engine MERCEDES-BENZ E-CLASS CABRIOLET 2017 Repair Manual

Opening/closing
the bonnet &
WARNING Risk of accident due todriv‐
ing with the engine bonn etunlo cked
An unloc ked engine bonn etmay open up
when theve hicle is in motion and block your
vie w. #
Never unlock the engine 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 engine
bonn et
When opening or closing the engine bonn et,
it may suddenly drop into the end position.
There is a risk of injury for an yone in the
engine bonn et's range of mo vement. #
Only open or close the engine bonn et
when there are no persons in the
engine 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
Cer tain components in the engine compart‐
ment may continue tomo veor suddenly
mo veagain even af terth e ignition has been
switched off, e.g. the cooler fan.
Ma kesure of thefo llowing before per form ing
ta sks in the engine compartmen t: #
Switch the ignition off. #
Neverto uch the danger zone sur round‐
ing moving co mponent parts, 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 onent parts under voltage
The ignition sy stem and the fuel injection
sy stem workunder high voltage. If youto uch
co mp onent parts which are under voltage,
yo u could recei vean electric shoc k. #
Neverto uch co mponents of the ignition
sy stem or the fuel injection sy stem
when the ignition is switched on. &
WARNING Danger of bu rns from hot
component parts in the engine compart‐
ment
Cer tain component parts in the engine com‐
partment may be very hot, e.g. the engine, Maintenance and care
347

th
era diator and parts of theex haust sy stem. #
Let the engine cool down and only
to uch the component parts described
below: &
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. #
Toopen: pull lever1 torelease the engine
bonn et. #
Push bonnet catch 1upwards and lift the
bonn etby appr oximately 40 cm. #
Toclose: lowe rth e bonn etand let it fall from
a height of appr oximately 20 cm. #
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. 348
Maintenance and care

Engine oil
Checking
the engine oil le vel using the oil
dip stick &
WARNING Danger of bu rns from hot
component parts in the engine compart‐
ment
Cer tain component parts in the engine com‐
partment may be very hot, e.g. the engine,
th era diator and parts of theex haust sy stem. #
Let the engine cool down and only
to uch the component parts described
below: Depending on
the engine, the oil dipstick may be
ins talled in the engine compartment in dif fere nt
locations.
Wa iting time before checking the oil le vel:
R Engine at normal operating temp erature: five
minutes. R
Engine not at normal operating temp erature
(e.g. the engine was only star ted brief ly): 30
minutes. #
Park theve hicle on a flat sur face. #
Remo veoil dipstick 1and wipe off. #
Slowly slide oil dipstick 1into the guide
tube tothestop, and take it out again af ter
appr oximately thre e seconds.
R Oil le vel is cor rect: oil le vel is between 2
and 3.
R Oil le velto o low: oil le vel is at 3or
belo w.
R Oil le velto o high: oil le vel is abo ve2 . #
Ifth e oil le vel is too lo w,top up with 1 l of
engine oil. #
Ifth e engine oil le vel is too high, ha vethe
exc ess engine oil remo ved immediately at a
qu alified specialist workshop.
Checking the engine oil le vel using the on-
board compu ter (E 220 d)
The engine oil le vel is de term ined during driving.
The oil le vel display is only available af ter a driv‐
ing time of up to30 minutes and if the ignition is
switched on, depending on the driving profile.
It is not possible tocor rectly measu rethe oil
le ve l if:
R The vehicle is not le vel during the measuring
process. Maintenance and care
349

R
The bonnet has been pr eviously opened.
The engine must be restar ted and the engine oil
le ve l will be de term ined again during driving.
On-board computer: , Service .
Engine oil level:
Yo u will see one of thefo llowing display
messa ges in the multifunction displa y:#
Engine oil level Measuring now: measu re‐
ment of the oil le vel is not yet possible.
Re peat there qu est af ter a maximum of 30
minutes' driving. #
Engine oil level OK andthe bar display for
indicating the oil le vel in the multifunction
display is green and is between "min" and
"max": the oil le vel is cor rect. #
Engine oil level Add 1.0 l andthe bar display
fo r indicating the oil le vel in the multifunction
display is orange and is below "min": top up
with 1 l of engine oil. #
Reduce engine oil level andthe bar display
fo r indicating the oil le vel in the multifunction
display is orange and is abo ve"max": drain off
theexc ess engine oil. Consult a qualified
specialist workshop. #
For engine oil level turn on ignition: switch on
th e ignition tocheck the engine oil le vel. #
Engine oil level System inoperative : sensor
fa ulty or not connected. Consult a qualified
specialist workshop. #
Engine oil level System currently unavail. :
close the engine bonn et.
To pping up engine oil &
WARNING Danger of bu rns from hot
component parts in the engine compart‐
ment
Cer tain component parts in the engine com‐
partment may be very hot, e.g. the engine,
th era diator and parts of theex haust sy stem. #
Let the engine cool down and only
to uch the component parts described
below: &
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. #
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. #
Do not alter the engine oil or oil filter in
order toachie velonger change inter vals
th an presc ribed. #
Do not use additives. 350
Maintenance and care

#
Follow the instructions in the service
inter val display rega rding the oil
ch ange. *
NO
TEDama gecaused bytopping up too
much engine oil To
pping up too much engine oil can cause
damage tothe engine or the catalytic con‐
ve rter. #
Have excess engine oil remo ved at a
qu alified specialist workshop. #
Turn cap 1anti-clockwise and remo veit. #
Top up the engine oil. #
Replace cap 1and turn it clockwise as far
as it will go. #
Check the oil le vel again (→ page 349). Checking
the coolant le vel &
WARNING Danger of bu rns from hot
component parts in the engine compart‐
ment
Cer tain component parts in the engine com‐
partment may be very hot, e.g. the engine,
th era diator and parts of theex haust sy stem. #
Let the engine cool down and only
to uch the component parts described
below: &
WARNING Danger of bu rns 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 mo tor cool down before opening
th e cap. #
When opening the cap, wearglove s and
pr otective eyew ear. Maintenance and care
351

#
Slowly turn the cap half a turn toallow
pressure toescape. #
Park theve hicle on a flat 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 torelie ve
ov erpressure. #
Continue turning cap 1anti-clockwise and
re mo veit.
The coolant le vel is cor rect:
R Ifth e engine is cold, up tomar ker bar 2
R Ifth e engine is warm, up to1.5 cm over
mar ker bar 2 #
If necessar y,top up with coolant that has
been appr ovedby Mercedes-Benz.
R Further information on coolant (→ page414) To
pping up the windsc reen washer sy stem &
WARNING Danger of bu rns from hot
component parts in the engine compart‐
ment
Cer tain component parts in the engine com‐
partment may be very hot, e.g. the engine,
th era diator and parts of theex haust sy stem. #
Let the engine cool down and only
to uch the component parts described
below: &
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. 352
Maintenance and care

St
arting assi stance and charging the12 V
battery Ve
hicles with a lithium-ion battery #
When charging the battery and during start‐
ing assis tance, al ways use the jump-s tart
connection 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. *
NO
TEShor tening the service life of the
battery bycharging the battery at low
te mp eratures Charging
the battery at very low temp era‐
tures may shor tenth e service life of the bat‐
te ry and ha vea negative ef fect on starting. #
Do not charge the battery at very low
te mp eratures. All
other vehicles #
When charging the battery and during start‐
ing assis tance, al ways use the jump-s tart
connection point in the engine compartment.
* 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. Breakdown assis
tance 373

#
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. 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. &
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. The service li
feof a battery that has been
th awe d may be dramatically shor tened. 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 leads/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.
R When charging: only use battery charge rs
te sted and appr ovedby Mercedes-Benz and
re ad 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. #
Secure theve hicle byapplying the electric
parking brake. 374
Breakdown assis tance

#
Automatic transmission: Shiftthe trans‐
mission toposition j. #
Make sure that the ignition and all electrical
consumers are switched off. #
Open the engine bonn et. #
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
positive pole of donor battery using the jump
lead/charging cable. Alw ays begin with posi‐
tive clamp 2onyour ow nve hicle firs t. #
During thest arting assi stance proce‐
dure: 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 on your ow nve hicle, e.g. there ar
wind owheater or lighting.
When thest arting assis tance/charging process
is compl ete: #
First,re mo vethe jump lead/charging cable
from ear thpoint 3and negative pole of the
donor batter y,then from positive clamp 2
and positive pole of the donor batter y.Begin
ea ch time wi th the conta cts onyour own
ve hicle firs t. #
Afterre moving the jump lead/charging
cable, close co ver1 of positive clamp 2.
Yo u can obtain fur ther information on starting
assis tance at any qualified specialist workshop. To
w starting or towing away Pe
rm itted towing me thods Mercedes-Benz
recommends transporting your
ve hicle in the case of a breakdown, rath er than
to wing it away.
* NO
TEDama getotheve hicle due to tow‐
ing away incor rectly #
Obser vethe instructions and no tes on
to wing away. Breakdown assis
tance 375

Pe
rm itted towing me thods 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 No Yes, if thesteering wheel is fixe d in
th e cent reposition with a steering
wheel loc k.
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 (→ page375) (→ page376). #
Makesure that the battery is connected and
ch arge d.
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.
% Vehicles with automatic transmission: if
th e automatic transmission cann otbe shif‐
te dto position i, havetheve hicle trans‐
por tedaw ay ( →page 378). A towing vehicle
with lifting equipment is requiredforve hicle
transpor tation. 376
Breakdown assis tance