engine MERCEDES-BENZ E-CLASS CABRIOLET 2020 Workshop Manual

ASS
YST PLUS se rvice inter val display Fu
nction of the ASS YST PLUS se rvice inter val
displ ay The ASS
YST PLUS service inter val display on the
instrument display pr ovides information on the
re maining time or dis tance be fore the next
service due date.
Yo u can hide this service display using the back
button on the left-hand side of thesteering
wheel.
Depending on how theve hicle is used, the
ASS YST PLUS service inter val display may
shor tenth e service inter val, e.g. in thefo llowing
cases:
R mainly short-dis tance driving
R when the engine is of ten le ftidling for long
periods
R intheeve nt of frequent cold start phases
R vehicles with a diesel particulate filter: in
th eev ent of frequently inter rupted rege nera‐
tion of the diesel particulate filter Mercedes-Benz
recommends avoiding such
operating conditions.
Yo u can obtain information concerning the serv‐
icing of your vehicle from a qualified specialist
wo rkshop, e.g. a Mercedes-Benz Service Centre. Displaying
the service due da te On-board computer:
4 Service 5
ASSYST PLUS
The next service due date is displa yed. #
Toexitth e displa y:press the back button
on the left-hand side of thesteering wheel.
Bear in mind thefo llowing related topic:
R Operating the on-board computer
(/ page 243). Infor
mation on regular maintenance work *
NO
TEPremature wearthro ugh failure to
obser veservice due dates Service
workwhich is not car ried out at the
ri ght time or incomple tely can lead to
inc reased wear and damage totheve hicle. #
Alw ays obser vethe prescribed service
inter vals. #
Alw ays ha vethe prescribed service
wo rkcar ried out at a qualified specialist
wo rkshop. Special service
requ irements The prescribed service inter
val is based on nor‐
mal operation of theve hicle. Maintenance work
will need tobe per form ed more of ten if theve hi‐
cle is operated under arduous conditions or
increased loads.
The ASS YST PLUS service inter val display is only
an aid. The driver of theve hicle bears responsi‐
bility as rega rdsto whe ther maintenance work
needs tobe per form ed more of tenth an speci‐ 288
Maintenance and care

fi
ed based on the actual operating conditions
and/or loads.
Examples of arduous operating conditions:
R regular city driving with frequent intermedi‐
ate stops
R mainly short-dis tance driving
R frequent operation in mountainous terrain or
on poor road sur faces
R when the engine is of ten le ftidling for long
periods
R operation in particula rly dusty conditions
and/or if air-recirculation mode is frequently
used
In these or similar operating conditions, ha vethe
interior air filter, engine air cleaner, engine oil
and oil filter etc. changed more frequent ly. The
ty re s must be checked more frequently if the
ve hicle is operated under increased loads. Fur‐
th er information can be obtained at a qualified
specialist workshop. Battery disconnection periods
The ASS
YST PLUS se rvice inter val display
can only calculate the service due da tewhen
th e bat tery is connected. #
Notedown the service due date displa yed on
th e instrument display before disconnecting
th e battery (/ page 288). Engine compartment
Ac
tive bonn et(pedestrian pr otection) Operation of
the active bonnet (pedestrian
pr otection)
In cer tain accident situations, the actuation of
th e active bonn etreduces therisk of injury to
pedestrians. The rear area of the bonn etis
ra ised byappr oximately 85 mm.
Fo rth e drive tothewo rkshop, reset the actuated
active bonn etyourself (/ page 289).
Af terth e active bonn ethas been actuated,
pedestrian pr otection may be limited.
Ha ve the full functionality of the active bonn et
re stored in a qualified specialist workshop. Re
setting the active bonnet &
WARNING Risk of bu rns from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler and parts of theex haust sy stem. #
Allow the engine tocool down and only
to uch co mponent parts described in
th efo llowing. Maintenance and care
289

#
With your hand flat, push down active bonnet
1 inthe area around the hinges on bo th
sides (ar rows).
The engine bonnet must engage in position. #
Ifth e active bonn etcan be raised slight lyat
th ere ar in the area of the hinges, repeat the
st ep until it engages cor rectl y. Opening and closing
the bonnet &
WARNING Risk of accident due todriv‐
ing with the bonn etunlo cked
The bonn etmay open and block your vie w. #
Neverre lease the bonn etwhen driving. #
Before every trip, ensure that the
engine bonn etis loc ked. &
WARNING Risk of accident and inju ry
when opening and closing the bonn et
The bonnet may suddenly drop into the end
position. There is a
risk of injury for an yone in the bon‐
net's range of mo vement. #
Open or close the bonn etonly when
th ere is nobody in the bonn et's range of
mo vement. &
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 inju rydue tomoving
parts
Components in the engine compartment may
continue running or start up sudden ly,even if
th e ignition is switched off.
Make sure of thefo llowing before per form ing
ta sks in the engine compartmen t: #
Switch the ignition off. #
Neverre ach into the danger zone sur‐
ro unding moving co mponents, e.g. the
ro tation area of thefa n. #
Remo vejewe llery and watches. #
Keep items of clo thing and hair away
from moving parts. &
WARNING Risk of inju ryfrom touching
co mp onents under voltage
The ignition sy stem and the fuel injection
sy stem workunder high voltage. You could
re cei vean electric shoc k.290
Maintenance and care

#
Neverto uch co mponents of the ignition
sy stem or the fuel injection sy stem
when the ignition is switched on. &
WARNING Risk of bu rns from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler 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 inju ryfrom using the
windscreen wipers while the engine bon‐
net is open
When the engine bonn etis open, and the
windscreen wipers are set in motion, you can
be trapped bythe wiper linkage. #
Alw ays switch off the windscreen wip‐
ers and ignition before opening the
engine bonn et. Opening
the bonnet #
Torelease the bonn et, pull on handle 1. #
Push handle 1ofthe bonn etcatch up wards
and lift the bonn etby appr oximately 40 cm.
Closing the bonnet #
Lowe rth e bonn etto a height of around
20 cm and then allow it tofall, applying a lit‐
tle forc e as you let it go. Main
tenance and care 291

#
Ifth e bonn etcan still be lif ted slightl y,open
th e bonn etagain and close it with a little
more forc e until it engages cor rectly. Engine oil
Che
cking the engine oil le vel using the on-
board compu ter
Re quirements:
R the engine has been warmed up.
R theve hicle is par ked on a le vel sur face.
R The engine is running at idle speed.
The engine oil le vel is de term ined during driving.
De term ining the engine oil le vel can take up to
30 minutes with a normal driving style and even
longer with an active driving style.
On-board computer: 4 Service 5
Engine oil level
Yo u will see one of thefo llowing messages on
th e multifunction display:
R Engine oil level Measuring now : measure‐
ment of the oil le vel is not yet possible. #
Repeat there qu est af ter a maximum of
30 minutes' driving.
R Engine oil level OK andthe bar display for
indicating the oil le vel on the multifunction
display is green and is between "min" and
"max": the oil le vel is cor rect.
R Engine oil level Add 1,0 l andthe bar display
fo r indicating the oil le vel on the multifunc‐
tion display is orange and is below "min": #
Add 1 l of engine oil.
R Reduce engine oil level andthe bar display
fo r indicating the oil le vel on the multifunc‐
tion display is orange and is abo ve"max": #
Drain off any excess engine oil that has been
added. Todo so, consult a qualified specialist
wo rkshop.
R For engine oil level turn on ignition #
Switch on the ignition tocheck the engine oil
le ve l.
R Engine oil level System inoperative : The oil
le ve l sensor is defective or not connec ted. #
Consult a qualified specialist workshop.
R Engine oil level System currently unavail. #
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 component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler 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 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. 292
Maintenance and care

#
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. #
Follow the instructions on the service
inter val display forch anging the engine
oil and obser vethe prescribed change
inter vals. #
Do not use additives. *
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. %
Depending on driving style, theve hicle con‐
sumes up to0.8 lof 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 292). Checking
the coolant le vel &
WARNING Risk of bu rns from hot com‐
ponent parts in the engine compartment
Cer tain component parts in the engine com‐
partment can be very hot, e.g. the engine,
th e cooler 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
If yo u open the cap, you could be scalded. Main
tenance and care 293

#
Let the mo tor cool down before opening
th e 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.
% Further information on coolant
(/ page 353) 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. #
Allow the engine tocool down and only
to uch co mponent parts described in
th efo llowing. &
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. 294
Maintenance and care

R
obser vethe information on the cor rect dis‐
ta nce in the equipment manufacturer's oper‐
ating instructions.
R do not direct the nozzle of the high-pressure
cleaner directly at sensitive parts, e.g. tyres,
soft top, wind deflector net, gaps, elect rical
components, batteries, light sou rces and
ve ntilation slits. Wa
shing the vehicle byhand *
NO
TEEngine dama gedue towater
ingress #
Take care not topoint thewate r jet
directly towa rdsth e air inlet grille below
th e bonn et. obser
vethe legal requ irements, e.g. in a number
of countries, washing byhand is only permitted
in specially designated wash ba ys. #
Use a mild cleaning agent, e.g. car shampoo. #
Washtheve hicle with luk ewarmwate r using
a soft car sponge. When doing so, do not
ex pose theve hicle todirect sunlight. #
Carefully hose theve hicle off with water and
dry using a chamois.
% Obse rveth e no tes on the care of car parts
(/ page 301). Note
s on paint work/matt finish paint work
care Obse
rveth e no tes on cleaning and care toavo id
damaging the paintwor k.
Pa int
R Insect remains: soak with insect remo ver and
ri nse off the treated areas af terw ards.
R Bird droppings: soak with water and rinse off
af te rw ards.
R Tree resin, oils, fuels and greases: remo veby
ru bbing gently wi tha clo thsoaked in petro‐
leum ether or lighter fluid.
R Coolant and brake fluid: remo vewith a damp
clo thand clean water. R
Tarst ains: use tar remo ver.
R Wax: use silicone remo ver.
R Do not attach sticke rs,fi lms or similar mate‐
ri als.
R Remo vedirt immediately, where possible.
Matt finish
R Only use care products appr ovedfor
Mercedes-Benz.
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 programmes with a final
hot wax treatment.
R Do not use paint cleane rs, buf fing or polish‐
ing products, gloss preser vers, e.g. wax.
R Alw ays ha vepaintwork repairs car ried out at
a qu alified specialist workshop. Note
s on cleaning decorative foils Obser
vethe no tes on matt finish care in the
ch ap ter "No tes on paintwork/matt finish paint‐ Maintenance and care
297

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 charging
th e12 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 restriction of the maximum charging
vo ltage, the battery or the on-board electron‐
ics can be damaged. #
Only use battery charge rs with a maxi‐
mum charging voltage of 14.8 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.
* NO
TEDama getothe battery from over‐
vo ltage When
charging using a bat tery charge r with‐
out a restriction of the maximum charging
vo ltage, the battery or the on-board electron‐
ics can 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
There is a danger of hydrogen gas igniting
when charging the battery if there is a short
circuit or spar ksstart toform. #
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. #
The described order of the battery
clamps must be obser ved when con‐
necting and disconnecting the batter y. #
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. 314
Breakdown assis tance

&
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 there is suf ficient ventila‐
tion. #
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 can be released. #
Alw ays allow a battery tothaw before
ch arging it or per form ing starting assis‐
ta nce. 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.
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. Breakdown assis
tance 315