change inter vals
th an presc ribed. #
Do not use additives. #
Have the engine oil rene we d at regular
inter vals. Mercedes-Benz
recommends that you ha vethe
oil change car ried out at a qualified specialist
wo rkshop.
Only Mercedes-Benz appr oved engine oils may
be used in Mercedes-Benz engines.
Fu rther information on engine oil and oil filters is
av ailable at thefo llowing locations:
R inthe Mercedes-Benz Specifications for
Operating Fluids byentering the designation Te
ch nical da ta501

Display messages
Possible causes/consequences and M
MSolutions
Active Brake Assist Func-
tions currently limited See
Owner's Manual *
Ve hicles with the Driving Assistance Package: Active Brake Assi stwith cross-traf fic function, Evasi veSteering
Assist or PRE‑SAFE ®
PLUS are temp orarily una vailable or only partially available.
Ve hicles without the Driving Assistance pa ckage: Active Brake Assi stistemp orarily una vailable.
The ambient conditions are outside the sy stem limits (/ page195). #
Drive on.
As soon as the ambient conditions are within the sy stem limits, the sy stem will become available again. #
Ifth e display message does not disappear, stop theve hicle while paying attention toroad and traf fic conditions
and restart the engine.
6
Restraint sys. malfunction
Consult workshop *T
herestra int sy stem is faulty (/ page 33). &
WARNING Risk of inju ryor fata l injury due toa malfunction in there stra int sy stem
If th ere stra int sy stem is malfunctioning, restra int sy stem components may be triggered unintentionally or
might not be triggered at all in theeve nt of an accident. This may af fect the seat belt tensioner or airbag, for
ex ample. #
Have there stra int sy stem checked and repaired immediately at a qualified specialist workshop. De
tection of a restra int sy stem fault:
R The restra int sy stem warning lamp 6does not light up when the ignition is switched on.
R The restra int sy stem warning lamp 6lights up continuously or repeatedly during a journe y. #
Consult a qualified specialist workshop immediatel y.522
Display messages and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions #
Ifth e display message does not disappear, stop theve hicle while paying attention toroad and traf fic conditions
and restart the engine. Active Steering Assist cur-
rently unavailable See Own-
er's Manual
*A
ctive Steering Assist is temp orarily una vailable.
The ambient conditions are outside the sy stem limits (/ page211). #
Drive on.
As soon as the ambient conditions are within the sy stem limits, the sy stem will become available again. #
If necessar y,clean the windscreen in the camera's field of vision. #
Check the tyre pressure if necessar y.
À ATTENTION ASSIST: Take a
break! *A
TTENTION ASSIST has de tected fatigue or an increasing la ckof concentration on the part of the driver
(/ page 237). #
If necessar y,take a break.
Traffic Sign Assist inopera-
tive *T
raffic Sign Assist is malfunctioning. #
Consult a qualified specialist workshop.
Active Lane Keeping Assist
currently unavailable See
Owner's Manual *A
ctive Lane Keeping Assist is temp orarily una vailable.
The ambient conditions are outside the sy stem limits (/ page245). #
Drive on.
As soon as the ambient conditions are within the sy stem limits, the sy stem will become available again. Display messages and
warning/indicator lamps 525

Display messages
Possible causes/consequences and M
MSolutions #
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. #
Switch off the engine. #
Add 1 l engine oil. #
Check the engine oil le vel.
To p up engine oil (/ page 434).
No tes on engine oil (/ page 501).
4 Engine oil pressure Stop
Switch off engine *D
isplay message only for cer tain engines:
The engine oil pressure is too lo w.
* NO
TEEngine dama gecaused bydriving with insuf ficient engine oil pressure #
Avoid driving with insuf ficient engine oil pressure. #
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. #
Consult a qualified specialist workshop.
4 *D
isplay message only for cer tain engines:
The engine oil le vel has dropped tothe minimum le vel. 536
Display messages and warning/indicator lamps