check engine light MERCEDES-BENZ GLC COUPE 2018 User Guide

ProblemPossible causes/consequences andMSolutions
The engine is not running
smoothly and is misfir-
ing.There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
XOnly depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic converter
and damage it.
XHave the cause rectified immediately at a qualified specialist work-
shop.
The coolant temperature
display indicates a value
within the red band.The coolant level is too low. The coolant is too hot and the engine is no
longer being cooled sufficiently.
XStop as soon as possible and allow the engine and the coolant to
cool down.
XCheck the coolant level (Ypage 306). Observe the warning notes
as you do so and add coolant if necessary.
DYNAMIC SELECT switch
Mercedes-AMG vehicles
General information
Use the DYNAMIC SELECT switch to select the
drive program.
Available drive programs for Mercedes-
AMG GLC 43 4MATIC:
S+ Sport PlusParticularly sporty driving
characteristics
SSportSporty driving characteris-
tics
C ComfortComfortable and economi-
cal driving characteristics
EEconomyParticularly economical
driving characteristics
IIndividualIndividual settings
Available drive programs for Mercedes-
AMG GLC 63 4MATIC+/GLC 63 S 4MATIC+:
RACE
(S‑MODEL)Driving characteristics suit-
able for a race circuit
S+ Sport PlusParticularly sporty driving
characteristics
SSportSporty driving characteris-
tics
C ComfortComfortable and economi-
cal driving characteristics
IIndividualIndividual settings
Depending on the drive program selected the
following vehicle characteristics will change:
Rthe drive (engine and transmission manage-
ment)
Rthe suspension
Rthe steering
Rthe driver assistance systems
RESP®(Mercedes-AMG GLC 63 4MATIC+/
GLC 63 S 4MATIC+)
Rthe position of the exhaust flap (Mercedes-
AMG GLC 63 4MATIC+/GLC 63 S 4MATIC+)
Rthe setting of the ECO start/stop function
Rthe availability of gliding mode
Rthe climate control
Further information for automatic drive program
characteristics (
Ypage 144).
Additionally, in drive program Iyou can config-
ure the respective vehicle characteristics using
the multimedia system. You can find informa-
tion about this under "DYNAMIC SELECT" in the
vehicle's Digital Operator's Manual.
Each time you start the engine with the Smart-
Key or the Start/Stop button, drive program Cis
activated. Further information about starting
the engine (
Ypage 132).
138DYNAMIC SELECT switch
Driving and parking

This helps you to avoid overheating the
brakes and wearing them out excessively.
When you take advantage of engine braking, a
drive wheel may not turn for some time, e.g.
on a slippery road surface. This could cause
damage to the drive train. This type of damage is not covered by the Mercedes-Benz war-
ranty.
Heavy and light loads
GWARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This increases the stopping distance and can even
cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time.
!Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately. Drive
on for a short while. This allows the airflow to
cool the brakes more quickly.
Wet roads
If you have driven for a long time in heavy rain
without braking, there may be a delayed reac-
tion from the brakes when braking for the first
time. This may also occur after the vehicle has
been washed or driven through deep water.
You have to depress the brake pedal more
firmly. Maintain a greater distance from the
vehicle in front.
After driving on a wet road or having the vehicle
washed, brake firmly while paying attention to
the traffic conditions. This will warm up the
brake discs, thereby drying them more quickly
and protecting them against corrosion.
Limited braking performance on salt-
treated roads
If you drive on salted roads, a layer of salt resi-
due may form on the brake discs and brake
pads. This can result in a significantly longer
braking distance.
RIn order to prevent any salt build-up, apply the
brakes occasionally while paying attention to
the traffic conditions.
RCarefully depress the brake pedal and the
beginning and end of a journey.
RMaintain a greater distance to the vehicle
ahead.
Servicing the brakes
!The brake fluid level may be too low, if:
Rif the red brake warning lamp lights up in
the instrument cluster and
Ryou hear a warning tone while the engine is
running
Observe additional warning messages in the
multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked immediately.
Consult a qualified specialist workshop to
arrange this.
!Vehicles with 4MATIC: function or per-
formance tests may only be carried out on a 2-
axle dynamometer. If you wish to operate the
vehicle on such a dynamometer, please con-
sult a qualified specialist workshop in
advance. You could otherwise damage the
drive train or the brake system.
!Vehicles with 4MATIC: the ESP®system
operates automatically. If the electric parking
brake is tested on a brake dynamometer, the
engine and ignition must be switched off: turn
the SmartKey in the ignition lock to position
u or1 or press the Start/Stop button
repeatedly in accordance with the given
SmartKey positions.
Braking triggered automatically by ESP
®may
cause severe damage to the brake system.
All checks and maintenance work on the brake
system must be carried out at a qualified spe-
cialist workshop.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
If the brake system has only been subject to
moderate loads, you should test the functional-
ity of your brakes at regular intervals.
Information on BAS (Brake Assist System)
(
Ypage 66) and Active Brake Assist with cross-
traffic function (Ypage 72).
Driving tips157
Driving and parking
Z

Rif there is a sudden change in temperature,
e.g. when driving into a heated garage in win-ter
Rif the camera lens is dirty or obstructed.
Observe the notes on cleaning
(
Ypage 312)
Rif the rear of your vehicle is damaged. In this
case, have the camera position and setting
checked at a qualified specialist workshop
The field of vision and other functions of the rear
view camera may be restricted due to additional
accessories on the rear of the vehicle (e.g.
license plate holder, rear bicycle rack).
The rear view camera is protected from rain-
drops and dust by means of a flap. When the rear view camera is activated, this flap opens.
The flap closes again when:
Ryou have finished the maneuvering process
Ryou switch off the engine
Ryou open the cargo compartment
Observe the notes on cleaning (
Ypage 312).
For technical reasons, the flap may remain open
briefly after the rear view camera has been
deactivated.
Activating/deactivating the rear view
camera
XTo activate: make sure that the Activa‐
tion by R gearfunction is selected in the
multimedia system (see the Digital Operator's
Manual).
XEngage reverse gear.
The rear view camera flap opens. The multi-
media system shows the area behind the vehi-
cle with guide lines.
The image from the rear view camera is avail- able throughout the maneuvering process.
XTo switch the function mode for vehicles
with trailer tow hitch: using the controller,
select symbol :for the "Reverse parking"
function or symbol ;for "Coupling up a
trailer".
The symbol of the selected function is high-
lighted.
XTo deactivate: shift the transmission to posi-
tion j.
or
XDrive forwards at a speed greater than 7 mph
(12 km/h).
Multimedia display
The rear view camera may show a distorted view
of obstacles, show them incorrectly or not at all.
The rear view camera does not show objects in
the following positions:
Rvery close to the rear bumper
Runder the rear bumper
Rin the area immediately above the tailgate
handle
!Objects not at ground level may appear to
be further away than they actually are, e.g.:
Rthe bumper of a parked vehicle
Rthe drawbar of a trailer
Rthe ball coupling of a trailer tow hitch
Rthe rear section of an HGV
Ra slanted post
Use the guidelines only for orientation.
Approach objects no further than the bottom-
most guideline.
Driving systems181
Driving and parking
Z

Warning lamp
:Warning lamp
Blind Spot Assist is not active at speeds below
approximately 20 mph (30 km/h). Vehicles in
the monitoring range are then not indicated.
If a vehicle is detected within the blind spot
monitoring range at speeds above 20 mph
(30 km/h), warning lamp :on the correspond-
ing side lights up red. This warning is always
emitted when a vehicle enters the blind spot
monitoring range from behind or from the side.
When you overtake a vehicle, the warning only
occurs if the difference in speed is less than
7 mph (12 km/h).
If you select the reverse gear, Blind Spot Assist is not operational.
The brightness of the warning lamps is auto-
matically adapted to the brightness of the sur-
roundings.
Collision warning
If a vehicle is detected in the monitoring range of
Blind Spot Assist and you switch on the corre-
sponding turn signal, a double warning tone
sounds. The red warning lamp flashes on the
relevant exterior mirror. If the turn signal
remains on, detected vehicles are indicated by
the flashing of the red warning lamp on the exte-
rior mirror. There are no further warning tones.
Activating Blind Spot Assist
XMake sure that Blind Spot Assist is activated
in the on-board computer (Ypage 218).
XTurn the SmartKey to position 2in the igni-
tion lock.
The red warning lamps on the exterior mirrors
light up until the engine is started.
Display in the assistance graphic
When Blind Spot Assist is activated, gray radar
waves propagating backwards appear next to
the vehicle in the assistance display in the mul-
tifunction display (
Ypage 217). Above a speed
of 20 mph (30 km/h), the color of the radar
waves in the assistance graphic changes to
green :. Blind Spot Assist is then ready for use.
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical connection.
This can be accomplished by checking the trailer
lighting. In this event, Blind Spot Assist is deac-
tivated. The Blind
SpotAssistNotAvail‐able When Towing a Trailer See Opera‐tor's Manualmessage appears in the multi-
function display.
Lane Keeping Assist
General notes
Lane Keeping Assist monitors the area in front of
your vehicle by means of multifunction cam-
era :which is attached behind the top of the
windshield. Active Lane Keeping Assist detects
lane markings on the road and can warn you
before you leave your lane unintentionally.
Driving systems193
Driving and parking
Z

the lines on the assistance graphic display are
shown in green (Ypage 217). Active Lane
Keeping Assist is ready for use.
XTo deactivate: press button;.
Indicator lamp :goes out. The Active Lane
Keeping Assist is deactivated. The Lane
Keeping Assist Offmessage appears in
the multifunction display.
Selecting Standard or Adaptive setting
XIn the DriveAssistmenu on the on-board
computer, select the Active Lane Keep‐
ing Assistfunction (Ypage 219).
XSelect settingStandardorAdaptive.
When Standardis selected, no warning vibra-
tion occurs if:
Ryou switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time
Ra driving safety system intervenes, such as
ABS, BAS or ESP®
When Adaptiveis selected, no warning vibra-
tion occurs if:
Ryou switch on the turn signals. In this event, the warnings are suppressed for a certain
period of time.
Ra driving safety system intervenes, e.g.
ABS, BAS or ESP®
Ryou accelerate hard, e.g. kickdown.
Ryou brake hard
Ryou steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly
Ryou cut the corner on a sharp bend
To ensure that you are warned only when nec-
essary and in good time if you cross the lane
markings, the system detects certain conditions
and warns you accordingly.
The warning vibration occurs earlier if:
Ryou approach the outer lane marking on a
bend
Rthe road has very wide lanes, e.g. a freeway
Rthe system detects solid lane markings
The warning vibration occurs later if:
Rthe road has narrow lanes
Ryou cut the corner on a bend
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical connection. This can be accomplished by checking the trailer
lighting.
Towing a trailer
Important safety notes
GWARNING
Installing an unsuitable ball coupling may
result in overloading of the trailer tow hitch
and the rear axle. This applies especially if the ball coupling in question is longer or angled
differently. This could seriously impair the
driving characteristics and the trailer can
come loose. There is a risk of an accident.
You should only ever install a ball coupling
that has the permissible dimensions and that
is designed to meet your trailer-towing
requirements. Do not modify the ball coupling
or the trailer tow hitch.
You will find the values approved by the manu-
facturer on the vehicle identification plates and
those for the towing vehicle under "Technical
data" (
Ypage 367).
GWARNING
When the vehicle/trailer combination begins
to lurch, you could lose control of it. The vehi- cle/trailer combination could even rollover.
There is a risk of an accident.
On no account should you attempt to
straighten up the vehicle/trailer combination
by increasing the speed. Reduce vehicle
speed and do not countersteer. Apply the
brake as necessary.
!If you have a trailer tow hitch retrofitted,
changes to the engine cooling system may be
necessary, depending on the vehicle type.
If you have a trailer tow hitch retrofitted,
observe the anchorage points on the chassis
frame.
The installation of a trailer tow hitch is only per-
missible if a towing weight is specified in your
vehicle documents. If this is not the case, then
the vehicle is not approved for the towing of a
trailer.
200Towing a trailer
Driving an d parking

XSwitch off the engine.
XClose the doors and tailgate.
XCouple up the trailer.
XEstablish the electrical connection between
the vehicle and the trailer.
XCheck that the trailer lighting system is work-
ing.
XPush the combination switch upwards/down-wards and check whether the corresponding
turn signal on the trailer flashes.
A trailer that is connected is recognized only
when the electrical connection is established
correctly and when the lighting system is work-
ing properly. The function of other systems also
depends on this, for example:
RESP®
RPARKTRONIC
RActive Parking Assist
RActive Blind Spot Assist
RActive Lane Keeping Assist
Vehicles with AIR BODY CONTROL: if you couple
up a trailer, the vehicle always remains at high-
way level. Observe the following note when cou-
pling up a trailer:
RUnless highway level has been set manually,
the vehicle is automatically lowered to high-
way level. If a speed of 5 mph (8 km/h) has
been reached, this may be the case.
These restrictions apply to accessories that are
supplied with power via the trailer socket in your
vehicle, e.g. a rear bicycle rack.
Observe the maximum permissible trailer
dimensions (width and length).
Most U.S. states and all Canadian provinces
require by law:
RSafety chains between the towing vehicle and
the trailer. The chains should be cross-wound
under the trailer drawbar. They must be fas-
tened to the vehicle's trailer coupling, not to
the bumper or the axle.
Leave enough play in the chains to make tight
cornering possible.
RA separate brake system for certain types of
trailer.
RSafety switch for braked trailers. Check the
specific legal requirements applicable to your state.
If the trailer becomes detached from the tow-
ing vehicle, the safety feature applies the
trailer brakes.
Towing a trailer
There are several legal requirements for towing
a trailer, e.g. the maximum permissible speed.
Make sure that your car/trailer combination
complies with the local regulations:
Rin your place of residence
Rat your destination
The police and local authorities can provide reli- able information.
To accumulate driving experience and accustom
yourself to the new handling characteristics,
practice the following at a location where there
is no traffic:
RCornering
RStopping
RBacking up
Check the following before the journey:
RTrailer tow hitch
RSafety switch for braked trailers
RSafety chains
RElectrical connections
RLighting system
RWheels and tires
RLoad securing
Adjust the exterior mirrors so that you have a
clear view of the rear section of the trailer.
If the trailer is equipped with electronically con-
trolled brakes, pull away carefully in the car/
trailer combination. Brake manually using the
brake controller and check whether the brakes
function correctly.
Regularly check that the load is secure.
When towing a trailer, your vehicle's handling
characteristics will be different in comparison
with when driving without a trailer.
The vehicle/trailer combination:
Ris heavier
Ris restricted in its acceleration and gradient-
climbing capability
Rhas an increased braking distance
Ris affected more by strong crosswinds
Rdemands more sensitive steering
Rhas a larger turning circle
Avoid sudden steering movements.
Avoid braking abruptly. If possible, brake gently
at first to allow the trailer to run on. Then,
increase the braking force rapidly.
Towing a trailer203
Driving and parking
Z

Display messagesPossible causes/consequences andMSolutions
The yellow!warning lamp lights up and th ered F (USAonly)
or ! (Canada only) indicator lamp flashes .
It is no tpossibl eto apply th eelectric parking brak emanually.
XShift th etransmission to position j.
XVisitaqualified specialist workshop .
$(USAonly)
J(Canada only)
Check Brake Fluid
Level
There is no tenough brak eflui din th ebrak efluid reservoir .
In addition ,th e$ (USAonly) or J(Canada only) warning lamp
lights up in th einstrumen tcluste rand awarning tone sounds.
GWARNIN G
The braking effec tmay be impaired.
There is aris kof an accident.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions. Do no tcontinu edrivin g
under any circumstances.
XSecur eth evehicl eagainst rollin gaway (Ypage 151).
XConsult aqualified specialist workshop .
XDo notadd brak efluid .This does no tcorrec tth emalfunction .
#
CheckBrakePadWear
The brak epads/linings hav ereached their wear limit.
US Aonly: th ered $ brakesystem warning lamp is lit while th e
engin eis running.
XVisit aqualified specialist workshop .
G
Inoperative
Oneor mor emain features of th embrace system are malfunctioning .
XVisitaqualified specialist workshop .
ActiveBrakeAssistFunctionsCurrentlyLimitedSee Opera‐tor's Manual
Active Brake Assis tis temporarily inoperative.
Possibl ecauses are:
Rth eradar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation
Rth esystem is outside th eoperating temperature range
Rth eon-boar dvoltag eis to olow
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Active Brake Assis tis operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 151).
XRestart th eengine.
Display messages23 1
On-board computer and displays
Z

Display messagesPossible causes/consequences andMSolutions
#
StopVehicl eSeeOperator' sManual
The battery is no longer bein gcharged and th econdition of charg eis
to olow.
A warning tone also sounds.
XPull ove rand stop th evehicl esafely and switch off th eengine, pay-
ing attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 151).
XObserv eth einstruction sin th e# See Operator' sManualdisplay message .
XConsultaqualified specialist workshop .
#
StopVehicl eLeaveEngine Runnin g
The battery condition of charg eis to olow.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions. Do no tcontinu edrivin g
under any circumstances.
XLeav eth eengin erunning.
XWait until th edisplay message disappear sbefore pullin gaway.
#
Start Engine SeeOperator' sManual
The engin eis switched off and th econdition of charg eis to olow.
XSwitc hoff electrical consumer sthat you do no tneed, suc has th e
rear window defroste rand interior lighting .
XLeaveth eengin erunnin gfor afew minute sor drive alon gdistance.
The battery is bein gcharged.
4
CheckEngineOilAtNex tRefueling
The engin eoil level has dropped to th eminimum level.
A warning tone also sounds.
!Avoid lon gjourneys wit hto olittl eengin eoil. The engin ewill oth-
erwise be damaged.
XChec kth eoil level when next refueling, at th elatest (Ypage 305).
XIf necessary, add engin eoil (Ypage 305).
If you have to ad dengin eoil frequently:
XContac t aqualified specialist workshop and hav eth eengin e
checked.
Information on approve dengin eoils can be obtained from aqualified
specialist workshop or on th eInternet at http://bevo.mercedes -
benz.co m.
240Display messages
On-board computer and displays

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 43).
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.
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.
260Warning and indicator lamps in the instrument cluster
On-board computer and displays

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
8NThe 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 gage is at the start of the scale.
The temperature sensor for the coolant temperature gage 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 151).
XConsult a qualified specialist workshop.
Warning and indicator lamps in the instrument cluster261
On-board computer and displays
Z