check engine MERCEDES-BENZ CLA COUPE 2018 Owner's Guide

Checking and addingother service
products
Checking coolan tlevel
GWARNING
The coolings ystem is pressurized, particularly
when th emotor is warm .Ifyou open th ecap,
you coul dbescalded if hot coolant sprays out.
Thereisar iskofi njury.
Let th eenginec ooldown before you open the
cap. Wear gloves and eye protection.S lowly
open th ecap to relieve pressure.
!The coolant may only be checked and cor-
recte dwhen th eengineisc ool(coolantt em-
peratur ebelow 10 4‡(40 †) .Checkin gthe
coolantw hen thecoolantt emperatur eis
above1 04‡(40 †) ma yresult in damage to
th ee ngineortot heengin ecoolings ystem.
XPar kthe vehicl eonal evel surface.
Only chec kthe coolan tlevel when th evehicl e
is on alevel surfac eand th eengineh as cooled
down .
XTurn th eSmartKey to position 2in th eigni-
tion loc k(Ypage 122).
XCheckthe coolan ttem perature display in th e
instrumen tcluster.
The coolan ttem perature mus tbebelow
10 4‡ (40 †).
XTurn th eSmartKey to position g
(Ypage 122) in th eignition loc k.
XSlowly turncap : counter-clockwise and to
reliev eexces spressure.
XTurn cap :further counter-clockwise and
remove it .
If th ecoolan tisatt helevel of marke rbar=
in th efiller neck when cold, there is enough
coolan tincoolan texpansion tan k;.
XIf necessary, add coolan ttha thas been tested
and approve dbyMercedes-Benz.
XReplacecap : and tur nitclockwise as far as
it will go.
Fo rfurther information on coolant, see
(
Ypage 318).
Windshiel dwasher system
GWARNIN G
Certain component sintheengin ecom part-
ment, suc hastheengine, radiato rand part s
of th eexhaust system, can become ver yhot.
Working in th eenginec om partmen tposes a
ris kofi njury.
Where possible, let th eenginec ooldown and
touch only th ecom ponent sdescribed in th e
following.
GWARNIN G
Windshield washer concentrate could ignit eif
it comes into contact wit hhot engin ecom po-
nent sort heexhaust system. There is arisko f
fir ea nd injury.
Mak esuret hatnow indshield washer con-
centrat eisspilled next to th efiller neck .
XTo open: pull cap:upwards by th etab.
XAd dthe premixed washer fluid.
XTo close: press cap :onto th efiller neck
until it engages.
If th ewasher flui dlevel drops belo wthe recom-
mended minimum of 1liter, amessage appears
in th emultifunction display promptin gyou to
add washer flui d(
Ypage 216).
Further information on windshield washer fluid/
antifreez e(
Ypage 319).
260Engine compartment
Maintenance and care

the householdrubbish .They
must be collected separately and recycle dtoprotect the
environment.
Dispose of batteries in an
environmentall yfriendly
manner. Take discharged
batteries to aquali fied spe-
cialist workshop or aspecial
collectio npoint for used bat-
teries.
!Hav ethe battery checked regularly at a
qualified specialis tworkshop.
Observe the service intervals in the Mainte-
nanc eBookle torcontact aquali fied specialist
workshop for mor einformation.
!Yo us houl dhavea llwork involvin gthe bat-
tery carrie doutataq uali fied specialis twork-
shop. In the exceptiona lcas et hatiti sneces-
sary for yo utodisconnect the battery your-
self, make sure that:
Ryo us witch off the engine and remove the
key .Onv ehicles with KEYLESS-GO, ensure
thatt he ignition is switched off .Check that
al lt he indicator lamps in the instrument
clustera reoff .O therwise, electronic com-
ponents ,suc hast he alternator, mayb e
damaged.
Ryo uf irst remove the negative terminal
clamp and thent he positive terminal
clamp. Never swap the termina lclamps.
Otherwise, the vehicle' selectronic system
maybed amaged.
Rin vehicles with automatic transmission,
the transmission is locked in position P
after disconnecting the battery .The vehicle
is secur ed a
gainst rolling away
.You can
thennol ongerm ovet he vehicle.
The battery and the cove rofthe positive ter-
minal clamp must be installe dsecurel yduring
operation.
Compl ywiths afety precautions and take pro-
tective measures when handling batteries.
Risk of explosion.
Fire, open flames and smoking are
prohibited when handling the bat-
tery .Avoi dc reating sparks.
Battery aci discaustic. Avoidc ontact
with skin, eyes or clothing.
Wear suitabl eprotective clothing,
especiall ygloves, apron and face-
guard.
Rinse any aci dspills immediately
with clear water. Contact aphysician
if necessary.
Wear ey eprotection.
Kee pchildren away.
Observe thisO perator' sManual.
For safety reasons, Mercedes-Benz recom-
mend sthaty ouonlyusebatteries which have
been tested and approved for your vehicl eby
Mercedes-Benz. Thes ebatteries provide
increasedi mpactprotection to prevent vehicle
occupants froms ufferin gacidb urns shoul dthe
battery be damage dinthe event of an accident.
In order for the battery to achieve the maximum
possibl eservice life, it must always be suffi-
ciently charged.
Like othe rbatteries ,the vehicl ebattery may
discharge ove rtim eify oudo not us ethe vehicle.
In thisc ase, have the battery disconnecte data
qualified specialis tworkshop .You can also
charge the battery with acharge rrecommended
by Mercedes-Benz. Contact aquali fied special-
is tw orkshop for furtheri nformation.
Hav ethe battery condition of charge checked
mor efrequentl yifyouuset he vehicl emainl yf or
short trip sorifyouleav eits tanding idle for a
lengthyp eriod. Consult aquali fied specialist
workshop if yo uwishtol eave your vehicle
parked for alon gp eriodoft ime.
Onlyr eplace abattery with abattery thath as
been recommended by Mercedes-Benz.
Battery (vehicle)277
Breakdow nassistance
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Remove theSmartKey if you park th evehicl e
and do no trequire any electrical consumers.
The vehicl ewill then use ver ylittl ee nergy, thus
conserving battery power .
If th epower suppl yhas been interrupted, e.g. if
you reconnect th ebattery, you will hav eto:
Rset th eclock usin gthe multimedia system;
see th eseparat eoperating instruction s
Rreset thefunction for foldin gthe exterio rmir-
ror sin/out automatically, by foldin gthe mir -
ror so ut once (
Ypage 97)
Charging th ebattery
GWARNIN G
During charging and jump-starting ,explosive
gase scan escape from th ebattery. There is a
ris kofane xplosion .
Particularly avoi dfire, open flames, creating
sparks and smoking. Ensur ethe re is sufficien t
ventilation while charging and jump-starting .
Do no tlean ove rabattery.
GWARNIN G
Battery acid is caustic. There is ariskofi njury.
Avoid contact wit hskin, eyes or clothing .Do
no tinhale any battery gases. Do no tlean ove r
th eb attery. Kee pchildren away from batter-
ies. Wash away battery acid immediately wit h
plenty of clean water and seek medical atten -
tion .
GWARNIN G
Ad ischarged battery can freez eattempera-
tures belo wfreezing point. When jump-start -
ing thevehicl eorc harging th ebattery, gase s
can escape from th ebattery. There is arisko f
an explosion .
Allow th efroze nbattery to thaw out before
charging it or jump-starting .
!Only use battery chargers wit hamaximum
charging voltag eof14.8V .
!Only charge th ebattery usin gthe jump-
starting connection point.
The jump-starting connection poin tisinthe
engin ecom partmen t(
Ypage 278).
XOpen thehood.
XConnect th ebattery charge rtothepositive
termina land ground poin tinthesam eorder
as when connecting th edonor battery in th e
jump-starting procedure (
Ypage 278).
If th eindicator/warning lamp sdonotligh tupi n
th ei nstrumen tcluste ratlow temperatures ,itis
ver ylikely that th edischarged battery has fro-
zen. In this cas eyou may neither jump-start th e
vehicl enorcharge th ebattery. The servic elife of
at hawed-out battery may be shorter. The start -
ing characteristics can be impaired, particularly
at low temperatures .Havet he thawed-out bat -
tery checke dataqualified specialist workshop.
Only charge th einstalled battery wit habattery
charge rwhic hh as been tested and approve dby
Mercedes-Benz .Abattery charge runi
ts p
ecially
adapted for Mercedes-Benz vehicles and tested
and approve dbyMercedes-Benz is available as
an accessory. It permit sthe charging of th ebat-
tery in it sinstalled position .Contac tana uthor-
ized Mercedes-Benz Cente rfor further informa-
tion and availability. Read th ebattery charger's
operating instruction sbefore charging th ebat-
tery.
Jump-starting
Fo rthe jump-starting procedure ,use only th ejump-starting connection point, consisting of apos-
itive termina land aground point, in th eenginec om partment.
GWARNIN G
Battery acid is caustic. There is ariskofi njury.
Avoid contact wit hskin, eyes or clothing .Donotinhale any battery gases. Do no tlean ove rthe
battery. Kee pchildren away from batteries. Wash away battery acid immediately wit hplenty of
clean water and seek medical attention .
278Jump-starting
Breakdown assistance

GWARNING
During charging and jump-starting, explosive gasesc an escapefrom the battery .There is arisk
of an explosion.
Particularl yavoi dfire, open flames, creating sparks and smoking. Ensure there is sufficient ven-
tilation while charging and jump-starting. Do not leano verabattery.
GWARNING
During the charging process,ab attery produces hydrogen gas. If ashort circui toccurs or sparks
are created ,the hydrogen gas can ignite. There is arisk of an explosion.
RMake sure that the positive terminal of aconnected battery does not come into contact with
vehiclep arts.
RNever place metal objects or tools on abattery.
RIt is important that you observe the described order of the battery terminal swhen connecting
and disconnecting abattery.
RWhen jump-starting, make sure that the battery polesw ith identical polarity are connected.
RIt is particularlyimportant to observe the described order when connecting and disconnecting
the jumper cables.
RNever connect or disconnect the battery terminal swhile the engine is running.
GWARNING
Ad ischarged battery can freeze at temperatures below freezing point. When jump-starting the
vehicleorc harging the battery,g asescan escapef rom the battery.T here isarisk of an explosion.
Allow the frozen battery to thaw out before charging it or jump-starting.
!Avoid repeated and lengthy starting attempts. Otherwise, the catalytic converter coul dbe
damaged by the non-combusted fuel.
If the indicator/warning lamp sdonot light up in the instrument cluster at low temperatures, it is very
likelyt hat the discharged battery has frozen. In this case you may neither jump-start the vehiclen or
charge the battery.L et the battery thaw first. The service life of athawed-out battery may be shorter.
The starting characteristics can be impaired,p articularlyatlow temperatures. Have the thawed-out
battery checked at aqualified specialist workshop.
Do not start the vehicleu singarapi dc harging device. If you rvehicle's battery is discharged, the
engine can be jump-started from another vehicleorf romasecond battery using jumper cables.
Observe the following points:
RThe battery is not accessible in all vehicles. If the other vehicle's battery is not accessible,j ump-
start the vehicleu singasecond battery or ajump-starting device.
RYou may only jump-start the vehiclew hen the engine and exhaust system are cold.
RDo not start the engine if the battery is frozen. Let the battery thaw first.
ROnly jump-start from batterieswitha12Vv oltagerating.
ROnly use jumper cables that are not damaged and have asufficient cross-section and insulated
terminal clamps.
RMake sure that the two vehicles do not touch.
Jump-starting279
Breakdown assistance
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Make sure that:
RThe jumper cables are not damaged.
RNon-insulated parts of the terminal clamps do not come into contact with other metal parts while
the jumper cables are connected to the battery.
RThe jumper cables cannot come into contact with parts that can move when the engine is running,
such as the V-belt pulleyorthe fan.
XSecure the vehicle by applying the electric parking brake.
XShift the transmission to position j.
XTurn the SmartKey to positiongin the ignition lock and remove it.
XSwitch off all electrical consumers, e.g. rear window defroster, lighting, etc.
XOpen the hood.
Position number Bidentifies the charged battery of the other vehicle or an equivalent jump-starting
device.
XPress together cover :of positive clamp ;and slide it back.
XConnect positive terminal ;on your vehicle to positive terminal =of donor battery Busing the
jumper cable, beginning with your own battery.
XStart the engine of the donor vehicle and run it at idling speed.
XConnect negative terminal ?of donor battery Bto ground point Aof your vehicle using the
jumper cable, connecting the jumper cable to battery of other vehicle Bfirst.
XIf the battery is fully discharged, leave the battery that is being used to jump-start connected for
afew minutes before attempting to start. This charges the battery slightly.
XStart the engine.
XBefore disconnecting the jumper cables, let the engine run for several minutes.
XFirst, remove the jumper cables from ground point Aand negative terminal ?,then from pos-
itive terminal ;and positive terminal =.Begin each time at the contacts on your own vehicle
first.
XClose cover :of positive terminal ;after removing the jumper cables.
XClose the hood.
XHave the battery checked at aqualified specialist workshop.
iJump-starting is not considered to be anormal operating condition.
280Jump-starting
Breakdown assistance

Fuse box in theengine compartment
GWARNIN G
When th ehoodiso pen and th ewindshield
wiper sare set in motion ,you can be injured by
th ew iper linkage. Ther eisariskofi njury.
Always switch off th ewindshield wiper sand
th ei gnition before opening th ehood.
XOpen th ehood.
XUse adry cloth to remove any moisture from
th ef useb ox.
XTo open :open clamps ;.
XFold up cover :in th edirection of th earrow
and remove it .
XTo close:check whether th eseal is lyin gcor-
rectl yinc over :.
XInser tcover : at th ebacki ntoo pening s=
on th efuseb ox.
XFold down cover :.
XHook clamps;intot he fuseb ox and close.
XClose th ehood.
Fuse box in th efront-passenger foot-
well
XTo open :open th efront-pa ssenger door .
XRemove thefloormat.
XFold out perforate dfloor covering :in th e
direction of th earrow.
XTo release cover =,press retaining
clam p;.
XFold out cover =in th edirection of th earrow
to th ecatch .
Fuses285
Breakdown assistance
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Tire-mounting tools should not be used near
the valve. This could damage the electronic
components.
Only have tires changed ataqualified spe-
cialist workshop.
Observe the instructions and safety notes in the
"Changing awheel" section (
Ypage 307).
The wear pattern sonthe front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before aclear wear pattern
has formed on the tires. Frontt ires typically
wear more on the shoulders and the rear tires in
the center.
On vehicles that have the same size front and
rear wheels, you can rotat ethe wheels accord-
ing to the intervals in the tire manufacturer's
warranty book in your vehicle documents. If no
warranty book is available, the tires should be
rotated every 3,000 to 6,000 miles (5,000 to
10,000k m).D ependin gontire wear, this may
be required earlier. Do not change the direction
of wheel rotation.
Clean the contact surfaces of the wheel and the brake disc thoroughly every time awheel is rota-
ted. Check the tire pressure and, if necessary,
restart the tire pressure loss warning system
(Canada only) or the tire pressure monitor (USA
only).
Direction of rotation
Tires with aspecified direction of rotation have
additional benefits ,e.g. if there is arisk of hydro-
planing. These advantages can only be gained if
the tires are installed corresponding to the
direction of rotation.
An arrow on the sidewall of the tire indicates its
correctd irection of rotation.
Storing wheels
Storewheels that are not being used in acool,
dry and preferably dark place. Protectt he tires
from oil, grease, gasoline and diesel.
Mounting awheel
Preparing the vehicle
XStop the vehicle on solid, non-slippery and
level ground.
XApply the electric parking brake manually.
XBring the front wheels into the straight-ahead position.
XShift the transmission to position j.
XSwitch off the engine.
XVehicles without KEYLESS-GO:remove the
SmartKey from the ignition lock.
XVehicles with KEYLESS-GO start-function
or KEYLESS-GO: open the driver's door.
The vehicle electronics are now in position
u.T his is the same as “key removed”.
XVehicles with KEYLESS-GO start-function
or KEYLESS-GO: remove the Start/Stop but-
ton from the ignition lock (
Ypage 122).
XMake sure that the engine cannot be started
via your smartphon e(Ypage 83).
XIf included in the vehicle equipment, remove
the tire-change tool kit from the vehicle.
XSafeguard the vehicle against rolling away
(Ypage 141).
iApart from certain country-specific varia-
tions, the vehicles are not equipped with a
tire-change tool kit. Some tools for changing a
wheel are specific to the vehicle. For more
information on which tools are required to
perform awheel change on your vehicle, con-
sult aqualified specialist workshop.
Necessary tire-changing tools can include, for
example:
RJack
RWheel chock
RLug wrench
308Changing awheel
Wheels and tires

The antifreeze concentrate/corrosion inhibitor
concentration in the engine cooling system
should:
Rbe at least 50%. This will protectthe engine
cooling system against freezin gdown to
approximately -35 ‡(-37 †)
Rnot exceed 55% (antifreez eprotection down
to -49 ‡[-45 †]) .Otherwise ,hea tw ill no tbe
dissipated as effectively
Mercedes-Ben zrecommends acoolan torc or-
rosio ninh ibitor/antifreez econcentrat ein
accordance wit h
MB Specification sfor Servic eProducts 310. 1.
iWhen the vehicle is first delivered, it is filled
with acoolant mixture that ensures adequate
antifreeze and anti-corrosion protection.
iThe coolant is checked with every mainte-
nanc einterval at aqualified specialist work-
shop.
Filling capacities
ModelCapacity
Mercedes ‑AMG
vehiclesApprox .12.6USq t
(11.9l )
Allo ther modelsApprox. 8.2 US qt
(7.8 l)
Windshield washe rsystem
Important safety notes
GWARNING
Windshieldw asher concentrate coul dignite if
it comes into contact with hot engine compo-
nents or the exhaust system .There is arisk of
fire and injury.
Make sure that no windshield washer con-
centrate is spilled next to the filler neck.
!Only MB SummerFi tand MB WinterFit
washer flui dshould be mixed together. The
sprayn ozzles may otherwise become
blocked.
Do not use distille dorde-ionized water. Other-
wise, the levels ensor may giveafals ereading. When handling washer fluid, observe the impor-
tant safety notes on service products
(
Ypag
e315).
At temperatures above freezing:
XFill the washer flui dreservoir with amixture of
water and windshield washer fluid, e.g. MB
SummerFit.
Add 1part MB SummerFi tto100 parts water.
At temperatures below freezing:
XFill the washer flui dreservoir with amixture of
water and washer fluid, e.g. MB WinterFit.
For the correct mixing ratio refer to the infor-
mation on the antifreeze reservoir.
iAdd windshield washer fluid, e.g. MB Sum-
merFit or MB WinterFit, to the washer flui dall
yea rround.
Climate control system refrigerant
Important safety notes
The climate control system of you rvehicleisf il-
led with refrigerant R ‑134a.
The instruction label regarding the refrigerant
type use dcan be found on the left, on the under-
side of the hood.
!Only the refrigerant R ‑134a and the PAG oil
approved by Mercedes-Benz may be used.
The approved PAG oil may not be mixed with
any other PAG oil that is not approved for
R-134a refrigerant. Otherwise, the climate
control system may be damaged.
Service work, such as refilling with refrigerant or
replacing component parts, may only be carried
out by aqualified specialist workshop. All appli-
cabl eregulations, as wellasS AE standard J639,
must be adhered to.
Always have work on the climate control system
carrie dout at aqualified specialist workshop.
Service products and filling capacities319
Technical data
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