engine MERCEDES-BENZ E-CLASS CABRIOLET 2018 Workshop Manual

Non-operational times with the batte rydis‐
connected
The AS SYST PLUS service inter val display
can only calculate the service due da tewhen
th e batte ryis connected.
00BBNotedown the service due date displa yed on
th e instrument display before disconnecting
th e battery (
→page 314).
Engin ecom partment
Active hood (pedestrian pr otection)
Operation of the active hood (pedestrian pro‐
te ction)
In cer tain accident situations, therisk of injury
to pedestrians can be reduced bythe actuation
of the active hood. The rear area of the engine
hood is raised byappr oximately 85 mm.
Fo rth e drive tothewo rkshop, reset the trig‐
ge red active hood yourself. Ifth e active hood
has been triggered, pedestrian pr otection may
be limited. A
qu alified specialist workshop must re-ins tate
th e full functionality of the active hood.
The active hood is not available in all countries.
Re setting the active hood
0071
WARNING Risk of burn s 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.
00BBLet the engine cool down and only
to uch the component parts described
as follo ws .
00BBWith your hand flat, push down active hood
1 inthe area around the hinges on bo th
sides (ar rows).
The engine hood must engage in position.
00BBIf th e active hood can be raised slightly at
th ere ar in the area of the hinges, repeat the
st ep until it engages cor rectl y.
Opening/closing the hood
0071
WARNING Risk of accident if the engine
hood is unlatched while driving
An unloc ked engine hood may open up when
th eve hicle is in motion and block your vie w.
00BBNever unlatch the engine hood while
driving.
00BBBefore every trip, ensure that the
engine hood is latched.
Maintenance and care 31
5

0071WARNING Risk of accident and injury
when opening and closing the engine
hood
When opening or closing the engine hood, it
may suddenly drop into the end position.
There is a risk of injury for an yone in the
engine hood's range of mo vement.
00BBOnly open or close the engine hood
when there are no persons in the
engine hood's range of mo vement.
0071
WARNING Danger of burn s when open‐
ing the hood
If yo u open the hood when the engine has
ove rheated or during a fire inthe engine
compartment, you could come into contact
wit h hot gases or other escaping operating
fl uids.
00BBBefore opening the hood, allow the
engine tocool down.
00BBIntheeve nt of a fire inthe engine com‐
partment, keep the hood closed and
call thefire service.
0071
WARNING Risk of injury duetomoving
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.
Make sure of thefo llowing before per form ing
ta sks in the engine compartmen t:
00BBSwitchthe ignition off.
00BBNe verto uch the danger zone sur round‐
ing moving co mponent parts, e.g. the
ro tation area of thefa n.
00BBRe mo vejewe lry and watches.
00BBKeep items of clo thing and hair away
from moving parts.
0071 WARNING Risk of injury fromtouching
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 receive an electric shoc k.
00BBNeverto uch co mponent parts of the
ignition sy stem or the fuel injection sys‐
te m when the ignition is switched on.
0071
WARNING Risk of burn s 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.
00BBLet the engine cool down and only
to uch the component parts described
as follo ws .
316
Maintenance and care

0071WARNING Risk of injury from usingthe
windshield wipers while the engine hood
is open
When the engine hood is open and the wind‐
shield wipers are set in motion, you can be
trapped bythe wiper linkage.
00BBAlw ays switch off the windshield wipers
and ignition before opening the engine
hood.
00BBTo open: pull lever1 torelease the engine
hood.00BBPush hood catch 1upwards and lift the
hood byappr oximately 15in (40 cm).
00BBToclose: lowe rth e hood and let it fall from a
height of appr oximately 8 in (20 cm).
00BBIfth e hood can still be lif ted slightl y,open
th e hood again and close it with a little more
fo rc e until it engages cor rectl y.
Maintenance and care 317

Engine oil
Checkingthe engine oil le vel using the oil
dip stick
0071
WARNING Risk of burn s 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.
00BBLet the engine cool down and only
to uch the component parts described
as follo ws .
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:
REngine at normal operating temp erature: five
minutes.
00BBPa rk theve hicle on a le vel sur face.
00BBPull oil dipstick 1out and wipe off.
00BBSlowly slide oil dipstick 1into the guide
tube tothestop, and pull it out again af ter
appr oximately thre e seconds.
ROil le vel is cor rect: oil le vel is between 2
and 3.
ROil le velto o low: oil le vel is at 3or
belo w.
ROil le velto o high: oil le vel is abo ve2.
00BBIfth e oil le vel is too lo w,top up with
1. 1 US qt (1 l) of engine oil.
00BBIf th e engine oil le vel is too high, ha vethe
exc ess engine oil remo ved immediately at a
qu alified specialist workshop.
Ad ding engine oil
0071
WARNING Risk of burn s 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.
00BBLet the engine cool down and only
to uch the component parts described
as follo ws .
0071
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.
31 8
Maintenance and care

00BBMake surethat no engine oil is spilled
next tothefiller opening.
00BBAllow the engine tocool off and thor‐
oughly clean the engine oil from compo‐
nent parts before starting theve hicle.
0075 NO
TEEngine damage causedbyan
incor rect oil filter, incor rect oil or addi‐
tives
00BBDo not use engine oils or oil filters
which do not cor respond tothe specifi‐
cations explicitly prescribed forth e
service inter vals.
00BBDo not alter the engine oil or oil filter in
order toachie velonger change inter vals
th an prescri bed.
00BBDo not use additives.
00BBFollow the instructions in the service
inter val display rega rding the oil
ch ange.
0075 NO
TEDama gecaused bytopping up too
much engine oil
Ad ding too much engine oil can cause dam‐
age tothe engine or the catalytic con verter.
00BBHa ve excess engine oil remo ved at a
qu alified specialist workshop.
00BBTu rn cap 1counter-clockwise and remo ve
it.
00BBAd d engine oil.
00BBReplace cap 1and turn it clockwise as far
as it will go.
00BBCheck the oil le vel again (→page 318).
Checking coolant le vel
0071
WARNING Risk of burn s 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.
00BBLet the engine cool down and only
to uch the component parts described
as follo ws .
0071
WARNING Danger of burn s from hot
coolant
The engine cooling sy stem is pressurized,
particularly when the engine is warm. If you
Maintenance and care 31
9

openthe cap, you could bescalded byhot
coolant spr aying out.
00BBLet the mo tor cool down before opening
th e cap.
00BBWhen opening the cap, wearglove s and
pr otective eyew ear.
00BBSlowly turn the cap half a turn toallow
pressure toescape.
00BBPark theve hicle on a le vel sur face.
00BBCheck the coolant temp erature display in the
instrument clus ter.
The coolant temp erature must be below
15 8 °F (70 °C).
00BBSlowly turn cap 1counter-clockwise to
re lie ve ove rpressure.
00BBContinue turning cap 1counter-clockwise
and remo veit.
The coolant le vel is cor rect:
Rifth e engine is cold, up tomar ker bar 2.
Rifth e engine is warm, up to0.6 in (1.5 cm)
ov er mar ker bar 2.
00BBIf necessar y,top up with coolant that has
been appr ovedby Mercedes-Benz.
RFurther information on coolant (→page 391)
Ad ding washer fluid tothe windshield
wa sher sy stem
0071
WARNING Risk of burn s 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.
00BBLet the engine cool down and only
to uch the component parts described
as follo ws .
0071
WARNING Danger of burn s when open‐
ing the hood
If yo u open the hood when the engine has
ove rheated or during a fire inthe engine
compartment, you could come into contact
wit h hot gases or other escaping operating
fl uids.
00BBBefore opening the hood, allow the
engine tocool down.
320
Maintenance and care

00BBIntheeve nt of a fire inthe engine com‐
partment, keep the hood closed and
call thefire service.
0071
WARNING ‑ Risk of fire and injury from
windshield washer concentrate
Wi ndshield 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.
00BBMake sure that no windshield washer
concentrate spills out next tothefiller
opening.
00BBRe mo vecap 1bytheta b.
00BBAd dwa sher fluid.
Cleaning and care
Informa tiononwashing theve hicle in a car
wa sh
0071
WARNING Risk of accident due to
re duced braking ef fect af terwa shing the
ve hicle
The braking ef fect is reduced af terwa shing
th eve hicle.
00BBAfterth eve hicle has been washed,
brake carefully while paying attention to
th e traf fic conditions until the braking
ef fect has been ful lyrestored.
To avo id damage to yourvehicle when using a
car wash, ensure thefo llowing beforehand:
RTo avo id possible water ingress in theve hi‐
cle, it is preferable touse car washes which
allow the high-pressure pre-wash tobe deac‐
tivated (specification forth e con vertible pro‐
gram).
RIt is imperative toavo id a subsequent hot-
wa x treatment.
Maintenance and care 321

apron and aface mas k.Immediate ly
ri nse electrolyte or acid splashes off
with clean water.Consult a docto r if
necessar y.
Wear saf etygl asses.
Ke ep children away.
Obser vethis Opera tor's Manual.
If yo udo not intend touse theve hicle over an
ex tended pe riod of time:
RAc tivate standby mode, or
RConnect the battery toa batte rycharge r
appr ovedby Mercedes-Benz, or
RConsult a qualified specialist workshop to
disconnect the battery
St arting assist ance andcharging the12 V
battery
Ve hicles with a lithium-ion battery
00BBWhen charging the battery and during start‐
ing assis tance, al ways use the jump-s tart
connection point in the engine compartment.
0075 NO
TEDama getothe battery from over‐
vo ltage
When charging using a batte rycharge r with‐
out a maximum charging voltage, the battery
or the on-board electronics may be damaged.
00BBOnly use battery charge rs with a maxi‐
mum charging voltage of 14.4 V.
All other vehicles
00BBWhen charging the battery and during start‐
ing assis tance, al ways use the jump-s tart
connection point in the engine compartment. 0075
NO
TEDamaging the battery thro ugh
ove rvoltage
When charging using a batte rycharge r with‐
out a maximum charging voltage, the battery
or theve hicle electronics may be damaged.
00BBOnly use battery charge rs with a maxi‐
mum charging voltage of 14.8 V.
0071
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.
00BBMake sure that the positive term inal of
th e connected battery does not come
into conta ct withvehicle parts.
00BBNe ver place me tal objects or tools on a
batter y.
00BBWhen connecting and disconnecting the
batter y,yo u must observ eth e descri‐
bed order forth e battery clamps.
34 0
Breakdown assis tance

00BBWhen givingstarting assis tance, al ways
make sure that you only connect bat‐
te ry term inals with identical polarity.
00BBDuring starting assis tance, you must
observ eth e described order for con‐
necting and disconnecting the jumper
cables.
00BBDo not connect or disconnect the bat‐
te ry cla mp s while the engine is running.
0071
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.
00BBAv oid fire , open flames, creating spar ks
and smoking.
00BBMake sure that there is suf ficient venti‐
lation du ring thech arging process and
during starting assis tance.
00BBDo not lean over a batter y.
Ifth 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.
0071 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, batte rygas may be released.
00BBAlw aysth aw a frozen batte ryout firs t
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
0075 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.
00BBAv oid numerous and extended attem pts
to start the engine.
Obser vethefo llowing points during starting
assis tance and when charging the battery:
ROnly use undamaged jumper/charging
cables with a suf ficient cross-section and
insula tedte rm inal clamps.
RNon- insulated parts of thete rm inal clamps
must not come into con tact wi thother me tal
parts while the jumper/charging cable is
connected tothe battery/jump-s tart connec‐
tion point.
RThe jumper/charging cable must not come
into contact wi thany parts which may mo ve
when the engine is running.
Breakdown assist ance34
1

RAlways make sure that nei ther you nor the
battery is elect rostatically charge d.
RKe ep away from fire and open flames.
RDo not lean overth e batter y.
RWhencharging: 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:
RSt arting assis tance may only be pr ovided
using batteries with a nominal voltage of
12 V.
RThe vehicles must not touch.
RGa soline engine: onlyaccept starting assis‐
ta nce if the engine and exhaust sy stem are
cold.
00BBSecure theve hicle byapplying the electric
parking brake.
00BBAu tomatic transmission: shiftthe transmis‐
sion toposition 005D.
00BBMake sure that the ignition and all electrical
consumers are switched off.
00BBOpen the hood.
00BBSlide co ver1 of positive clamp 2onthe
jump-s tarting connection point in the direc‐
tion of the ar row.
00BBConnect positive clamp 2onyour vehicle to
positive pole of the donor battery using the
jumper/charging cable. Alw ays begin with
positive clamp 2onyour ow nve hicle firs t.
00BBDu ring thest arting assist ance proce‐
dure: start the engine of the donor vehicle
and run at idle speed.
00BBConnect the negative pole of the donor bat‐
te ry and ground po int3 ofyour ow nve hicle
by using the jumper/charging cable. Begin
with the donor battery firs t.
00BBDu ring starting assist ance:start the
engine of your ow nve hicle.
00BBDuring thech arging process: start the
ch arging process.
00BBDuring starting assist ance:letthe engines
ru nfo r se veral minutes.
00BBDuring starting assist ance:before discon‐
necting the jumper cable, switch on an elec‐
trical consumer in your ow nve hicle, e.g. the
re ar wind owheater or lighting.
When thest arting assis tance/charging process
is compl ete:
34 2
Breakdown assis tance