engine MERCEDES-BENZ CLA COUPE 2019 Repair Manual

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
th efo 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 521). 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
451

#
Allow the engine tocool down and only
to uch co mponent parts described in
th efo llowing. &
WARNING Danger of bu rns when open‐
ing 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 with hot gases or other escaping
operating fluids. #
Before opening the bonn et, allow the
engine tocool down. #
Intheeve nt of a fire inthe engine com‐
partment, keep the engine bonn et
closed and call thefire service. &
WARNING ‑ Risk of fire and injury due to
windscreen washer concentrate
Wi ndsc reen washer concentrate is highly
fl ammable. It could ignite if it comes into
con tact wi thhot engine component parts or
th eex haust sy stem. #
Make sure that no windsc reen washer
concentrate spills out next tothefiller
opening. #
Remo vethe cap 1bytheta b. #
Top up thewa sher fluid. Ke
eping the air-water duct free #
Keep the area between the bonn etand the
windscreen free of deposits, e.g. ice, sn ow
and lea ves. Cleaning and care
Information on
washing theve hicle in a car
wa sh &
WARNING Risk of an accident due to
re duced braking po wer af terwa shing the
ve hicle
Braking ef ficiency is reduced af terwa shing
th eve hicle. #
Afterth eve hicle has been washed,
brake carefully while paying attention to
th e traf fic conditions until braking
po we r has been fully restored. 452
Maintenance and care

*
NO
TEDama gedue tounsuitable car
wa sh #
Before driving into a car wash make
sure that the car wash is suitable for
th eve hicle dimensions. #
Ensure there is suf ficient ground clear‐
ance between the underbody and the
guide rails of the car wash. #
Ensure that the clearance width of the
car wash, in particular the width of the
guide rails, is suf ficient. To
avo id damage to yourvehicle when using a
car wash, ensure thefo llowing beforehand:
R Active Dis tance Assi stDISTRONIC and the
HOLD function are deactivated.
R the 360° Camera or there ve rsing camera is
switched off.
R the side windo wsand sliding sun roof are
comple tely closed.
R the blo werfo rth eve ntilation/heating is
switched off. R
the windscreen wiper switch is in position
g.
R in car washes with a con veyo r sy stem: neu‐
tral iis engaged.
R theke y is at a minimum dis tance of 3 m
aw ay from theve hicle, otherwise the boot lid
could open unintentionally.
% Ifyo uwo uld like tolea vetheve hicle while it
is being washed, make sure theke y is loca‐
te d in theve hicle. The jgear is otherwise
automatically engaged.
% If, af terth e car wash, youre mo vethewax
from the windscreen and wiper rubbers, this
will pr event smearing and reduce wiper
noise. Ac
tivating/deactivating automatic car wash
mode Re
quirements:
R theve hicle is stationary
R the engine is running. Multimedia sy
stem:
4 © 5
Settings
5 Schnellzugriff (Quick access)
Ac tivating automatic car wash mode #
Select Automatic car wash mode. #
Select Start.
If one of the settings cann otbe selected, this is
displa yedby a% behind there spective set‐
ting.
% For an overview of the settings made when
activating automatic car wash mode
(/ page 452).
Deactivating automatic car wash mode #
Select Stop.
The automatic car wash settings are reset.
% The automatic car wash mode is automati‐
cally deactivated as soon as a speed of
10 km/h is exceeded. Maintenance and care
453

specialist wo
rkshop or toa collection
point for used batteries. If
yo u ha vetodisconnect the12 V batter y,con‐
ta ct a qualified specialist workshop.
Comply with saf ety no tes and take protective
measures when handling batteries. Risk of
explosion. Fire, naked
flames and smoking are
prohibi ted when handling the batter y.
Av oid creating spar ks. Electrolyte
or battery acid is cor ro‐
sive. Avoid contact with the skin, eyes
or clo thing. Wear suitable pr otective
clo thing, in particular glove s, an
apron and a face mas k.Immedia tely
ri nse electrolyte or acid splashes off
with clean water.Consult a doc tor if
necessar y. We
ar saf etygl asses. Ke
ep children away. Obser
vethis Owner's Manual.
Obser vethefo llowing if you do not intend touse
th eve hicle over an extended pe riod of time:
R Activate standby mode.
R Alternatively: connect the battery toa bat‐
te ry charge r appro vedby Mercedes-Benz or
consult a qualified specialist workshop to
disconnect the batter y. Note
s onstarting assi stance and on charg‐
ing the12 V battery Ve
hicles with a lithium-ion battery
When charging the battery and during starting
assis tance, al ways use the jump-s tart connec‐
tion point in the engine compartment.
* NO
TEDama getothe battery from over‐
vo ltage When
charging using a bat tery charge r with‐
out a maximum charging voltage, the battery
or the on-board electronics may be damaged. #
Only use battery charge rs with a maxi‐
mum charging voltage of 14.4 V. All
other vehicles
When charging the battery and during starting
assis tance, al ways use the jump-s tart connec‐
tion point in the engine compartment. 472
Breakdown assis tance

*
NO
TEDamaging the battery thro ugh
ove rvoltage When using a battery
charge r without a maxi‐
mum charging voltage, the battery or the
ve hicle electronics may be damaged. #
Only use battery charge rs with a maxi‐
mum charging voltage of 14.8 V. &
WARNING Risk ofexplosion from hydro‐
ge nga s igniting
A battery generates hydrogen gas during the
ch arging process. If there is a short circuit or
spar ksstart toform ,th ere is a danger of the
hy drogen gas igniting. #
Make sure that the positive term inal of
th e connected battery does not come
into conta ct withvehicle parts. #
Never place me tal objects or tools on a
batter y. #
When connecting and disconnecting the
batter y,yo u must obse rveth e descri‐
bed order forth e battery clamps. #
When giving starting assis tance, al ways
make sure that you on lyconnect bat‐
te ry term inals with identical polarity. #
During starting assis tance, you must
obse rveth e described order for con‐
necting and disconnecting the jump
lead. #
Do not connect or disconnect the bat‐
te ry cla mp s while the engine is running. &
WARNING Risk ofexplosion during
ch arging process and starting assis tance
During thech arging process and starting
assis tance, the battery may release an explo‐
sive gas mixture. #
Avoid fire , naked flames, creating
spar ksand smoking. #
Make sure that there is suf ficient venti‐
lation du ring thech arging process and
during starting assis tance. #
Do not lean over a batter y. &
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. Breakdown assis
tance 473

All
vehicles
* 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 only be pr ovided
using batteries with a nominal voltage of
12 V.
R The vehicles must not touch.
R Petrol engine: only acceptstarting assis‐
ta nce if the engine and exhaust sy stem are
cold. St
arting assi stance and charging the12 V
battery Re
quirements:
R The vehicle is secured with the electric park‐
ing brake.
R Vehicles with automatic transmission: the
transmission is in position j.
R Vehicles with manual transmission: the
transmission is in neutral.
R The ignition and all electrical consumers are
switched off.
R The bonnet is open. 474
Breakdown assis tance

#
Slide co ver1 of positive clamp 2onthe
jump-s tarting connection point in the direc‐
tion of the ar row. #
Connect positive clamp 2onyour vehicle to
th e positive pole of the donor battery using
th e jump lead/charging cable. Alw ays begin
with positive clamp 2onyour ow nve hicle
fi rs t. #
During starting assi stance: start the
engine of the donor vehicle and run at idle
speed. #
Connect the negative pole of the donor bat‐
te ry and ear thpoint 3ofyour ow nve hicle
by using the jump lead/charging cable. Begin
with the donor battery firs t. #
During starting assi stance: start the
engine of your ow nve hicle. #
During thech arging process: start the
ch arging process. #
During starting assi stance: letthe engines
ru nfo r se veral minutes. #
During starting assi stance: before discon‐
necting the jump lead, switch on an electrical
consumer in your ow nve hicle, e.g. there ar
wind owheater or lighting.
When thest arting assis tance/charging process
is compl ete, per form thefo llowing steps: #
First,re mo vethe jump lead/charging cable
from ear thpoint 3and the negative pole of
th e donor batter y,then from positive clamp
2 and the positive pole of the donor bat‐ te
ry. Begin ea chtime wi th the conta cts on
yo ur ow nve hicle firs t. #
Afterre moving the jump lead/charging
cable, close co ver1 of positive clamp 2.
Fu rther information can be obtained at a quali‐
fi ed specialist workshop. Re
placing the 12V battery #
Obser vethe no tes on the12 V battery
(/ page 470).
Me rcedes-Benz recommends that you ha vethe
12 V battery replaced at a qualified specialist
wo rkshop, e.g. at a Mercedes-Benz Service
Centre.
Obser vethefo llowing no tes if youwa ntto
re place the battery yourself:
R Alw aysre place a faulty bat tery with a battery
which meets the specific vehicle require‐
ments.
The vehicle is equipped with an AGMtech nol‐
ogy battery (Absorbent Glass Mat) or a li th‐
ium-ion batter y.Fu llve hicle functionality is Breakdown assis
tance 475

Pe
rm itted towing me thods Ve
hicle equipment/ towing
me thod Bo
th axles on thegr ound Fr
ont axle raised Re
ar axle raised
Ve hicles with manual transmission Yes, maximum 50 km at 50 km/h Yes, maximum 50 km at 50 km/h Yes, maximum 50 km at 50 km/h
Ve hicles with automatic transmis‐
sion Ye
s, maximum 50 km at 50 km/h Yes, maximum 50 km at 50 km/h Yes, maximum 50 km at 50 km/h if
th esteering wheel is fixe d in the
centre position wi thast eering
wheel lock
4MATIC vehicles Yes, maximum 50 km at 50 km/h No NoTo
wing with a raised axle: towing should be
per form ed byato wing compan y. To
wing theve hicle with bo thaxles on the
gr ound #
Obser vethe no tes on the permitted towing
me thods (/ page476). #
Makesure that the battery is connected and
ch arge d.
Obser vethefo llowing points when the battery is
dischar ged:
R the engine cann otbe star ted
R the electric parking brake cann otbe released
or applied R
vehicles with automatic transmission: the
automatic transmission cannot be shif tedto
position iorj. Breakdown assis
tance 477

Installing
theto wing eye #
Press the mark on co ver1 inwa rds and
re mo ve. #
Screw intheto wing eyeclockwise as far as it
will go and tighten.
Ve hicles with a trailer hitch: vehicles with a
trailer hitch do not ha veare ar brac ketfo rthe to
wing eye. Fasten theto w bar tothe trailer
hitch.
% Make sure that co ver1 engages in the
bumper when youre mo vetheto wing eye.
* NO
TEDama gedue toincor rect use of
th eto wing eye When a
towing eye is used toreco ver a vehi‐
cle, theve hicle may be damaged in the proc‐
ess. #
Only use theto wing eyeto to waw ay or
to w start theve hicle. To
w starting theve hicle (eme rgency engine
st art) Ve
hicles with automatic transmission
* NO
TEDama getothe automatic trans‐
mission due to tow-starting The automatic transmission may be damaged
in the process of tow- starting vehicles with
automatic transmission. #
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 477). #
Ifnecessa ry, 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. Breakdown assis
tance 481

#
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 482).
* 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. If
th e newly inser ted fuse also blo ws, ha vethe
cause traced and rectified at a qualified special‐
ist workshop.
Ensure thefo llowing before replacing a fuse:
R The vehicle is secured against rolling away.
R All electrical consumers are switched off.
R The ignition is switched off.
The electrical fuses are located in various fuse
bo xes:
R Fuse box in the engine compartment on the
left-hand side of theve hicle, when vie wed in
th e direction of tr avel (/ page 482)
R Fuse box in the front passenger foot we ll
(/ page 483)
R Fuse box in the cent reofthe boot
(/ page 484) Opening and closing
the fuse box in the
engine compa rtment Requ
irements:
R A dry clo thand a sc rewdriver are available. 482
Breakdown assis tance