2017 MERCEDES-BENZ SLC-Class check engine

Engine
Warning/
indicator
lampNSignaltype
Possible causes/consequences and M
Solutions
;NThe yellow CheckE nginew arning lamp lightsupw hile theengine is running.
Therem ay beamalfunction, for example:
Rin th eengine management
Rin th efuel injection system
Rin th eexhaust system
Rin th eignition system
Rin th efuel system
The emission limit values may be exceeded and th eengine may be in emergency
mode.
XVisitaq ualified specialist workshop immediately.
In somes tates, you must immediately visi taqualified specialist workshop as soon
as th eyellow CheckE nginew arning lamp lightsu p. This is due to thelegal require-
ments in effect in these states. If in doubt,c heck whether suchl egal regulations
apply in th estate in whichy ou are currently driving.
8NThe yellow reservef uel warning lamp lightsupw hile theengine is running.
The fuel leve lhas dropped int othe reserver ange.
XRefuel at th enearest gas station.
8NThe yellow reservef uel warning lamp flashes while th evehicle is in motion.
In addition,t he; CheckE nginew arning lamp may light up.
The fuel fille rcap is no tclosed correctly or th efuel system is leaking.
XCheckt hatthe fuel fille rcap is correctly closed.
XIf th efuelfiller cap is not correctly closed: close thefuel fille rcap.
XIf th efuelfiller cap is closed: visitaq ualified specialist workshop.
?NThe red coolant warning lamp lightsupw hile theengine is runnin gand the
coolant temperatur egauge is at th estart of th escale.
The temperatur esensor for th ecoolant temperatur egauge is faulty.
The coolant temperatur eisnolonger beingm onitored. Thereisar isk of engine
damag eifthecoolant temperatur eistoohigh.
XPull ove rand stop th evehicle safely and switch off th eengine ,payinga ttention
to road and traffic conditions. Do no tcontinue driving unde rany circumstances.
XSecure th evehicle against rolling away (Ypage 131).
XConsult aqualified specialist workshop.
Warning and indicator lamps207
On-boardc omputer and displays
Z

Warning/
indicator
lampNSignal type
Possiblec auses/consequences and M
Solutions
?NThe red coolant warning lamp comes on while the engine is running.
The coolant leve listoo low.
If the coolant leve liscorrect, the airflow to the engine radiator may be blocked or
the electric engine radiator fan may be faulty.
The coolant is too hot and the engine is no longer being cooleds ufficiently.
XObserve the additionaldisplay messages in the multifunction display.
XPul lover and stop the vehicles afelyand switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehiclea gainst rolling away(Ypage131).
XLeave the vehiclea nd keepasafe distance from the vehicleu ntil the engine has
cooledd own.
XCheck the coolant leve land add coolant, observing the warning notes
(Ypag e233).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked ,e.g. by snow,
slush or ice.
XDo not start the engine again until the coolant temperature gauge is below the H
marking (Ypag e164). Otherwise, the engine coul dbedamaged.
XDrive to the neares tqualified specialist workshop.
XAvoid heavy loads on the engine as you do so, e.g. driving in mountainous terrain
and stop-and-go traffic.
?N The red coolant warning lamp comes on while the engine is running.
The coolant temperature gauge has exceededt heHmarking (
Ypag e164) .The
airflow to the engine radiator may be blocked or the coolant leve lmay be too low.
GWARNING
The engine is not being cooleds ufficiently and may be damaged.
Do not drive when you rengine is overheated. This can caus esome fluids which
may have leaked into the engine compartment to catch fire.
Steam from the overheated engine can als ocaus eserious burns which can occur
just by opening the hood.
There is arisk of injury.
XObserve the additiona ldisplay messages in the multifunction display.
XPul lover and stop the vehicles afelyand switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehiclea gainst rolling away(Ypage131).
XLeave the vehiclea nd keepasafe distance from the vehicleu ntil the engine has
cooledd own.
XCheck the coolant leve land add coolant, observing the warning notes
(Ypag e233).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked ,e.g. by snow,
slush or ice.
208Warning and indicator lamps
On-board computer and displays

XReachintot he gap, pull hoo dcatch handle ;
up and lift hoo d:.
If you lift th ehoodbya pproximately 15 in
(40 cm), th ehoodiso pened and held open
automatically by th egas-filled strut .
Closingthehood
XLowe rthe hoo dand let it fall from aheight of
approximately 8in(20 cm).
XChec kthatthe hoo dhas engage dproperly.
If th ehoodc an be raised slightly, it is no t
properly engaged. Open it again and close it
wit hal ittlem oref orce .
Engine oil
Notes on th eoil level
Dependin gonyour driving style, th evehicl e
consumes up to 0. 9USqt(0.8 liters )ofoilpe r
60 0m iles (1,000 km). Th eoilcons umption may
be higher than th iswhen th evehicle is newori f
you frequently driveath igh engines peeds.
Dependin gontheengine, th eoil dipst ick may be
in ad ifferent location.
When checking th eoilleve l:
Rpark th evehicle onaleve lsurface
Rthee ngines hould be swit ched off for approx-
imately fiv eminute sift heengineisatn ormal
operatin gtem perature
Rifth ee ngineisn otat normal operatin gtem -
perature, e.g .iftheenginew as onlystarted
brie fly,wait about 30 minute sbefore carrying
out the measurement
Checking the oil level using the oil dip-
stick
GWARNING
Certain component sinthe engine compart-
ment ,such as the engine, radiator and parts
of the exhaust system, can become very hot.
Workin ginthe engine compartment poses a
risk of injury.
Where possible, let the engine cool down and touch only the component sdescribed in the
following.
ExampleXPull oil dipstick :out of the dipstick guide
tube.
XWipe off oil dipstick :.
XSlowly slide oil dipstick :into the guide tube
to the stop, and take it out again.
If the level is between MIN mark =and MAX
mark ;,the oil level is correct.
XIf the oil level has dropped to MIN mark =or
below, add 1.1 US qt (1.0 liter) of engine oil.
Adding engine oil
GWARNING
Certain component sinthe engine compart-
ment ,such as the engine, radiator and parts
of the exhaust system, can become very hot.
Workin ginthe engine compartment poses a
risk of injury.
Where possible, let the engine cool down and touch only the component sdescribed in the
following.
232Engine compartment
Maintenance and care

GWARNING
If engine oil comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is arisk of fire and injury.
Make sure that engine oil is not spilled next to
the filler neck. Let the engine cool downa nd
thoroughly clea nthe engine oil off the com-
ponents before starting the engine.
HEnvironmental note
When adding oil,t ake care not to spil lany. If
oil enters the soil or waterways, it is harmfu lto
the environment.
!Only use engine oilsa nd oil filters that have
been approved for vehicles with aservice sys-
tem. You can obtai nalist of the engine oils
and oil filters tested and approved in accord- ance with the Mercedes-Benz Specifications
for Service Products at any Mercedes-Benz
Service center.
Damag etothe engine or exhaust system is
caused by the following:
Rusing engine oilsa nd oil filters that have not
been specifically approved for the service
system
Rreplacing engine oil and oil filters after the
interval for replacement specified by the
service system has been exceeded
Rusing engine oil additives.
!Do not add too much oil.Ift he oil levelis
above the "max" mark on the dipstick, too
much oil has been added. This can lea dto
damage to the engine or the catalytic con-
verter. Have excess oil siphoned off.
Example :engine oil cap
XTurn cap :counter-clockwise and remove it.
XAdd engine oil.
If the oil leve lisatorbelow the MIN mark on
the oil dipstick, add 1.1 US qt (1.0 liter) of
engine oil.
XReplace cap :on the filler neck and turn
clockwise.
Ensure that the cap locks into place securely.
XCheck the oil leve lagain with the oil dipstick
(Ypag e232).
Further information on engine oil (
Ypag e286).
Checkin gand adding other service
products
Checkin gcoolantl evel
GWARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible,l et the engine cool downa nd
touch only the components described in the
following.
GWARNING
The cooling system is pressurized, particularly
when the motor is warm .Ifyou open the cap,
you coul dbescalded if hot coolant sprays out.
There is arisk of injury.
Let the engine cool downb efore you open the
cap. Wearg lovesand eye protection. Slowly
open the cap to relieve pressure.
Example
Engine compartment233
Maintenance and care
Z

XPark the vehicle onalevel surface.
Only check the coolant level when the vehicle is on alevel surface and the engine has cooled
down.
XTurn the SmartKey to position 2in the ignition
lock (Ypage 115).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (
Ypage 115).
XCheck the coolant temperature gauge in the
multifunction display.
The coolant temperature must be below
158 ‡(70 †).
XTurn the SmartKey to position 0(Ypage 115)
in the ignition lock.
XSlowly turn cap ;half aturn counter-clock-
wise to allow excess pressure to escape.
XTurn cap ;further counter-clockwise and
remove it.
If the coolant is at the level of marker bar =
in the filler neck when cold, there is enough
coolant in coolant expansion tank :.
If the coolant level is approximately 0.6 in
(1.5 cm) above marker bar =in the fuel filler
neck when warm, there is enough coolant in
expansion tank :.
XIf necessary, add coolant that has been tested
and approved by Mercedes-Benz.
XReplace cap;and turn it clockwise as far as
it will go.
For further information on coolant ,see
(
Ypage 287).
Windshield washer system
GWARNING
Certain components in the engine compart-
ment ,such as the engine, radiator and parts
of the exhaust system, can become very hot.
Workin ginthe engine compartment poses a
risk of injury.
Where possible, let the engine cool down and touch only the components described in the
following.
GWARNING
Windshield washer concentrate could ignite if it comes into contact with hot engine compo-
nentsort he exhaust system. There is arisk of
fire and injury.
Make sure that no windshield washer con-
centrate is spilled next to the filler neck.
Example
XTo open: pull cap:upwards by the tab.
XAdd the premixed washer fluid.
XTo close: press cap :ontothe filler neck
until it engages.
If the washer fluid level drops below the recom-
mended minimum fluid level of 1USgal (1 liter),
am essage appears in the multifunction display
promptin gyou to add washer fluid (
Ypage 201).
Further information on windshield washer fluid/
antifreeze (
Ypage 288).
Overview of the engine compartment
Example: gasoline engine
:
Engine oil cap
;Oil dipstick
=Brake fluid reservoir
?Washer fluid reservoir
ACoolant expansion tank
234Overview of the engine compartment
Maintenance and care

ASSYSTPLUS
Service messages
The ASSYS TPLUSs ervic einterval display
inform syou of th enexts ervic edue date.
Information on th etypeofs erviceand servic e
intervals (see th eseparat eMaintenance Book -
let).
You can obtain further information from an
authorize dMercedes-Benz Cente rorat
http://www.mbusa.co m(USAo nly).
iThe ASSYS TPLUSs ervic einterval display
does no tsho wa ny information on th eengine
oil level. Observ ethe note sont heengin eoil
level (
Ypage 232).
The multifunction display shows aservic emes-
sage for several seconds, e.g. :
RServiceAin..D ays
RServic eADue
RServic eAExceeded by .. Day s
Dependingontheoperating condition softhe
vehicle, th eremaining time or distanc euntil th e
next servic edue dat eisdisplayed.
The lette rA
or B,possibl yinconnectio nwitha
number or another letter, shows th etypeofs er-
vice. A
stand sfor am inor servic eand Bfor a
major service.
You can obtain further information from an
authorize dMercedes-Benz Center.
The ASSYS TPLUSs ervic einterval display does
no ttak eintoa ccoun tany periods of time during
whic hthe battery is disconnected.
Maintainin gthe time-dependen tservic esched-
ule:
XNot edown th eservic edue dat edisplayed in
th em ultifunction display before disconnect -
ing th ebattery.
or
XAfte rreconnecting th ebattery, subtrac tthe
battery disconnection periods from th eser-
vic ed ates hown on th edisplay.
Hiding aservice message
XPress th ea or% buttononthesteering
wheel.
Displaying service messages
XSwitc hont heignition .
XPress th e= or; buttononthesteering
whee ltos elect th eServ.menu.
XPress th e9 or: buttontos elect th e
ASSYSTPLU Ssubmen uand confirm by press-
ing th ea button.
The servic edue dat eappear sinthemulti-
function display.
Infor mation abou tService
Resetting th eASSYSTP LUS service
interval display
!If th eASSYSTP LUSs ervic einterval display
has been inadvertentl yreset ,thiss etting can
be correcte dataqualified specialist work-
shop.
Hav eservic eworkc arrie dout as described in
th eM aintenance Booklet .This may otherwise
lead to increased wear and damag etothe
major assemblies or th evehicle.
Aq ualified specialist workshop ,e.g.ana uthor-
ized Mercedes-Benz Center, will reset th e
ASSYS TPLUSs ervic einterval display after th e
servic eworkh as been carrie dout.Y ou can also
obtain further information on maintenance
work, for example.
Special service requirements
The specifie dmaintenance interval takes only
th en orma loperation of th evehicl einto
account. Under arduous operating condition sor
increased load on th evehicle, maintenance
wor km ustbec arriedout mor efrequently, for
example:
Rregular cit ydrivin gwithf requen tintermediat e
stops
Rif th evehicl eisp rimarily used to travel short
distances
Ruse in mountainous terrain or on poor road
surfaces
Rif th eengineiso ften lef tidlin gfor lon gperiods
Under these or similar conditions, have, for
example, th eair filter, engin eoil and oil filter
replace dorchanged mor efrequently. Under
arduous operating conditions, th etires mus tbe
checke dmoreo ften .Further information can be
ASSYST PLUS235
Maintenance and care
Z

XIf possible, bring the front wheelsinto the
straight-ahea dposition.
XSwitch off the engine.
XVehicles without KEYLESS-GO: remove the
SmartKey from the ignition lock.
XVehicles with KEYLESS-GO: open the driv-
er's door.
The on-board electronics now have status 0.
This is the same as the SmartKey having been
removed.
XVehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock
(
Ypage 115).
XMake sure that the passengers are not endan-
gered as they do so. Make sure that no one is near the danger area whileaw heel is being
changed. Anyone who is not directly assisting
in the wheel change should, for example,
stand behind the barrier.
XGet out of the vehicle.P ay attention to traffic
conditions when doing so.
XClos ethe driver's door.
MOExtended tires (tires with run-flat
properties)
General notes
With MOExtended tires (tires with run flat char-
acteristics), you can continue to drive you rvehi-
cle even if there is atotal loss of pressure in one
or more tires. The affected tire must not show
any clearl yvisible damage.
You can recognize MOExtended tires by the
MOExtended marking which appears on the
sidewall of the tire. You wil lfind this marking
next to the tire size designation, the load-bear-
ing capacity and the speed index (
Ypage 269).
MOExtended tires may only be used in conjunc-
tion with an active tire pressure loss warning
system or with an active tire pressure monitor.
If ap ressure loss warning message appears
in the multifunction display:
Robserve the instructions in the display mes-
sages (Ypage 196).
Rcheck the tire for damage.
Rif driving on, observe the following notes.
The driving distance possible in run-flat mode is
approximately 50 miles (80 km) when the vehi-
cle is partially laden and approximately 19 miles
(30 km) when the vehicle is full yladen. In addition to the vehicle load
,the driving dis-
tance possible depends upon:
Rvehicle speed
Rroad condition
Routsid etemperature
The driving distance possible in run-flat mode
may be reduced by extreme driving conditions
or maneuvers, or it can be increased through a
moderate style of driving.
The driving distance possible in run-flat mode is
counted from the moment the tire pressure loss
warning appears in the multifunction display.
You must not exceed amaximum speed of
50 mph (80 km/h).
When replacing one or all tires, please observe
the following specifications for you rvehicle's
tires:
Rsize
Rtype and
Rthe "MOExtended" mark
If at ire has gone flat and cannot be replaced
with aMOExtended tire, astandard tire may be
used as atemporary measure. Make sure that
you use the proper size and type (summe ror
winter tire).
Vehiclese quipped with MOExtended tires are
not equipped with aTIREFIT kit at the factory. It
is therefore recommended that you additionally
equi pyourvehicle with aTIREFIT kit if y
ou mount
tires that do not feature run-flat properties, e.g.
winter tires. ATIREFIT kit is available, for exam-
ple, from aqualifieds pecialist workshop.
Important safety notes
GWARNING
When driving in emergency mode, the driving
characteristics deteriorate, e.g. when corner-
ing, accelerating quickly and when braking.
There is arisk of an accident.
Do not exceed the stated maximum speed.
Avoid abrupt steering and driving maneuvers,
and driving over obstacle s(curbs, potholes,
off-road). This applies in particular to aladen
vehicle.
Stop driving in emergency mode if:
Ryou hear banging noises.
Rthe vehicle starts to shake.
242Flat tire
Breakdowna ssistance

The vehicle will then use very little energy, thus
conserving battery power.
If the power supply has been interrupted, e.g. ifyou reconnect the battery, you will have to:
Rreset the function for automatically folding
the exterior mirrors in/out by folding the mir-
rors out once (
Ypage 89)
Rset the clock (see the Digital Operator's Man-
ual)
On vehicles with amultimedia system, the
time is set automatically.
Charging the battery
GWARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, open flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over abattery.
GWARNING
Battery acid is caustic. There is arisk of injury.
Avoid contact with skin, eyes or clothing. Do
not inhale any battery gases. Do not lean over
the battery. Keep children away from batter-
ies. Wash away battery acid immediately with
plenty of clean water and seek medical atten-
tion.
GWARNING
Ad ischarged battery can freeze at tempera-
tures below freezin gpoint. When jump-start-
ing the vehicle or charging the battery, gases can escape from the battery. There is arisk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
!Only use battery chargers with amaximum
charging voltage of 14.8 V.
!Only charge the battery using the jump-
starting connection point.
The jump-starting connection point is in the
engine compartment. If the indicator/warning lamps do not light up at
low temperatures, it is very likely that the dis-
charged battery has frozen. In this case, you
may neither charge the battery nor jump-start
the vehicle. The service life of
athawed-out bat-
tery may be shorter .The starting characteristics
can be impaired, particularly at low tempera-
tures. Have the thawed-out battery checked at a
qualified specialist workshop.
Read the battery charger's operating instruc-
tions before charging the battery.
XOpen the hood.
XConnectt he battery charger to the positive
terminal and ground point in the same order
as when connectin gthe donor battery in the
jump-starting procedure (
Ypage 249).
248Battery (vehicle)
Breakdown assistance