check engine MERCEDES-BENZ CLS-Class 2017 W218 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 141).
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 268).
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 248 ‡
(120 †). Otherwise, the engine could be damaged.
XDrive to the nearest qualified specialist workshop.
XAvoid subjecting the engine to heavy loads, 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 248 ‡(120 †). 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 141).
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 268).
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 cluster233
On-board computer and displays
Z

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.
266Engine compartment
Maintenance and care

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 0.8 US qt (0.8 liters) of oil per
600 miles (1,000 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
Example
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 liter) of engine oil.
Adding engine oil
HEnvironmental note
When adding oil, take care not to spill any. If
oil enters the soil or waterways, it is harmful to
the environment.
!Use only engine oils and oil filters that are
approved for vehicles with a service system. A list of the engine oils and oil filters that have
been tested and approved in accordance with
Mercedes-Benz Specifications for Service
Products is available at any authorized
Mercedes-Benz Center.
The following cause engine failure or damage
to the exhaust system:
RUse of engine oils and oil filters that have
not been expressly approved for the service
system
RReplacement of engine oil and oil filter after
the replacement interval specified by the
service system has expired
RUse of engine oil additives
!Do not add too much oil. adding too much
engine oil can result in damage to the engine
or to the catalytic converter. Have excess
engine oil siphoned off.
Example
XTurn cap :counter-clockwise and remove it.
XAdd engine oil.
If the oil level is at or below 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 tighten
clockwise.
Ensure that the cap locks into place securely.
XCheck the oil level again with the oil dipstick
(Ypage 267).
Further information on engine oil (
Ypage 325).
Engine compartment267
Maintenance and care
Z

Additional service products
Import ant 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 .
Working in th eengin ecompartmen tposes a
ris kof injury.
Wher epossible, let th eengin ecool down and
touch only th ecomponent sdescribed in th e
following.
GWARNIN G
The engin ecompartmen tcontain smoving
components. Certain components, suc has
th eradiato rfan ,may continu eto 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
Exampl e
XPark thevehicl eon alevel surface.
Only chec kth ecoolan tlevel when th evehicl e
is on alevel surfac eand th eengin ehas cooled
down .
XTurn th eSmartKey to position 2in th eignition
loc k (Ypage 123).
or
XOn vehicles wit hKEYLESS-GO ,press th e
Start/Sto pbutto ntwice (Ypage 123).
XCheckth ecoolan ttemperature display in th e
instrumen tcluster.
The coolan ttemperature mus tbe belo w
15 8 ‡ (70 †).
XTurn th eSmartKey to position 0in th eignition
loc k (Ypage 123).
or
XPress th eStart/Sto pbutto nonce on vehicles
wit hKEYLESS-GO (Ypage 123).
XSlowly turncap :half atur ncounter-clock -
wise and allow excess pressur eto escape.
XTurn cap :further counter-clockwise and
remove it .
If th ecoolan tis at th elevel of marke rbar =
in th efiller neck when cold, there is enough
coolan tin coolan texpansion tan k;.
If th ecoolan tlevel is approximately 0. 6in
(1.5 cm ) above marker bar =in the filler neck
when warm, there is enough coolant in expan-
sion tank ;.
268Engine compartment
Maintenance and care

iExample: equipment and country-specific
variations possible.
Vehicles with alloy wheels and hub caps
On vehicles with alloy wheels and hub caps, a
socket is also provided.
Flat tire
Preparing the vehicle
Your vehicle may be equipped with:
RMOExtended tires (tires with run-flat proper-
ties) (Ypage 278)
Vehicle preparation is not necessary on vehi-
cles with MOExtended tires
Ra TIREFIT kit (Ypage 277)
Ran emergency spare wheel (Ypage 317)
Vehicles equipped with MOExtended tires are
not equipped with a TIREFIT kit at the factory. It
is therefore recommended that you additionally
equip your vehicle with a TIREFIT kit if you mount tires that do not feature run-flat properties, e.g.
winter tires. A TIREFIT kit may be obtained from a qualified specialist workshop.
Information on changing and mounting wheels
(
Ypage 312).
XStop the vehicle on solid, non-slippery and
level ground, as far away as possible from
traffic.
XSwitch on the hazard warning lamps.
XSecure the vehicle against rolling away
(Ypage 141).
XIf possible, bring the front wheels into the
straight-ahead position.
XVehicles with AIRMATIC: make sure that "nor-
mal" level is selected (Ypage 159).
XSwitch off the engine.
XRemove the SmartKey from the ignition lock.
or, on vehicles with KEYLESS ‑GO:
XOpen the driver's door.
The vehicle electronics now have status 0.
This is the same as the SmartKey having been
removed.
XRemove the Start/Stop button from the igni-
tion lock (Ypage 123).
XMake sure that the passengers are not endan-
gered as they do so. Make sure that no one is near the danger area while a wheel 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. Pay attention to traffic
conditions when doing so.
XClose the 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 your vehi-
cle even if there is a total loss of pressure in one
or more tires. The affected tire must not show
any clearly visible damage.
You can recognize MOExtended tires by the
MOExtended marking which appears on the
sidewall of the tire. You will find this marking
next to the tire size designation, the load-bear-
ing capacity and the speed index (
Ypage 307).
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 a pressure loss warning message appears
in the multifunction display:
Robserve the instructions in the display mes-
sages (Ypage 221).
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. When the vehicle is fully
laden it is approximately 19 miles (30 km).
In addition to the vehicle load, the driving dis-
tance possible depends upon:
RVehicle speed
RRoad condition
ROutside temperature
The driving di stance p
ossible 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 a maximum permissible
speed of 50 mph (80 km/h).
278Flat tire
Breakdown assistance

RMake sure that the positive terminal of a
connected battery does not come into con-
tact with vehicle parts.
RNever place metal objects or tools on a bat-tery.
RIt is important that you observe the descri-
bed order of the battery terminals when
connecting and disconnecting a battery.
RWhen jump-starting, make sure that the
battery poles with identical polarity are
connected.
RIt is particularly important to observe the
described order when connecting and dis-
connecting the jumper cables.
RNever connect or disconnect the battery
terminals while the engine is running.
GWARNING
Battery acid is caustic. There is a risk 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.
HEnvironmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately and recycled to protect the
environment.
Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified spe-
cialist workshop or a special
collection point for used bat-
teries.
!Have the battery checked regularly at a
qualified specialist workshop. Observe the service intervals in the Mainte-
nance Booklet or contact a qualified specialist
workshop for more information.
!Always have work on batteries carried out at
a qualified specialist workshop. Should it, in
exceptional circumstances, be absolutely
necessary to disconnect the 12-volt battery
yourself, observe the following:
Rsecure the vehicle to prevent it from rolling
away.
Rswitch off the ignition.
Ralways disconnect the negative terminal
clamp first, followed by the positive termi-
nal clamp.
After the battery has been disconnected, the
transmission is locked in position P.
After the work has been done, install the bat-
tery and replace the cover of the positive ter-
minal clamp firmly.
Comply with safety precautions and take pro-
tective measures when handling batteries.
Risk of explosion.
Fire, open flames and smoking are
prohibited when handling the bat-
tery. Avoid creating sparks.
Battery acid is caustic. Avoid contact
with skin, eyes or clothing.
Wear suitable protective clothing,
especially gloves, apron and face-
guard.
Rinse any acid spills immediately
with clear water. Contact a physician
if necessary.
Wear eye protection.
Keep children away.
Observe this Operator's Manual.
For safety reasons, Mercedes-Benz recom-
mends that you only use batteries which have
been tested and approved for your vehicle by
Battery (vehicle)283
Breakdown assistance
Z

Mercedes-Benz. These batteries provide
increased impact protection to prevent vehicle
occupants from suffering acid burns should the
battery be damaged in the event of an accident.
In order for the battery to achieve the maximum
possible service life, it must always be suffi-
ciently charged.
Like other batteries, the vehicle battery may
discharge over time if you do not use the vehicle.
In this case, have the battery disconnected at a
qualified specialist workshop. You can also
charge the battery with a charger recommended
by Mercedes-Benz. Contact a qualified special-
ist workshop for further information.
Have the battery condition of charge checked
more frequently if you use the vehicle mainly for
short trips or if you leave it standing idle for a
lengthy period. Consult a qualified specialist
workshop if you wish to leave your vehicle
parked for a long period of time.
Remove the SmartKey if you park the vehicle
and do not require any electrical consumers.
The vehicle will then use very little energy, thus conserving battery power.
If the power supply has been interrupted, e.g. if
you reconnect the battery, you will have to:
Rset the clock; see the Digital Operator's Man-
ual
On vehicles with a multimedia system, the
time is set automatically.
Rreset the function for folding the exterior mir-
rors in/out automatically, by folding the mir-
rors out once (
Ypage 101).
Charging the battery
!
Only use battery chargers with a maximum
charging voltage of 14.8 V.
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 a battery.
GWARNING
Battery acid is caustic. There is a risk 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
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing 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.
!Only charge the battery using the jump-
starting connection point.
The jump-starting connection point is in the
engine compartment (
Ypage 285).
XOpen the hood.
XConnect the battery charger to the positive
terminal and ground point in the same order
as when connecting the donor battery in the
jump-starting procedure (
Ypage 285).
Keep away from fire and open flames. Do not
lean over a battery. Never charge the battery if it
is still installed in the vehicle, unless you use a
battery charger which has been tested and
approved by Mercedes-Benz. A battery charger
unit specially adapted for Mercedes-Benz vehi-
cles and tested and approved by Mercedes-
Benz is available as an accessory. It permits the
charging of the battery in its installed position.
Contact an authorized Mercedes-Benz Center
for further information and availability. Read the
battery charger's operating instructions before
charging the battery.
If the warning and indicator lamps do not light up
on the instrument cluster when temperatures
are low, it is probably because 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.
284Battery (vehicle)
Breakdown assistance

Jump-starting
For the jump-starting procedure, use only the jump-starting connection point in the engine com-
partment, consisting of a positive terminal and a ground point.
GWARNING
Battery acid is caustic. There is a risk 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 batteries. Wash away battery acid immediately with plenty of
clean water and seek medical attention.
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 ven-
tilation while charging and jump-starting. Do not lean over a battery.
GWARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or sparks
are created, the hydrogen gas can ignite. There is a risk of an explosion.
RMake sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
RNever place metal objects or tools on a battery.
RIt is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
RWhen jump-starting, make sure that the battery poles with identical polarity are connected.
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.
!Avoid repeated and lengthy starting attempts. Otherwise, the catalytic converter could be
damaged by the non-combusted fuel.
If the indicator and warning lamps do not light up at low temperatures, it is very 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.
Jump-starting285
Breakdown assistance
Z

XConnect negative terminal?of donor battery Bto ground point Aof your vehicle using the
jumper cable, connecting the jumper cable to battery of other vehicle Bfirst.
XStart the engine.
XBefore disconnecting the jumper cables, let the engine run for several minutes.
XFirst, remove the jumper cables from ground point Aand negative terminal ?, then from pos-
itive clamp ;and positive terminal =. Begineach time at the contacts on your own vehicle first.
XClose cover :of positive clamp ;after removing the jumper cables.
XHave the battery checked at a qualified specialist workshop.
Jump-starting isnot cons idered to bea normal operating condition.
iJumper cables and further information regarding jump-starting can beobtained at any qualified
specialist workshop.
Towing and tow-starting
Important safety notes
GWARNING
Functions relevant to safety are restricted or
no longer availab leif:
Rthe engine isnot running.
Rthe brake system or the power steering is
malfunctioning.
Rthere isa malfunction inthe voltage supply
or the veh icle's electrical system.
If your veh icle is bein g towed, much more
force may benecessary to steer or brake.
There isa risk of an acc ident.
In such cases, use a tow bar. Before to wing,
make sure that the steering moves freely.
GWAR NING
When to wingor tow-starting another veh icle
and its weight isgreater than the permis sible
gross weight of your veh icle, the:
Rthe to wingeye could detach itself
Rthe veh icle/trailer co mbination could roll-
over.
There isa risk of an acc ident.
When to wingor tow-starting another veh icle,
its weight should not begreater than the per-
mis sible gross weight of your veh icle.
Details on the permis siblegross veh icleweight
of your veh iclecan befound on the veh icle iden-
tification plate (
Ypage 322).
!When Active Brake Assist, Distance Pilot
DI ST RONIC or the HOLD function isactivated,
the vehicle brakes automatically incertain
situations.
To avoid damage to the vehicle, deactivate
these systems inthe following or similar sit-
uations:
Rwhen towing the vehicle
Rin the car wash
!Only secure the tow rope or tow bar at the
towing eyes. Otherwise, the vehicle could be
damaged.
!Do not use the towing eye for recovery, th is
could damage the vehicle. If indoubt, recover
the vehicle with a crane.
!When towing, pull away slowly and
smoothly. Ifthe tractive power is too high, the
vehicles could be damaged.
!Do not tow with sling-type equipment. This
could damage the vehicle.
!When towing vehicles with KEYLESS-GO,
use the key instead of the Start /S top button.
Otherwise, the automat ictransmission may
shift to position Pwhen the driver's or front-
passenger door are opened, which could lead to damage to the transmission.
!The vehicle can betowed a maximum of
30 mile s (50km). The towing speed of 30 mph
(50 km/ h)must not be exceeded.
If the vehicle has to be towed more than
30 miles (50km), the entire vehicle must be
raised and transported.
Towing and tow-starting287
Breakdown assistance
Z

The fuses are located in various fuse boxes:
RFuse box in the engine compartment on the
left-hand side of the vehicle, when viewed in
the direction of travel
RFuse box in the trunk on the right-hand side of
the vehicle, when viewed in the direction of
travel
Fuse box in the engine compartment
Pay attention to the important safety notes
(Ypage 290).
GWARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood.
XMake sure that the windshield wipers are
turned off.
XOpen the hood (Ypage 265).
XUse a dry cloth to remove any moisture from
the fuse box.
XTo open: take lines :out of the guides.
XMove lines :to one side.
XOpen retaining clamps ;.
XRemove the fuse box cover forwards.
XTo close:check whether the seal is lying cor-
rectly in the cover.
XInsert the cover at the rear of the fuse box into
the retainer.
XFold down the cover and close clamps ;.
XSecure lines:in the guides.
XClose the hood.
Fuse box in the trunk
Pay attention to the important safety notes
(Ypage 290).
XOpen the trunk lid.
XTo open: release cover :at the top right and
left-hand sides with a flat object.
XOpen cover :downwards in the direction of
the arrow.
Fuses291
Breakdown assistance
Z