2018 MERCEDES-BENZ E-CLASS CABRIOLET check engine

ASSYST PLUS serv ice interval display
Fu nction of the ASS YST PLUS serv ice interval
displ ay
The ASS YST PLUS service inter val display in the
instrument display pr ovides information on the
re maining time or dis tance be fore the next
service due date.
Yo u can hidethis service message using the
back button on the left-hand side of thesteering
wheel.
Yo u can obtain fur ther information concerning
th e servicing of your vehicle from a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
Displaying the service due da te
On-board computer:
00866HUYLFH00CF$66<67 3/86
The next service due date is displa yed.
00BBTo exitth e displa y:press the back button
on the left-hand side of thesteering wheel. Make sure
toobser vethefo llowing fur ther rela‐
te d subjec t:
ROperating the on-board computer
(→page 200).
Car rying out maintenance workatregular
inter vals
0075 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.
00BBAlw ays obser vethe prescribed service
inter vals.
00BBAlw 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 tenth an
specified if theve hicle is operated under ardu‐
ous conditions or increased loads, forex ample:
Rregular city driving with frequent intermedi‐
ate stops.
Rif th eve hicle is primarily used for short-dis‐
ta nce driving.
Rfor frequent operation in mountainous terrain
or on poor road sur faces.
Rifth e engine is of ten le ftidling for long peri‐
ods.
Rin particula rly dusty condition sand/o rif air -
re circulation mode is frequently used.
In these or similar operating conditions, ha vethe
interior air filter, engine air cleaner, engine oil, oil
fi lter etc. changed more frequent ly.Th etire s
must be checked more frequently if theve hicle
is operated under increased loads. Further infor‐
mation can be obtained at a qualified specialist
wo rkshop.
31 4
Maintenance and care

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

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

00BBTurn clip 2on co ver1 aqu arter-turn to
th e left.
00BBPull co ver1 upwards in the direction of the
ar row .
00BBRemo veany existing moisture from the fuse
box using a dry clo th.
00BBLoosen scr ews4, remo vefuse box lid 3
from theto p.
Closing
00BBCheck whe ther the seal is positioned cor‐
re ctly in the lid.
00BBInsert the lid into the brac ket at there ar of
th e fuse box.
00BBFo ld down lid of the fuse box and tighten
scr ews4.
00BBInsert co ver1 on bo thsides and engage
th e saf etyclips.
00BBTu rn clip 2on co ver1 one quarter-turn to
th eright.
00BBClose the engine hood.
Dashboard fuse box
The fuse box is on the side of the dashboard
under a co ver.
00BBConta ct an au thorized Mercedes-Benz Cen‐
te rfo r fur ther information.
Fu se box in the front-passenger foot we ll
Obser vethe no tes on electrical fuses
(→page 348).
350 Breakdown assis tance

Displaymessages
Possible causes/consequences and 0050Solutions
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2SHUDWRU
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heradar sensor sy stem is malfunctioning. Possible causes are:
RSoiling of the sensors
RHeavy rain
REx tended country driving wi thout moving traf fic, e.g. in the desert
Driving sy stems and driving saf etysy stems may be malfunctioning or temp orarily una vailable.
Once the cause of the problem is no longer present, driving sy stems and driving saf etysy stems are available again.
If th e display message does not disappear:
00BBPull over and stop theve hicle safely as soon as possible, paying attention toroad and traf fic conditions.
00BBClean all sensors .
00BBRestart the engine.
0075
Example:/HIW 6LGH &XUWDLQ
$LUEDJ 0DOIXQFWLRQ 6HUYLFH
5HTXLUHG *T
he cor responding head air bag is malfunctioning.
0071
WARNING Risk of injury or death duetomalfunctions in the head air bag
If th e head air bag is malfunctioning, it might be triggered unintentionally or might not be triggered at all in the
eve nt of an accident wi tha high rate ofvehicle deceleration.
00BBHa ve the head air bag checked and repaired immediately at a qualified specialist workshop.
00BBConsult a qualified specialist workshop immediatel y.
Displaymessage s andwarning/indicator lamps 407

Displaymessages
Possible causes/consequences and 0050Solutions
00B2
&KHFN (QJLQH 2LO $W 1H[W
5HIXHOLQJ*T
he engine oil le vel has dropped tothe minimum le vel.
0075 NO
TEEngine damage causedbydriving with insuf ficient engine oil00BBAv oid long journe yswith insuf ficient engine oil.
00BBCheck the engine oil le vel when next refueling.
To p up the engine oil (
→page 318).
No tes on engine oil (
→page 389).
00B6
)XHO /HYHO /RZ *T
he fuel supply has dropped into there ser verange.
00BBRe fuel.
00B6
*DV &DS /RRVH *T
here has been pressure loss in the fuel sy stem. The fuel filler cap is not closed cor rectly or the fuel sy stem is
leaking.
00BBClose the fuel filler cap.
00BBIf th e fuel filler cap was already proper lyclosed: consult a qualified specialist workshop.
00AC
*T hefan mo tor is defective.
00BBAv oiding high loads on the engine, drive on tothe nearest qualified specialist workshop. In doing so, ensure that
th e coolant temp erature display remains below there d marking.
424
Display messages and warning/indicator lamps