check engine MERCEDES-BENZ S-Class CABRIOLET 2017 A217 Owner's Guide

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
?NThe red coolant warning lamp comes on while the engine is running.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may be blocked or
the electric engine radiator fan may be defective.
The coolant is too hot and the engine is no longer being cooled sufficiently.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 140).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 276).
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 is below 257 ‡
(125 †). Otherwise, the engine could be damaged.
XDrive to the nearest qualified 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. A warning
tone also sounds.
The coolant temperature has exceeded 255 ‡(124 †). The airflow to the engine
radiator may be blocked or the coolant level may be too low.
GWARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive when your engine is overheated. This can cause some fluids which
may have leaked into the engine compartment to catch fire.
Steam from the overheated engine can also cause serious burns which can occur
just by opening the hood.
There is a risk of injury.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 140).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 276).
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.
Warning and indicator lamps in the instrument cluster239
On-board computer and displays
Z

Vehicle
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
ÐNThe red power steering warning lamp is lit while the engine is running.
The power steering is malfunctioning.
A warning tone also sounds.
GWARNING
You will need to use more force to steer.
There is a risk of an accident.
XCheck whether you are able to apply the extra force required.
If you are able to steer safely:
XDrive on carefully.
XVisit a qualified specialist workshop immediately.
If you are unable to steer safely:
XDo not drive on.
XConsult a qualified specialist workshop.
242Warning and indicator lamps in the instrument cluster
On-board computer and displays

XMake sure that the windshield wipers are
turned off.
XPull release lever:on the hood.
The hood is released.
XReach into the gap, pull hood catch handle ;
up and lift the hood.
If you lift the hood by approximately 15 in
(40 cm), the hood is opened and held open
automatically by the gas-filled strut.
Closing the hood
XLower the hood and let it fall from a height of
approximately 8 in (20 cm).
XCheck that the hood has engaged properly.
If the hood can be raised slightly, it is not
properly engaged. Open it again and close it
with a little more force.
Radiator
Do not cover up the radiator, such as with a
thermal mat or insect protection cover. The
readings of the on-board-diagnostic system may
otherwise be inaccurate. Some of these read-
ings are required by law and must be accurate at
all times.
Engine oil
Important safety notes
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, let the engine cool down and touch only the components described in the
following.
GWARNING
The engine compartment contains moving
components. Certain components, such as
the radiator fan, may continue to run or start
again suddenly when the ignition is off. There is a risk of injury.
If you need to do any work inside the engine
compartment:
Rswitch off the ignition
Rnever reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area
Rremove jewelry and watches
Rkeep items of clothing and hair, for exam-
ple, away from moving parts
GWARNING
If engine oil comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Make sure that engine oil is not spilled next to
the filler neck. Let the engine cool down and
thoroughly clean the engine oil off the com-
ponents before starting the engine.
GWARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Engine compartment273
Maintenance and care
Z

Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department.
General notes
Depending on your driving style, the vehicle
consumes up to 0.9 US qt (0.8 l) of oil per
600 miles (1000 km). The oil consumption may
be higher than this when the vehicle is new or if
you frequently drive at high engine speeds.
Depending on the engine, the oil dipstick may be
in a different location.
When checking the oil level:
Rpark the vehicle on a level surface
Rthe engine should be switched off for approx-
imately five minutes if the engine is at normal
operating temperature
Rif the engine is not at normal operating tem-
perature, e.g. if the engine was only started
briefly, wait about 30 minutes before carrying
out the measurement
Checking the oil level using the oil dip-
stick (except Mercedes-AMG S 65)
Example: checking the oil level using the oil
dipstick
XPull 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 l)of engine oil.
Checking the oil level using the on-
board computer (Mercedes-AMG S 65)
Calling up the oil level check
XTurn the SmartKey to position 2in the ignition
lock (Ypage 124).
or
XOn vehicles with KEYLESS-GO, press the
Start/Stop button twice (Ypage 124).
XUse ò on the steering wheel to call up the
list of menus.
XPress the :or9 button on the steering
wheel to select the Servicemenu.
XConfirm by pressing aon the steering
wheel.
XUse : or9 to select the EngineOilLevelsubmenu.
XPressato confirm the selection.
The Measuring Engine Oil Level Accu‐
rate Only When Vehicle Is Levelmes-
sage appears in the multifunction display.
The measurement takes a few seconds. A mes-
sage appears in the multifunction display. The
messages are described in the following chap-
ter.
Oil level display messages in the multifunction display
Display messagesPossible causes/consequences and MSolutions
Engine Oil Level OKThe oil level is correct.
Check Engine OilLevel (Add 1 Liter)
The oil level is too low.
XAdd 1.1 US qt (1.0 liter) of engine oil.
274Engine compartment
Maintenance and care

Display messagesPossible causes/consequences andMSolutions
Reduce Engine OilLevel
The engineoil level is to ohigh .
XHaveexcess engin eoil siphoned off .
For Engine OilLevelIgnitionMustBe On
The ignition is switched off .
XTurn theSmartKey to position 2in th eignition loc k (Ypage 124).
or
XOn vehicles wit hKEYLESS-GO ,press th eStart/Sto pbutto ntwice
(Ypage 124).
Nee dMor eTim etoCheck Engine OilLevel
The require dwaiting period was no tobserved.
XIf th eengin eis at normal operating temperature: repeat th emeas -
uremen tafter about fiv eminutes.
If th eengin eis no tat normal operating temperature, e.g. if th e
engin ewas only started briefly: repeat th emeasuremen tafter
approximately 30 minutes.
Engine Oil LevelNotMeasurabl ewithEngine Runnin g
The engineis running; oil level measuremen tis no tpossible.
XSwitc hoff th eengine.
XIf th eengin eis at normal operating temperature: wait about fiv e
minute sbefore carryin gout th emeasurement.
If th eengin eis no tat normal operating temperature, e.g. if th e
engin ewas only started briefly: wait approximately 30 minute s
before carryin gout th emeasurement.
Adding engine oil
HEnvironmenta lnot e
Whe naddin goil, tak ecar eno tto spil lany. If
oil enters th esoil or waterways, it is harmful to
th eenvironment.
!Use only engin eoils and oil filters that are
approve dfor vehicles wit h aservic esystem. A
list of th eengin eoils and oil filters that hav e
been tested and approve din accordanc ewit h
Mercedes-Ben zSpecification sfor Service
Products is available at any authorize d
Mercedes-Ben zCenter.
The followin gcaus eengin efailure or damag e
to th eexhaust system:
RUse of engin eoils and oil filters that hav e
no tbeen expressl yapprove dfor th eservic e
system
RReplacement of engin eoil and oil filter after
th ereplacemen tinterval specified by th e
servic esystem has expired
RUse of engin eoil additive s
!Do notadd to omuc hoil. addin gto omuc h
engin eoil can result in damag eto th eengin e
or to th ecatalytic converter. Hav eexcess
engin eoil siphoned off .
Example: addingengin eoil
XTurn cap :counter-clockwise and remove it .
XAddengin eoil.
If th eoil level is at or belo wtheMIN mar kon
th eoil dipstick ,add 1. 1US qt (1.0 lite r) of
engi ne oil.
Engine compartment275
Maintenance and care
Z

XReplacecap :on th efiller neck and tighten
clockwise.
Ensur ethat th ecap locks int oplac esecurely.
XChec kth eoil level again usin gth eoil dipstick
(except Mercedes-AM G S65) (Ypage 274).
XChec kth eoil level again wit hth eon-board
computer (Ypage 274).
Further information on engin eoil (
Ypage 331).
Additional service products
Important safety notes
GWARNIN G
Certain component sin th eengin ecompart-
ment, suc has th eengine, radiato rand part s
of th eexhaust system, can become ver yhot .
Workin gin th eengin ecompartmen tposes a
ris kof injury.
Wher epossible, let th eengin ecool down and
touch only th ecomponent sdescribe din th e
following.
GWARNIN G
The engin ecompartmen tcontain smoving
components. Certain components, suc has
th eradiato rfan ,may continue to run or start
again suddenly when th eignition is off .There
is aris kof injury.
If you need to do any wor kinside th eengin e
compartment:
Rswitch off th eignition
Rnever reac hint oth earea wher ethere is a
ris kof danger from moving components,
suc has th efan rotation area
Rremove jewelr yand watches
Rkeep items of clothing and hair ,for exam-
ple, away from moving part s
GWARNING
The coolin gsystem is pressurized, particularly
when th emotor is warm .If you open th ecap ,
you could be scalded if hot coolan tsprays out .
There is aris kof injury.
Let th eengin ecool down before you open th e
cap .Wear gloves and eye protection .Slowly
open th ecap to reliev epressure.
GWARNIN G
Opening th ehoo dwhen th eengin eis over-
heated or when there is afir ein th eengin e
compartmen tcould expos eyou to hot gase s
or other servic eproducts .There is aris kof
injury.
Let an overheate dengin ecool down before
opening th ehood. If there is afir ein th e
engin ecompartment, keep th ehoo dclosed
and contact th efir edepartment.
Checking coolant level
GWARNIN G
Certain component sin th eengin ecompart-
ment, suc has th eengine, radiato rand part s
of th eexhaust system, can become ver yhot .
Workin gin th eengin ecompartmen tposes a
ris kof injury.
Wher epossible, let th eengin ecool down and
touch only th ecomponent sdescribe din th e
following.
GWARNIN G
The coolin gsystem is pressurized, particularly
when th emotor is warm .If you open th ecap ,
you could be scalded if hot coolan tsprays out .
There is aris kof injury.
Let th eengin ecool down before you open th e
cap .Wear gloves and eye protection .Slowly
open th ecap to reliev epressure.
276Engine compartment
Maintenance and care

Example: checking the coolant level
XPark the vehicle on a level surface.
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down.
XTurn the SmartKey to position2in the ignition
lock (Ypage 124).
or
XOn vehicles with KEYLESS-GO, press the
Start/Stop button twice (Ypage 124).
XCheck the coolant temperature display in the
instrument cluster (Ypage 188).
The coolant temperature must be below
158 ‡ (70 †).
XTurn the SmartKey to position 0in the ignition
lock (Ypage 124).
or
XPress the Start/Stop button once on vehicles
with KEYLESS-GO (Ypage 124).
XSlowly turn cap :counter-clockwise and to
relieve excess pressure.
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 filler neck
when warm, there is enough coolant in expan-
sion 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 fu rther i
nformation on coolant, see
(Ypage 332).
Adding washer fluid to the windshield
washer system
GWARNING
Windshield washer concentrate could ignite if it comes into contact with hot engine compo-
nents or the exhaust system. There is a risk of
fire and injury.
Make sure that no windshield washer con-
centrate is spilled next to the filler neck.
Example: adding fluid to the windshield
washer system
XTo open: pull cap:upwards by the tab.
XPlace cap :on the edge of the filler neck and
engage in place.
XAdd the premixed washer fluid.
XTo close: press cap :onto the filler neck
until it engages.
If the washer fluid level drops below the recom-
mended minimum fluid level of 1.1 US qt (1.0 l),
a message appears in the multifunction display
prompting you to add washer fluid (
Ypage 230).
Further information on washer fluid
(
Ypage 333).
ASSYST PLUS
Service message
The ASSYST PLUS service interval display
informs you of the next service due date.
Information on the type of service and service
intervals (see the separate Maintenance Book-
let).
Further information can be obtained at a quali-
fied specialist workshop, e.g. an authorized
ASSYST PLUS277
Maintenance and care
Z

Mercedes-Benz Center, or at
http://www.mbusa.com (USA only).
iThe ASSYST PLUS service interval display
does not show any information on the engine
oil level. Observe the notes on the engine oil
level (
Ypage 274).
The multifunction display shows a service mes-
sage for several seconds, e.g.:
RService A in XX Days
RService A Due
RService A Overdue by XX Days
Depending on the operating conditions of the
vehicle, the remaining time or distance until the next service due date is displayed.
The letter A
orB, possibly in connection with a
number or another letter, indicates the type of
service. A
stands for a minor service and Bfor a
major service.
You can obtain further information from an
authorized Mercedes-Benz Center.
The ASSYST PLUS service interval display does
not take into account any periods of time during
which the battery is disconnected.
Maintaining the time-dependent service sched-
ule:
XNote down the service due date displayed in
the multifunction display before disconnect-
ing the battery.
or
XAfter reconnecting the battery, subtract the
battery disconnection periods from the ser-
vice date shown on the display.
Hiding a service message
XPress the aor% button on the steering
wheel.
Displaying service messages
XSwitch the ignition on.
XUse ò on the steering wheel to call up the
list of menus.
XPress 9or: on the steering wheel to
select the Servicemenu and confirm with
a.
XPress 9or: on the steering wheel to
select the ASSYST PLUSsubmenu and con-
firm with a.
The service due date appears in the multi-
function display.
Information about Service
Resetting the ASSYST PLUS service
interval display
!If the ASSYST PLUS service interval display
has been inadvertently reset, this setting can
be corrected at a qualified specialist work-
shop.
Have service work carried out as described in
the Maintenance Booklet. This may otherwise
lead to increased wear and damage to the
major assemblies or the vehicle.
A qualified specialist workshop, e.g. an author-
ized Mercedes-Benz Center, will reset the
ASSYST PLUS service interval display after the
service work has been carried out. You can also
obtain further information on maintenance
work, for example.
Special service requirements
The specified maintenance interval takes only
the normal operation of the vehicle into
account. Under arduous operating conditions or
increased load on the vehicle, maintenance
work must be carried out more frequently, for
example:
Rregular city driving with frequent intermediate
stops
Rif the vehicle is primarily used to travel short
distances
Ruse in mountainous terrain or on poor road
surfaces
Rif the engine is often left idling for long periods
Under these or similar conditions, have, for
example, the air filter, engine oil and oil filter
replaced or changed more frequently. Under
arduous operating conditions, the tires must be
checked more often. Further information can be obtained at a qualified specialist workshop, e.g.
an authorized Mercedes-Benz Center.
278ASSYST PLUS
Maintenance and care

RIt is particularly important to observe the described order when connecting and disconnecting
the jumper cables.
RNever connect or disconnect the battery terminals while the engine is running.
GWARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting the
vehicle or charging the battery, gases can escape from the battery. There is a risk of an explosion. Allow the frozen battery to thaw out before charging it or jump-starting.
If, at low temperatures, the indicator lamps/warning lamps in the instrument cluster do not light up,
it is highly likely that the discharged battery has frozen. In this case, you may neither charge the
battery nor jump-start the vehicle. The service life of a thawed-out battery may be shorter. The
starting characteristics can be impaired, particularly at low temperatures. Have the thawed-out
battery checked at a qualified specialist workshop.
!Avoid repeated and lengthy starting attempts. Otherwise, the catalytic converter could be
damaged by the non-combusted fuel.
Do not start the vehicle using a rapid charging device. If your vehicle's battery is discharged, the
engine can be jump-started from another vehicle or from a second battery using jumper cables.
Observe the following points:
RThe battery is not accessible in all vehicles. If the other vehicle's battery is not accessible, jump-
start the vehicle using a second battery or a jump-starting device.
RYou may only jump-start the vehicle when the engine and exhaust system are cold.
RJump-starting may be performed only using batteries with a nominal voltage of 12 V.
ROnly use jumper cables which have a sufficient cross-section and insulated terminal clamps.
RIf the battery is fully discharged, leave the battery that is being used to jump-start connected for
a few minutes before attempting to start. This charges the battery slightly.
RMake sure that the two vehicles do not touch.
Make sure that:
Rthe jumper cables are not damaged.
Rwhen the jumper cables are connected to the battery, uninsulated sections of the terminal clamp
do not come into contact with other metal sections.
Rthe jumper cables cannot come into contact with parts which can move when the engine is
running, such as the V-belt pulley or the fan.
XSecure the vehicle by applying the electric parking brake.
XShift the transmission to position P.
XMake sure that the ignition is switched off. All indicator lamps in the instrument cluster must be
off. When using the SmartKey, turn the SmartKey to position 0in the ignition lock and remove it
(
Ypage 124).
XSwitch off all electrical consumers, e.g. rear window defroster, lighting, etc.
XOpen the hood.
Jump-starting295
Breakdown assistance
Z

Example: ground point cover
XTurn fasteners:one Õturn and remove.
XRemove the cover while pressing down on cap ;of the washer fluid reservoir.
Position number Didentifies the charged battery of the other vehicle or an equivalent jump-starting
device.
XSlide cover Cof positive terminal =in the direction of the arrow.
XConnect positive terminal =on your vehicle to positive terminal ?of donor battery Dusing the
jumper cable. Always begin with positive terminal =on your own vehicle first.
XStart the engine of the donor vehicle and run it at idling speed.
XConnect negative terminal Aof donor battery Dto ground point Bof your vehicle using the
jumper cable, connecting the jumper cable to donor battery Dfirst.
XStart the engine.
XBefore disconnecting the jumper cables, let the engine run for several minutes.
XFirst, remove the jumper cables from ground point Band negative terminal A, then from pos-
itive clamp =and positive terminal ?. Begin each time at the contacts on your own vehicle first.
XAfter removing the jumper cables, close cover Cof positive terminal =.
XReplace the ground point cover. Make sure all mountings for the fasteners are positioned pre-
cisely beneath the corresponding recesses in the cover.
XPress fasteners:into the mountings. Turn the fasteners by Õof a turn to engage.
XHave the battery checked at a qualified specialist workshop.
296Jump-starting
Breakdo wn assis tance