2017 MERCEDES-BENZ GLC COUPE check engine

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
F!NF (USA only), !(Canada only): the red indicator lamp for the electric
parking brake flashes or is lit and/or the yellow warning lamp for the electric
parking brake is lit.
XObserve the additional display messages in the multifunction display.
6N The red restraint system warning lamp is lit while the engine is running.
The restraint system is malfunctioning.
GWARNING
The air bags or Emergency Tensioning Devices may either be triggered uninten-
tionally or, in the event of an accident, may not be triggered.
There is an increased risk of injury.
XObserve the additional display messages in the multifunction display.
XDrive on carefully.
XContact a qualified specialist workshop and have the restraint system checked.
For further information about the restraint system, see (
Ypage 42).
Warning and indicator lamps in the instrument cluster257
On-board computer and displays
Z

Engine
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
;NThe yellow Check Engine warning lamp lights up while the engine is running.
There may be a malfunction, for example:
Rin the engine management
Rin the fuel injection system
Rin the exhaust system
Rin the ignition system (for vehicles with gasoline engines)
Rin the fuel system
The emission limit values may be exceeded and the engine may be in emergency
mode.
XVisit a qualified specialist workshop immediately.
In some states, you must immediately visit a qualified specialist workshop as soon as the yellow Check Engine warning lamp lights up. This is due to the legal require-
ments in effect in these states. If in doubt, check whether such legal regulations
apply in the state in which you are currently driving.
Vehicles with a diesel engine: the fuel tank has been run dry (
Ypage 146).
XStart the engine three to four times after refueling.
If the yellow Check Engine warning lamp goes out, emergency running mode is
canceled. The vehicle need not be checked.
8N The yellow reserve fuel warning lamp lights up while the engine is running.
The fuel level has dropped into the reserve range.
XRefuel at the nearest gas station.
8N The yellow reserve fuel warning lamp flashes while the vehicle is in motion.
In addition, the ;Check Engine warning lamp may light up.
The fuel filler cap is not closed correctly or the fuel system is leaking.
XCheck that the fuel filler cap is correctly closed.
XIf the fuel filler cap is not correctly closed: close the fuel filler cap.
XIf the fuel filler cap is closed:visit a qualified specialist workshop.
?NThe red coolant warning lamp lights up while the engine is running and the
coolant temperature gauge is at the start of the scale.
The temperature sensor for the coolant temperature gauge is malfunctioning.
The coolant temperature is no longer being monitored. There is a risk of engine
damage if the coolant temperature is too high.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions. Do not continue driving under any circumstances.
XSecure the vehicle against rolling away (Ypage 149).
XConsult a qualified specialist workshop.
258Warning and indicator lamps in the instrument cluster
On-board computer and displays

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 149).
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 303).
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 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 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 149).
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 303).
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 cluster259
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.
262Warning and indicator lamps in the instrument cluster
On-board computer and displays

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 approximately 30 minutes before carrying out the measurement
Checking the oil level using the oil dip-
stick
Check the oil level with the oil dipstick (exam-
ple)
XPull oil dipstick :out of the dipstick guide
tube.
XWipe off oil dipstick :.
XSlowly slide dipstick :into the guide tube to
the stop, and take it out again after approx-
imately three seconds.
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.
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.
Add engine oil (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 l)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 302).
Further information on engine oil (
Ypage 361).
Additional service products
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.
302Engine compartment
Maintenance and care

Where possible, let the engine cool down andtouch 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
The cooling system is pressurized, particularly
when the motor is warm. If you open the cap,
you could be scalded if hot coolant sprays out.
There is a risk of injury.
Let the engine cool down before you open the
cap. Wear gloves and eye protection. Slowly
open the cap to relieve pressure.
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.
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.
Checking coolant level
Checking the coolant level (example)
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 position 2in the igni-
tion lock (Ypage 127).
or
XPress the Start/Stop button twice on vehicles
with KEYLESS-GO or the KEYLESS-GO start
function (
Ypage 128).
XCheck the coolant temperature display in the
instrument cluster (Ypage 35).
The coolant temperature must be below
158 ‡ (70 †).
XTurn the SmartKey to position gin the igni-
tion lock (Ypage 127).
or
XPress the Start/Stop button once on vehicles with KEYLESS-GO or the KEYLESS-GO start
function (
Ypage 128).
XSlowly turn cap :half a turn counter-clock-
wise and 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 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 further information on coolant, see
(
Ypage 362).
Engine compartment303
Maintenance and care
Z

Flat tire
Preparing the vehicle
Your vehiclemay be equipped with:
RMOExtended tires (tires wit hrun-flat proper -
ties) (Ypage 315)
Vehicl epreparation is no tnecessar yon vehi-
cle swit hMOExtended tires
RaTIREFI Tkit (Ypage 314)
Vehicles equipped wit hMOExtended tires are
no tequipped wit h aTIREFI Tkit at th efactory. It
is therefor erecommended that you additionally
equip your vehicl ewit h a TIREFI Tkit if you moun t
tires that do no tfeature run-flat properties, e.g.
winte rtires . ATIREFI Tkit may be obtained from
a qualified specialist workshop.
Information on changing and mounting wheels
(
Ypage 351).
XStop th evehicl eon solid, non-slippery and
leve lground ,as far away as possible from
traffic.
XSwitc hon th ehazard warning lamps.
XSecur eth evehicl eagainst rollin gaway
(Ypage 149).
XIf possible ,brin gth efron twheels int oth e
straight-ahead position .
XSwitchoff th eengine.
XRemove th eSmartKey from th eignition lock.
or, in vehicles wit hKEYLESS-GO start-function
or KEYLESS‑ GO
XOpen thedriver' sdoor .
The vehicl eelectronics are no win position
u. This means: "Key removed".
XRemove th eStart/Sto pbutto nfrom th eigni-
ti on loc k (Ypage 128).
XMakesure that th eengin ecanno tbe started
via your smartphon e (Ypage 129).
XMakesure that th epassenger sare no tendan -
gered as they do so. Mak esure that no on eis
near th edanger area while awhee lis bein g
changed. Anyon ewho is no tdirectly assisting
in th ewhee lchang eshould, for example ,
stand behind th ebarrier.
XGet out of th evehicle. Pay attention to traffic
condition swhen doin gso.
XClose th edriver' sdoor .
Vehicles with MOExtended tires (tires
with run-flat characteristics)
General notes
Wit hMOExtended tires (tires wit hrun flat char-
acteristics), you can continue to driv eyour vehi-
cle eve nif there is atotal loss of pressur ein on e
or mor etires .The affected tire must no tsho w
any clearly visible damage.
You can recognize aMOExtended tire by th e
MOExtended markin gwhic happear son th e
sidewall of th etire. You will fin dthis markin g
next to th etire siz edesignation ,th eload-bear -
ing capacit yand th espee dindex (
Ypage 345).
MOExtended tires may only be used in conjunc -
tion wit han active tire pressur eloss warning
system or wit han active tire pressur emonitor.
If apressure loss warning messag eappears
in th emultifunction display:
Robserv eth einstruction sin th edisplay mes -
sage s (Ypage 245).
Rcheck th etire for damag e
Rif driving on,observ eth efollowin gnote s
The driving distanc epossible in run-flat mod eis
approximately 50 mile s(80 km) when th evehi-
cle is partially laden .When th evehicl eis fully
laden it is approximately 19 mile s(30 km).
In addition to th evehicl eload, th edriving dis-
tance possible depend supon :
RVehicl espee d
RRoad condition
ROutside temperature
The driving distanc epossible in run-flat mod e
may be reduce dby extreme driv ing condi
tion
s
or maneuvers, or it can be increased throug h a
moderat estyle of driving .
The driving distanc epossible in run-flat mod eis
counted from th emomen tth etire pressur eloss
warning appear sin th emultifunction display.
You must no texcee d amaximum permissible
spee dof 50 mph (80 km/h).
When replacing on eor all tires ,pleas eobserv e
th efollowin gspecification sfor your vehicle's
tires :
Rsize
Rthetyp eand
Rth e"MOExtended" markin g
If atire has gon eflat and canno tbe replace d
wit h a MOExtended tire, astandard tire may be
used as atemporar ymeasure. Mak esure that
Flat tire315
Breakdown assistance

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.
All vehicles:
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, please observe the fol-
lowing:
RSecure the vehicle to prevent it from rolling
away.
RSwitch off the ignition.
RDisconnect the negative terminal first and
then the positive terminal.
The transmission is locked in position j
after disconnecting the battery.
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.
Electrolyte or battery acid is corro-
sive. Avoid contact with skin, eyes or
clothing.
Wear suitable protective clothing,
especially gloves, apron and face-
guard.
Immediately rinse electrolyte or acid
splashes off with clean water. Con-
tact 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
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.
320Battery (vehicle)
Breakdown assistance