engine MERCEDES-BENZ CLA COUPE 2021 Workshop Manual

&
W
WARNI NG
ARNI NGRisk of /re and injury from
engine oil
If engine oil comes into contact with hot com-
ponent parts in the engine compartment, it
may ignite. #
Make sure that no engine oil is spilled
next tothe /ller opening. #
Allow the engine tocool o. and thor-
oughly clean the engine oil from compo-
nent parts before starting theve hicle. *
N
NOOTE
TE Engine damage caused byan inco r-
re ct oil /lter, incor rect oil or additi ves #
Do not use engine oils or oil /lters which
do not cor respond tothe speci/cations
ex plicitly prescribed forth e service inter-
va ls. #
Follow the inst ructions on the service
inter val display forch anging the engine
oil and obser vethe prescribed change
inter vals. #
Do not use additives. *
N
NOOTE
TE Damage caused bytopping up too
much engine oil To
o much engine oil can damage the engine or
th e catalytic con verter. #
Have excess engine oil remo ved at a
qu ali/ed specialist workshop. %
Depending on driving st yle, theve hicle con-
sumes up to0.8 litre of oil per 1000 km. The
oil consum ption may be higher than this when
th eve hicle is new or if you frequently drive at
high engine speeds. #
Turn cap 1anti-clockwise and remo veit. #
Top up the engine oil. #
Replace cap 1and turn it clockwise until it
engages. #
Check the oil le vel again (/ page 331). 332
332
Maintenance and care

Chec
Chec
king t
king t he coolant lev
he coolant lev el
el &
W
W ARNING
ARNING Risk of burns from hot compo-
nent parts in the engine compartment
Cer tain component parts in the engine com-
partment can be very hot, e.g. the engine, the
cooler and parts of theex haust system. #
Allow the engine tocool down and only
to uch component parts described in the
fo llowing. &
W
W ARNING
ARNING Risk of scalding from hot cool-
ant
If yo u open the cap, you could be scalded. #
Let the mo tor cool down before opening
th e cap. #
When opening the cap, wear pr otective
glo ves and saf ety glasses. #
Open the cap slo wlytorelease pressure. #
Park theve hicle on a le vel sur face. #
Check the coolant temp erature display in the
inst rument cluster.
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.
% Further information on coolant (/ page 395) T
T
opping up t
opping up t he windscr
he windscreen w
een washer syst
asher syst em
em &
W
WARNING
ARNING Risk of burns from hot compo-
nent parts in the engine compartment
Cer tain component parts in the engine com-
partment can be very hot, e.g. the engine, the
cooler and parts of theex haust system. #
Allow the engine tocool down and only
to uch component parts described in the
fo llowing. Maintenance and care
333
333

&
W
WARNI NG
ARNI NG‑ Risk of /re and injury due to
windscreen washer concent rate
Wi ndsc reen washer concent rate is highly 0am-
mable. It could ignite if it comes into contact
with hot engine component parts or the
ex haust system. #
Make sure that no windscreen washer
concent rate spills out next tothe /ller
opening. #
Remo vecap 1bytheta b. #
Top up thewa sher 0uid.
% Further information about the windscreen
wa sher 0uid (/ page 396) K K
eeping t
eeping t he air
he air-w
-wat
ater duct fr
er duct fr ee
ee #
Keep the area between the bonnet and the
windscreen free of deposits, e.g. ice, snow
and lea ves. Cleaning and care
Cleaning and care
Inf
Inf
or
ormation on w
mation on w ashing t
ashing the v
he vehicle in a car w
ehicle in a car w ash
ash &
W
WARNING
ARNING Risk of an accident due to
re duced braking po wer aTer washing the
ve hicle
Braking e1ciency is reduced aTer washing the
ve hicle. #
ATer theve hicle has been washed, brake
carefully while paying attention tothe
tra1c conditions until braking po wer has
been fully restored. 334
334
Maintenance and ca
re

R
The air conditioning system is set toair-recir-
culation mode.
R Parking Assist PARKTRONIC is deactivated.
R V
Vehicles wit
ehicles wit h 360° Camer
h 360° Camer a:
a:The front ima geis
activated aTer appr ox. eight seconds.
If one of the settings cannot be selected, this is
displa yedby a% behind there specti veset-
ting.
Ab ove a speed of 20 km/h car wash mode is
automatically deacti vated.
The following settings are reset when car wash
mode is deacti vated:
R The outside mir rors are folded out.
R The rain sensor is activated.
R The rear wind owwiper is activated.
R The air conditioning system is set tofresh air
mode.
R Parking Assist PARKTRONIC is reset tothe
pr ev iously selected setting.
R The windo wsand the sliding sunroof remain
closed. R
V Vehicles wit
ehicles wit h 360° Camer
h 360° Camer a:
a:The front image is
deactivated at speeds abo ve18 km/h. A
A
ctiv
ctiv ating/deactiv
ating/deactiv ating aut
ating automatic car w
omatic car w ash mode
ash mode R
R
eq
eq uir
uir ements:
ements:
R theve hicle is stationar y.
R the engine is running.
Multimedia system: 4 © 5
Settings 5
Quick access
A
A ctiv
ctiv ating aut
ating aut omatic car w
omatic car w ash mode
ash mode #
Select Car wash mode . #
Select Start.
If one of the settings cannot be selected, this is
displa yedby a% behind there specti veset-
ting.
% For an overview of the settings made when
activating automatic car wash mode
(/ page 334). Deactiv Deactiv
ating aut
ating aut omatic car w
omatic car w ash mode
ash mode #
Select Stop.
The automatic car wash settings are reset.
% The automatic car wash mode is automatically
deacti vated as soon as a speed of 20 km/h is
ex ceeded. Inf
Inf
or
ormation on using a high-pr
mation on using a high-pr essur
essure cleaner
e cleaner &
W WARNING
ARNING Risk of an accident when using
high-pressure cleane rswith round-spr ay
nozzles
The water jet can cause extern ally invisible
damage.
Components damaged in this wa y may un ex-
pectedly fail. #
Do not use a high-pressure cleaner with
round-spr aynozzles. #
Have damaged tyres or chassis parts
re placed immediatel y.336 336
Maintenance and care

To
avo id damage toyour vehicle, obser vethefo l-
lowing when using a high-pressure cleaner:
R The key is at a minimum dis tance of 3 m away
from theve hicle. Otherwise the boot lid could
open unintentionall y.
R Maintain a distance of at least 30 cm tothe
ve hicle.
R V
Vehicles wit
ehicles with decor h decorativ
ative f
e foil:
oil: Parts of your
ve hicle are co vered with a decorative foil.
Maintain a distance of at least 70 cm between
th efo il-co vered parts of theve hicle and the
nozzle of the high-pressure cleaner. Mo vethe
high-pressure cleaner nozzle around whilst
cleaning. The waterte mp erature of the high-
pressure cleaner must not exceed 60°C.
R Obser vethe information on the cor rect dis-
ta nce in the equipment manufacturer's oper-
ating inst ructions.
R Do not direct the nozzle of the high-pressure
cleaner directly at sensitive parts, such as
tyres, gaps, electrical components, batteries,
light sources and ventilation slits. W W
ashing t
ashing t he v
he vehicle b
ehicle b y hand
y hand *
N
NOOTE
TE Engine damage due towa ter ing ress #
Take care not topoint thewa ter jet
directly towa rdsth e air inlet grille below
th e bonnet. obser
vethe legal requ irements, e.g. in a number
of countries, washing byhand is only permitted in
special lydesignated wash ba ys. #
Use a mild cleaning agent, e.g. car shampoo. #
Washtheve hicle with luk ewarm water using a
soT car sponge. When doing so, do not
ex pose theve hicle todirect sunlight. #
Carefully hose theve hicle o. with water and
dry using a chamois.
% Obser vethe no tes on the care of car parts
(/ page 339). N
No
ot
tes on paintw
es on paintw or
ork/matt
k/matt /nish
/nishpaintw
paintw or
ork care
k care To
avo id damaging the paintwork and inter fering
with the driving assistance systems, please
obser vethefo llowing no tes: P
P
aint
aint
R Insect remains: soak with insect remo ver and
ri nse o. the treated areas aTer wards.
R Bird droppings: soak with water and rinse o.
aTer wards.
R Tree resin, oils, fuels and greases: remo veby
ru bbing gently with a clo thsoaked in petro-
leum ether or lighter 0uid.
R Coolant and brake 0uid: remo vewith a damp
clo thand clean water.
R Tar stains: use tarre mo ver.
R Wax: use silicone remo ver.
R Do not attach sti ckers, /lms or similar materi-
als. Only ha ve/lm attached tothe bumper at
a quali/ed specialist workshop.
R Remo vedirt immediatel y,where possible.
Matt
Matt /nish
/nish
R Only use care products appr ovedfor
Mercedes-Benz.
R Do not attach stic kers, /lms or similar materi-
als. Only ha ve/lm attached tothe bumper at
a qu ali/ed specialist workshop. Main
tenance and ca re
337
337

R
Do not polish theve hicle and light-alloy
wheels.
R Only use car washes that cor respond tothe
latest engineering standards.
R Do not use car wash prog rammes with a /nal
hot wax treatment.
R Do not use paint cleaners, bu1ng or polishing
products, gloss preser vers, e.g. wax.
In theev ent of paintwork damage:
R Always ha vepaintwork repairs car ried out at a
qu ali/ed specialist workshop.
R Make sure thera dar sensors function
(/ page 214). N
No
ot
tes on cleaning decor
es on cleaning decor ativ
ative f
e foils
oils Obser
vethe no tes on matt /nish care in thech ap-
te r "No tes on paintwork/matt /nish paintwork
care" (/ page 337). They also apply tomatt dec-
orative foils.
Obser vethe no tes on cleaning decorative foils to
av oid vehicle damage. Cleaning
Cleaning
R For cleaning, use plenty of water and a mild
cleaning agent without additives or abrasive
substances, e.g. a car shampoo appr ovedfor
Mercedes-Benz.
R Remo vedirt immediatel y,where possible,
whilst avoiding rubbing too hard. There is oth-
erwise a risk of damaging the decorative foil
ir re parabl y.
R Ifth ere is dirt on the /nish or if the decorative
fo il is dull: Use thePa int Cleaner recommen-
ded and appr ovedfo r Mercedes-Benz.
R Insect remains: Soak with insect remo ver and
ri nse o. the treated areas aTer wards.
R Bird droppings: Soak with water and rinse o.
aTer wards.
R Topreve ntwa ter stains, dry a foil-wrapped
ve hicle with a soT, absorbent clo thaTer every
car wash.
Av
Av oiding damag
oiding damag e t
e to t
o t he decor
he decor ativ
ative f
e foil
oil
R The service life and colouring of decorative
foils are impaired by:
- Sunlight -
Tempe rature, e.g. hot air blo wer
- Weather conditions
- Stone chippings and dirt
- Chemical cleaning agents
- Oily products
R Do not use polish on matt decorative foil. Po l-
ishing will ha vethe e.ect of shining thefo il-
wrapped sur face.
R Do not treat matt or st ructured decorative
fo ils with wax.Pe rm anent stains may occur.
Scratches, cor rosive deposits, areas a.ected by
cor rosion and damage caused byincor rect care
cannot alw ays be comple tely re paired. In such
cases, visit a quali/ed specialist workshop.
Yo u can obtain more information on care and
cleaning products from the manufacturer.
In the case of foil-wrapped sur faces, optical di.er-
ences may occur between the sur faces that we re
not pro tected bya decorative foil aTer removing a
decorative foil. 338 338
Maintenance and care

If
yo u ha vetodisconnect the 12 V batter y,con-
ta ct a quali/ed specialist workshop.
Comply with saf ety no tes and take protective
measures when handling batteries. Risk of
explosion. Fire
, naked 0ames and smoking are
prohibi ted when handling the batter y.
Av oid creating spar ks. Electrolyte or battery acid is cor
rosive.
Av oid contact with the skin, eyes or
clo thing. Wear suitable pr otective
clo thing, in particular glo ves, an apron
and a face mask. Immediately rinse
electrolyte or acid splashes o. with
clean water. Consult a doctor if neces-
sar y. We
ar saf ety glasses. Ke
ep children away. Obser
vethis Owner's Manual.
Obser vethefo llowing if you do not intend touse
th eve hicle over an extended period of time:
R Activate standby mode.
R Alternativel y:connect the battery toa battery
ch arge r appr ovedby Mercedes-Benz or con-
sult a quali/ed specialist workshop todiscon-
nect the batter y. N N
o
ot
tes on st
es on st ar
arting assist
ting assist ance and c
ance and c har
harging t
ging t he 12
he 12
V batt
V batt ery
ery All v All v
ehicles
ehicles
When charging the battery and during starting
assistance, alw ays use the jump-start connection
point in the engine compartment. *
N
NOOTE
TE Damage tothe battery from over-
vo ltage When
charging using a battery charge r without
a re striction of the maximum charging voltage,
th e battery or the on-board electronics can be
damaged. #
Only use battery charge rs with a maxi-
mum charging voltage of 14.8 V. &
W
WARNI NG
ARNI NGRisk of explosion due tohydro-
ge nga s igniting
If, when charging a batter y,there is a short
circuit or spar ksstart toform ,th ere is a dan-
ge r of hydrogen gas igniting. #
Take care that the positive clamp con-
nected toa battery does not come into
contact with vehicle parts. #
Never place me tal objects or tools on a
batter y. #
When connecting and disconnecting the
batter y,alw ays obser vethe sequence of
battery clamps described. 352
352
Breakdown assistance

#
Take care toonly connect battery term i-
nals of identical polarity when receiving
starting assistance. #
Obser vethe sequence described for
connecting and disconnecting the jump
leads when receiving starting assistance. #
Do not connect or disconnect the bat-
te ry term inals while the engine is run-
ning. &
W
W ARNI NG
ARNI NGRisk of explosion due toexplo-
sive mixture of gases
An explosive mixture of gases can escape
from the battery during charging and starting
assis tance. #
Fire , naked 0ames, smoking and creating
spar ksmust be avoided. #
Make sure there is adequate ventilation. #
Do not stand overth e batter y. &
W
WARNI NG
ARNI NGRisk of explosion from a frozen
battery
A dischar ged battery may freeze at temp era-
tures slightly abo veor below freezing point.
During starting assistance or battery charging,
battery gas can be released. #
Always allow a battery tothaw before
ch arging it or per form ing starting assis-
ta nce. If
th e indicator/warning lamps in the inst rument
clus ter do not light up at low temp eratures, it is
ve ry likely that the dischar ged battery has frozen.
In this case you may neither jump-start theve hi-
cle nor charge the batter y.
The service life of a bat tery that has been thawed
may be dramatically shor tened. The starting char-
acteristics may be impaired, especially at low
te mp eratures.
It is recommended that you ha veath awe d battery
ch ecked at a quali/ed specialist workshop. Plug-in h
Plug-in h ybr
ybrid
id
If yo ur vehicle has been star ted with starting
assistance, it may not be possible touse the elec-
tric drive for appr oximately 30 minutes.
St arting assis tance is not considered tobe a nor-
mal operating condition.
All v All v ehicles
ehicles
* NO
NOTE
TEDamage caused bynume rous or
ex tended attem ptsto start the engine Numerous or
extended attem ptsto start the
engine may damage the catalytic con verter
due tonon-combusted fuel. #
Avoid numerous and extended attem pts
to start the engine. Obser
vethefo llowing points during starting assis-
ta nce and when charging the batter y:
R Only use undamaged jump lead/charging
cables with a su1cient cross-section and
insulated term inal clamps.
R Non-insulated parts of thete rm inal clamps
must not come into contact with other me tal Breakd
own assistance
353 353

parts while
the jump lead/charging cable is
connected tothe battery/jump-start connec-
tion point.
R The jump lead/charging cable must not come
into contact with any parts which may mo ve
when the engine is running.
R Always make sure that nei ther you nor the bat-
te ry is electrostatically charge d.
R Keep awa y from /re and naked 0ames.
R Do not lean over the batter y.
Obser vethe additional following points when
ch arging the batter y:
R Only use battery charge rs tested and
appro vedfo r Mercedes-Benz.
R Read the battery charge r's operating inst ruc-
tions before charging the batter y.
Obser vethe additional following points during
starting assistance:
R Starting assis tance may only be pr ovided
using vehicles, batteries or other jump start
devices with a nominal voltage of 12 V.
R The vehicles must not touch. R
V Vehicles wit ehicles wit h a pe
h a petr
trol engine:
ol engine: jump-start the
ve hicle only when the engine and exhaust sys-
te m are cold. S
S
t
tar
ar ting assist
ting assist ance and c
ance and c har
harging t
ging t he 12 V batt
he 12 V batt ery
ery R
R
eq
eq uir
uir ements:
ements:
R The vehicle is secured with the electric par k-
ing brake.
R V
V ehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: the
transmission is in position j.
R V
Vehicles wit
ehicles wit h manual tr
h manual tr ansmission:
ansmission: the trans-
mission is in neutral.
R The vehicle and all elect rical consume rsare
switched o..
R The bonnet is open. Example: engine compartment
#
Slide co ver1 of POSITIVE contact 2onthe
jump-starting connection point in the direction
of the ar row. #
Connect POSITIVE contact 2onyour vehicle
to the positive term inal of the donor battery
using the jump lead/charging cable. Alw ays354
354
Breakdown assistance

begin with POSITIVE contact
2onyour own
ve hicle /rst. #
Dur
During st
ing st ar
arting assist
ting assist ance:
ance:startthe engine of
th e donor vehicle and run at idle speed. #
Connect the negative term inal of the donor
battery and ear thpoint 3ofyour ow nve hicle
by using the jump lead/charging cable. Begin
with the donor battery /rst. #
Dur
During st
ing st ar
arting assist
ting assist ance:
ance:startthe engine of
yo ur ow nve hicle. #
Dur
During t
ing t he c
he char
harging pr
ging pr ocess:
ocess: startthech arg-
ing process. #
Dur
During st
ing st ar
arting assist
ting assist ance:
ance:letthe engines run
fo r se veral minutes. #
Dur
During st
ing st ar
arting assist
ting assist ance:
ance:before disconnect-
ing the jump lead, switch on an electrical con-
sumer on your ow nve hicle, e.g. there ar win-
dow heater or lighting.
When the starting assistance/charging process is
comple te, per form thefo llowing steps: #
Firs t, re mo vethe jump lead/charging cable
from ear thpoint 3and the negative term inal of
the donor batter y,then POSITIVE contact
2 and the positive term inal of the donor bat-
te ry. Begin each time with the contacts on
yo ur ow nve hicle /rst. #
ATer removing the jump lead/charging cable,
close co ver1 of POSITIVE contact 2.
Plug-in h
Plug-in h ybr
ybrid:
id:ifyo ur vehicle has been star ted
with starting assis tance, it may not be possible to
use the electric drive for appr oximately 30
minutes.
Fu rther information can be obtained at a quali/ed
specialist workshop. R R
eplacing t
eplacing t he 12 V batt
he 12 V batt ery
ery #
Obser vethe no tes on the 12 V battery
(/ page 350).
Mercedes-Benz recommends that you ha vethe
12 V battery replaced at a quali/ed specialist
wo rkshop, e.g. at a Mercedes-Benz Se rvice
Centre. Obser
vethefo llowing no tes if youwa nttoreplace
th e battery yourself:
R Alwaysre place a faulty battery with a battery
which meets the speci/c vehicle requ ire-
ments.
The vehicle is equipped with an AGMtech nol-
ogy bat tery (Absorbent Glass Mat) or a lith-
ium-ion batter y.Fu llve hicle functionality is
only guaranteed with an AGM bat tery or lith-
ium-ion batter y.Fo r saf etyre asons, Mercedes-
Benz recommends that you only use batteries
which ha vebeen tested and appro vedfo ryo ur
ve hicle byMercedes-Benz.
R Carryove r de tach able parts, such as vent
hoses, elbow /ttings or term inal co vers from
th e battery being replaced.
R Make sure that theve nt hose is alw ays con-
nected tothe original opening on the side of
th e batter y.
Fi t any existing or supplied cell caps.
Otherwise, gases or battery acid could
escape.
R Make sure that de tach able parts are recon-
nected in the same way. Breakd
own assistance
355 355