engine MERCEDES-BENZ CLA COUPE 2018 Repair Manual

Permanent setting (Mercedes-AMG
vehicles)
XTo activate:shift the selector lever to h.
XPress button:.
XTo deactivate: press button:.
or
XIf position D(automatic transmission) is
selected for the transmission in drive pro-
gram I:shift to drive program Iwith the
DYNAMICS ELECT controller.
Shifting gears
!Mercedes-AMG vehicles: the automatic
transmission does not shift up automatically
even when the engine limiting speed for the
current gear is reached. When the engine lim-
iting speed is reached, the fuel supply is cut to
prevent the engine from overrevving. Always
make sure that the engine speed does not
reach the red area of the tachometer. There is
otherwise arisk of engine damage.
XTo shift up: pull steering wheel paddle
shifter ;.
The automatic transmission shifts up to the
next gear. All vehicles (except Mercedes-AMG vehi-
cles):
if the maximum engine speed on the
currently engaged gear is reached and you
continue to accelerate, the automatic trans-
mission automatically shifts up in order to
prevent engine damage.
XTo shift down: pull steering wheel paddle
shifter :.
The automatic transmission shifts down to
the next gear.
Automatic down shifting occurs when coast-
ing.
If the engine exceeds the maximum engine
speed when shifting down, the automatic
transmission protectsa gainst engine damage
by not shifting down.
Shift recommendation
The gearshift recommendations assist you in
adopting an economical driving style. The rec-
ommended gear is shown in the multifunction
display.
XShift to recommended gear ;according to
gearshift recommendation :when shown in
the multifunction display.
Upshifting (Mercedes-AMG vehicles)
!In manual mode, the automatic transmis-
sion does not shift up automatically even
when the engine limiting speed for the current
gear is reached. When the engine limiting
speed is reached, the fuel supply is cut to
prevent the engine from overrevving. Always
make sure that the engine speed does not
reach the red area of the tachometer. There is
otherwise arisk of engine damage.
Automatic transmission137
Driving and parking
Z

Beforethe engine speed reaches the red area,
an upshift indicator will be shownint he multi-
function display.
XShift to recommende dgear :whe nmes-
sage ;is shownint he multifunction display.
Kickdown
XFor maximum acceleration, depress the
accelerator pedal beyond the pressure point.
The automatic transmission shifts to alower
geard epending on the engine speed.
XShift back up once the desire dspeed is
reached. During kickdown, yo
ucannot shift gears using
the steering wheel paddl eshifters.
If yo uapply fullthrottle ,the automatic trans-
missio nshifts up to the next gearw hent he
maximum engine speed is reached.T hispre-
vents the engine from overrevving.
Mercedes-AMG vehicles: it is only possible to
use kickdown in temporary manual drive pro-
gram M.Whenm anual drive program Mis per-
manently activated, kickdown is not possible.
Problems with the transmission
ProblemPossible causes/consequence sand MSolutions
The transmission has
problem sshifting gear.The transmission is losing oil.
XHave the transmission checkedataq ualified specialist workshop
immediately.
The acceleration ability
is deteriorating.
The transmission no lon-
ger shifts into al lofthe
gears.
Reverseg earcan no lon-
ger be engaged.The transmission is in emergency mode.
XStop the vehicle.
XShift the transmission to position j.
XSwitch off the engine.
XWait at least ten seconds before restarting the engine.
XShift the transmission to positionh.
XHave the transmission checkedataq ualified specialist workshop
immediately.
Refueling
Important safety notes
GWARNING
Fue lish ighly flammable. If yo uhandle fuel
incorrectly ,there is ariskoff ire and explo-
sion.
You mus tavoid fire ,openf lames, creating
sparks and smoking. Switch off the engine
and ,ifa pplicable, the auxiliary heating before
refueling.
GWARNING
Fue lisp oisonousa nd hazardoustoh ealth.
There is arisk of injury.
138Refueling
Drivin gand parking

You must make sure that fuel does not comeint oc ontac twith your skin ,eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors.K eep fuel away from children.
If you or others com eintoc ontac twith fuel,
observet he following:
RWash away fuel from skin immediately
using soap and water.
RIf fuel comes int ocontac twith your eyes,
immediately rinse the mthoroughly with
clean water. Seek medical assistanc ewith-
out delay.
RIf fuel is swallowed, seek medical assis-
tance without delay. Do not induc evomit-
ing.
RImmediately change out of clothing which
has com eintoc ontac twith fuel.
GWARNING
Electrostatic buildup can create sparksa nd
ignit efuel vapors.T here isarisk of fire and
explosion.
Always touc hthe vehicle body beforeo pening
the fuel filler flap or touching the fuel pump
nozzle. An yexisting electrostatic buildup is
thereby discharged.
!Do not use diesel to refuel vehicles with a
gasolinee ngine. Do not switc honthe ignition
if you accidentally refuel with the wrongf uel.
Otherwise, the fuel will enter the fuel system. Even small amount softhe wrongf uel could
result in damage to the fuel syste mand the
engine. Notify aqualified specialis tworkshop
and have the fuel tan kand fuel lines drained
completely.
!Overfilling the fuel tan kcould damage the
fuel system.
!Take care not to spill any fuel on painted
surfaces. You could otherwise damage the
paintwork.
!Use afilter when adding fuel from afuel can.
The fuel lines and/or the fuel injection system
could otherwise be blocked by particles from
the fuel can. Do not get int
othe vehicle again during the refu-
eling process. Otherwise, electrostatic charge
could build up again.
If you overfill the fuel tank, fuel could spray out
when the fuel pump nozzle is removed.
For further information on fuel and fuel quality
(
Ypage 315).
Refueling
Genera linformation
Pay attention to the importan tsafetyn otes
(Ypage 138).
The fuel filler flap is unlocked/locked automat-
ically when you unlock/lock the vehicle with the
SmartKey.
The position of the fuel filler cap is displayed
æ in the instrumentc luster. The arrow on the
filling pump indicates the side of the vehicle.
Opening th efuel filler flap
:To open the fuel filler flap
;Tire pressure table
=To inser tthe fuel filler cap
?Instruction label for fuel type to be refueled
XSwitch off the engine.
XRemove the SmartKey from the ignition lock.
or, in vehicles with KEYLESS-GO start-function
or KEYLESS‑ GO
XOpen the driver's door.
The vehicle electronics are now in position
g.This is the same as the SmartKey being
removed from the ignition.
XPress the fuel filler flap in the direction of
arrow :.
The fuel filler flap swings up.
Refueling139
Driving and parking
Z

XTurn the fuel filler cap counterclockwise and
remove it.
XInsert the fuel filler cap into the holder on theinside of fuel filler flap =.
XCompletely insert the filler neck of the fuel
pump nozzle into the tank ,hook in place and
refuel.
XOnly fill the tank until the pump nozzle
switches off.
Do not add any more fuel after the pump stops
filling for the first time. Otherwise, fuel may leak
out.
Closing the fuel filler flap
XReplace the cap on the filler neck and turn
clockwise until it engages audibly.
XClose the fuel filler flap. Close the fuel filler flap before lockingt
he vehi-
cle.
If you are driving with the fuel filler cap open, the
8 reserve fuel warning lamp flashes. Ames-
sage appears in the multifunction display
(
Ypage 206).
In addition, the ;Check Engine warning
lamp may light up (
Ypage 224).
For further information on warning and indicator
lamps in the instrument cluster, see
(
Ypage 224).
Problems with fuel and the fuel tank
ProblemPossible causes/consequences and MSolutions
Fuel is leaking from the
vehicle.The fuel line or the fuel tank is faulty.
GWARNING
Risk of explosion or fire.
XApply the electric parking brake.
XSwitch off the engine.
XRemove the SmartKey from the ignition lock.
or, in vehicles with KEYLESS-GO start-function or KEYLESS ‑GO
XOpen the driver's door.
The vehicle electronics are now in positiong.This is the same as
the SmartKey being removed from the ignition.
XDo not restart the engine under any circumstances.
XConsult aqualified specialist workshop.
The fuel filler flap cannot
be opened.The fuel filler flap is not unlocked.
XUnlock the vehicle (Ypage 70).
The SmartKey battery is discharged or nearly discharged.
XUnlock the vehicle using the mechanical key (Ypage 77).
The fuel filler flap is unlocked, but the opening mechanism is jammed.
XConsult aqualified specialist workshop.
140Refueling
Driving and parking

Parking
Important safety notes
GWARNING
Flammable material such as leaves, grass or
twigs may ignite if they come into contact with
hot parts of the exhaust system or exhaust
gas flow. There is arisk of fire.
Park the vehicle so that no flammable mate-
rials come into contact with parts of the vehi-
cle which are hot. Take particular care not to
park on dry grassland or harvested grain
fields.
GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking position P.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. There is arisk of
an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
!Always secure the vehicle correctly against
rolling away.O therwise, the vehicle or its driv-
etrain could be damaged.
To ensure that the vehicle is secured against
rolling away unintentionally:
Rthe electric parking brake must be applied.
Rthe transmission must be in position jand
the transmission position display must show
j in the multifunction display.
Rthe SmartKey must be removed from the igni-
tion lock.
Ron uphill or downhill gradients, the front
wheels must be turned towards the curb.
Switching off the engine
Important safety notes
GWARNING
The automatic transmission switches to neu-
tral position Nwhen you switch off the engine.
The vehicle may roll away.T here isarisk of an
accident.
After switching off the engine, always switch
to parking position P.Prevent the parked vehi-
cle from rolling away by applying the parking
brake.
Automatic transmission
XApply the electric parking brake.
XAll vehicles (except Mercedes-AMG vehi-
cles): shift the transmission to position j.
XMercedes-AMG vehicles:press button:.
XWith the SmartKey : turn the SmartKey to
position gin the ignition lock and remove it.
The immobilizer is activated.
XWith the Start/Stop button: press the
Start/Stop button (Ypage 122).
The engine stops and all the indicator lamps in
the instrumentc luster go out.
If the driver's door is closed, this is the same
as key position 1.Ifthe driver's door is open,
this is the same as key position g,i.e. the
SmartKey having been removed.
If you switch the engine off with the transmis-
sion in position korh,t he automatic trans-
mission shifts to iautomatically.
With the SmartKey: if you then open the driv-
er's door or the front-passenger door or remove
Parking141
Driving and parking
Z

the SmartKeyfromthe ignition, the automatic
transmission shifts to jautomatically.
With the Start/Stopb utton:if youtheno pen
the driver's door or the front-passenge rdoor,
the automatic transmission shifts to jauto-
matically.
If yo uwantthe automatic transmission to
remai ninneutral i,e.g.w henh avingt he vehi-
cle cleane dinanautomatic car wash with a
towing system:
XVehicle switht he Start-Stopb utton:
remove the Start-Stop button fromt he igni-
tio nlock.
XInsert the SmartKeyi nto the ignition lock.
XAllv eh icles: switch the ignition on.
XDepres sthe brake peda land kee pit
depressed.
XEngage neutral i.
XReleasethe brake pedal.
XReleas ethe electri cparking brake.
XSwitch off the ignition and leav ethe SmartKey
in the ignition lock.
Electric parking brake
General notes
GWARNING
If yo uleave children unsupervised in the vehi-
cle ,theyc ould setitinm otion by,for example:
Rrelease the parking brake.
Rshift the automatic transmission ou tofthe
parking position P.
Rstart the engine.
In addition, theym ayoperate vehicl eequip-
ment and become trapped .There is arisko f
an accident and injury.
When leaving the vehicle, always take the
SmartKeyw ithy ou and lock the vehicle. Never
leav echildren unsupervised in the vehicle. The functio
nofthe electric parking brake is
dependent on the on-board voltage. If the on-
boar dvoltag eislowor there is amalfunctio nin
the system, it mayn ot be possibletoapplythe
releasedp arking brake.
XIf thisist he case, onl yparkt he vehicl eon
level ground and secur eittoprevent it rolling
away.
XShift the automatic transmission to position
j.
It mayn ot be possibl etorelease an applied
parking brake if the on-board voltag eislowor
there is amalfunctio ninthe system. Contact a
qualified specialis tworkshop.
The electric parking brake performs afunction
tes tatr egular intervals whil ethe engine is
switched off .The sound sthatc an be he ar
dw hile
th

isiso ccurring ar enormal.
Applyin gorreleasing manually
XTo engage: push handle :.
When the electric parking brake is applied,
the red F(USA only) or !(Canada
only) indicator lamp lights up in the instru-
ment cluster.
Th ee lectric parking brake can also be applied
when the SmartKeyisr emoved.
XTo release:pull handle:.
The red F(USA only) or !(Canada
only) indicator lamp in the instrument cluster
goes out.
Th ee lectric parking brake can onl ybe
released:
Rif the SmartKeyisinp osition 1or2 in
the ignition lock (Ypage 122 )or
Rif the ignition wa sswitched on using the
Start/Stop button
142Parking
Driving an dparking

Drivingtips
General notes
Important safet ynotes
GWARNING
If you switch of fthe ignition whil edriving,
safety-relevant function sare only available
wit hlimitations, or no tatall. Thi scould affect,
fo re xample, th epowe rsteerin gand th ebrake
boostin geffect. You will require considerably
more effort to steer and brake .There is arisk
of an accident.
Do no tswitch of fthe ignition whil edriving.
GWARNING
If you operat emobile communication equip -
men twhen driving, you may be distracted
from th etraffic situation .You could also los e
contro lofthevehicle. There is ariskofa n
accident.
Only operat ethise quipmen twhen th evehicle
is stationary.
Observ ethe lega lrequirements fo rthe country
in whic hyou are driving. Some jurisdiction spro-
hibi tthe driver from usin gamobile phone whil e
drivin gavehicle.
If you mak eacallw hiled riving, always use
hands-free mode. Only operat ethe telephon e
when th etraffic situation permits. If you are
unsure ,pull over to asafel ocation and stop
befor eoperatin gthe telephone.
Bear in min dthatatas peed of only 30 mph
(approximately 50 km/h), th evehicle cover sa
distanc eof44f t(approximately 14 m)per sec-
ond.
Drive sensibly –save fuel
Observe the following tips to save fuel:
RThe tires should always be inflated to the rec-
ommended tire pressure.
RRemove unnecessary loads.
RRemove roof racksw hen they are not needed.
RWarm up the engineatlow engin espeeds.
RAvoid frequenta cceleration or braking.
RHave all maintenanc ework carried out as
indicated by the servicei ntervals in the Main- tenance Booklet or by the servicei
nterval dis-
play.
Fuel consumption also increases when driving in cold weather, in stop-start traffic and in hilly ter-
rain.
Drinking and driving
GWARNING
Drinkin gand driving and/or takin gdrugs and
driving are very dangerous combinations.
Even asmall amount of alcohol or drugs can
affect your reflexes, perceptions and judg-
ment.
The possibility of aserious or even fatal acci-
dent is greatly increased when you drink or
take drugs and drive.
Do not drink or take drugs and drive or allow
anyone to drive who has been drinking or tak-
ing drugs.
Emission control
GWARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There
is ar isk of fatal injury. Thereforen ever leave
the engin erunning in enclosed spaces with-
out sufficientv entilation.
Certain engin esystems are designed to keep
the level of poisonous component sinexhaust
fumes within legal limits.
These systems only work at peak efficiency if
they are serviced exactly in accordance with the
manufacturer's specifications .Always have
work on the engin ecarried out at aqualified
specialist workshop. Mercedes-Benz recom-
mends that you use an authorized Mercedes-
BenzC enter for this purpose. In particular, work
relevant to safety or on safety-related systems
must be carried out at aqualified specialist
workshop.
The engin esettings must not be changed under
any circumstances. Furthermore, all specific
servicew ork must be carried out at regular
intervals and in accordance with the Mercedes-
Benzs ervicer equirements. Details can be found
in the Maintenance Booklet.
144Driving tips
Driving and parking

In addition to driving style, the actual consump-
tion is affected by other factors, such as:
RLoad
RTire pressure
RCold start
RChoice of route
RActive electrical consumers
These factors are not includedint he ECO dis-
play.
An economical driving style specially requires
driving at moderate engine speeds.
Achieving ahigher valu einthe categories
"Acceleration" and "Constant":
Robserve the gearshift recommendations.
Rdrive the vehicle in drive program Cor E
(vehicles with aDYNAMIC SELECT button).
On long journeys at aconstant speed,e .g. on the
highway, only the outer area for "constant" will
change.
The ECO display summarizes the driving style
from the start of the journey to its completion.
Therefore, there are more marked changes in
the outer areasatt he start ofajourney. On lon-
ger journeys, there are fewer changes. For more
marked changes, perform amanua lrest
(
Ypage 181).
For more information on the ECO display, see
(
Ypage 180).
Braking
Important safety notes
GWARNING
If you shift down on aslippery road surface in
an attempt to increase the engine's braking
effect, the drive wheelsc ould lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on aslippery road surface.
Downhill gradients
!On long and steep gradients, you must
reduce the load on the brakes by shifting to a
lowerg ear in good time. This allows you to
take advantage of engine braking. For this you
must first activate manua lgearshifting. This helps you to avoid overheating the brakes and
wearing them out excessively.
When you take advantage of engine braking, it
is possible that
adrive wheel willn ot rotate for
some time, e.g. on aslippery road surface.
This could cause damage to the drive train.
This type of damage is not covered by the
Mercedes-Benz warranty.
Briefly depressing the accelerator pedalo n
downhill gradients whilet he manualdrive pro-
gram Mis temporarilya ctivated: the automatic
transmission may switch to the last active auto-
matic drive program Eor S.T he automatic trans-
missionm ay shift to ahigherg ear. This can
reduce the engine's braking effect.
Heavy and light loads
GWARNING
If you rest you rfoot on the brake pedalw hile
driving, the braking system can overheat. This increases the stopping distance and can even
cause the braking system to fail.T here is a
risk of an accident.
Never use the brake pedalasaf ootrest. Never
depresst he brake pedala nd the accelerator
pedalatt he same time.
!Depressing the brake pedalc onstantly
results in excessive and premature weart o
the brake pads.
If the brakes have been subjected to aheavy
load,don ot stop the vehicle immediately.D rive
on for ashort while. This allows the airflow to
cool the brakes more quickly.
Wet roads
If you have driven for along time in heavy rain
withoutb raking, there may be adelayed reac-
tion from the brakes when braking for the first
time. This may also occur after the vehicle has
been washed or driven through deep water.
You have to depresst he brake pedalmore
firmly.M aintainagreater distance from the
vehicle in front.
After driving on awet road or having the vehicle
washed, brake firmly whilep aying attention to
the traffic conditions. This willw arm up the
brake discs, thereby drying them more quickly
and protecting them against corrosion.
146Driving tips
Driving and parking

Limited braking performance on salt-
treated roads
If you driveonsalted roads,alayer of salt resi-
due may for monthebraked iscsand brake
pads. This can result in asignificantly longer
braking distance.
RIn ordertop revent any salt build-up, apply the
brakes occasionally while paying attention to th et raffic conditions.
RCarefully depress th ebrakep edal and the
beginnin gand end of ajou rney.
RMaintain agreater distanc etothevehicle
ahead.
Servicing th ebrakes
!The brakef luid level may be to olow, if:
Rif th ered brakew arning lamp lightsupi n
th ei nstrumentc luster and
Ryou hearawarning tone while th eengine is
running
Observe additional warning messages in the
multifunction display.
The brakef luid level may be to olow due to
brak epad wear or leaking brak elines.
Hav ethe brakes ystem checked immediately.
Consult aqualifie dspecialist workshop to
arrange this.
!Af unction or performanc etests hould only
be carried out on a2-axle dynamometer. If
you wish to operate th evehicle on such a
dynamometer, please consult aqualifie dspe-
cialis tworkshop in advance. You could oth-
erwis edamage th edrivet rain or th ebrake
system.
!As th eESP®system operates automatically,
th ee ngine and th eignitio nmust be switched
off (th eSmartKey must be in position uor
1 in th eignitio nlock), if th eelectric parking
brakeist ested onabraking dynamometer
(maximum 10 seconds).
Brakin gtriggered automatically by ESP
®may
cause severe damage to th ebrakes ystem.
All check sand maintenanc ework on th ebrake
system must be carried out at aqualifie dspe-
cialis tworkshop.
Hav ebrakep ads installe dand brakef luid
replaced at aqualifie dspecialist workshop. If th
ebrakes ystem has onl ybeen subject to
moderatel oads, you should tes tthe functional-
ity of your brakes at regular intervals.
You can fin dadescription of Brake Assist (BAS
)
on (Ypage 61).
Mercedes-Ben zrecommend stha tyou onl yhave
brak epads/linings installe donyour vehicle
whichh ave been approved for Mercedes-Benz
vehicle sorwhichcorrespondtoane quivalent
qualitys tandard. Brake pads/linings whichh ave
not been approved for Mercedes-Ben zvehicles
or whicha re not of an equivalent qualityc ould
affect your vehicle's operatin gsafety.
Mercedes-Ben zrecommend sthaty ou onl yuse
brakef luid that has been specially approved for
your vehicle by Mercedes-Benz, or whichc orre-
sponds to an equivalent qualitys tandard. Brake
fluid whichh as not been approved for
Mercedes-Ben zvehicle sorw hichisn ot of an
equivalent qualityc ould affect your vehicle's
operatin gsafety.
Checkingb rake lining thickness
You can measure th ebreak pad/linin gthick-
nes susingat estg age. Color-coding( green or
red) on th etestg age allows you to determine
whether th ebrakep ad/linin gthicknes sisstill
sufficient .The tes tgage is in th evehicle docu-
mentw allet in th egloveb ox.
Front wheel
Driving tips147
Driving and parking
Z

Rear wheel
XBring thevehicl eand wheels int oasuitable
position so that you can attach test gage A.
XSecurethe vehicl eagainst rollin gaway
(Ypage 141).
XEngage park position P.
XSwitchoff th eengine.
XPlac etestg age Abetween th ewheel's
spoke sonb rakepad/lining =.
XHold test gage Averticall yonb rak edisc :
and slid emeasurin gpin; onto brak e
disc :.
XChec kwhichc olor field ?thea rrow on
measurin gpin; is pointing to .
Green: theb rak epad/lining thickness is suf -
ficient.
Red :th eb rak epad/lining thickness is no t
sufficient. Hav ethe brak epads/lining
checke dataq ualified specialist workshop.
To avoi daninaccurat emeasurement:
Rmak esurey ou position th ewheels suitably
Rdo no tput th emeasurin gpin on arecess in
th eb rak edisc
Driving on wet roads
Hydroplaning
If water has accumulated to acertai ndept hon
th er oad surface, there is adanger of hydro-
planing occurring, eve nif:
Ryou driv eatlow speeds
Rthet ires hav eadequat etread dept h
Fo rthisr eason ,intheevent of heav yrain or in
condition sinwhichh ydroplaning may occur ,
you mus tdriveint hefollowin gmanner:
Rlower your spee d
Ravoidruts
Ravoi dsudde nsteering movement s
Rbrakecarefully
Driving on flooded roads
!Do no tdrivet hroug hflooded areas .Chec k
th ed ept hofa ny water before driving throug h
it .D rive slowly throug hstanding water. Oth-
erwise, water may ente rthe vehicl einterior or
th ee nginec om partment. This can damag e
th ee lectronic component sintheengin eor
th ea utomatic transmission .Water can also
be drawn in by th eengine's air suction nozzles
and this can caus eengined amage.
Winter driving
GWARNIN G
If you shif tdown on aslipper yroad surfac ein
an attemp ttoincreas ethe engine's braking
effect, th edrivew heels could lose their grip.
There is an increased danger of skiddin gand
accidents .
Do no tshif td own for additional engin ebrak -
ing on aslipper yroad surface.
GDANGER
If th eexhaust pipe is blocke doradequat e
ventilation is no tpossible, poisonous gase s
suc hasc arbon monoxide (CO) may ente rthe
vehicle. This is th ecase, e.g. if th evehicl e
become strapped in snow. There is arisko f
fatal injury.
148Driving tips
Driving and parking