check engine MERCEDES-BENZ GLC 2018 Owner's Manual

R
if there is a sudden change in temperature,
e.g. when driving into a heated garage in win-
ter R
if the camera lens is dirty or obstructed.
Observe the notes on cleaning
( Y
page 328) R
if 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: R
you have finished the maneuvering process R
you switch off the engine R
you open the cargo compartment
Observe the notes on cleaning ( Y
page 328).
For technical reasons, the flap may remain open
briefly after the rear view camera has been
deactivated.
Activating/deactivating the rear view
camera
X
To activate: make sure that the Activa‐
tion by R gear function is selected in the
multimedia system (see the Digital Operator's
Manual). X
Engage 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. X
To switch the function mode for vehicles
with trailer tow hitch: using the controller,
select symbol C for the "Reverse parking"
function or symbol D for "Coupling up a
trailer".
The symbol of the selected function is high-
lighted. X
To deactivate: shift the transmission to posi-
tion ] .
or X
Drive 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: R
very close to the rear bumper R
under the rear bumper R
in the area immediately above the tailgate
handle
! Objects not at ground level may appear to
be further away than they actually are, e.g.: R
the bumper of a parked vehicle R
the drawbar of a trailer R
the ball coupling of a trailer tow hitch R
the rear section of an HGV R
a slanted post
Use the guidelines only for orientation.
Approach objects no further than the bottom-
most guideline.Driving systems 195
Driving and parking Z

Warning lamp
C
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 C 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 X
Make sure that Blind Spot Assist is activated
in the on-board computer ( Y
page 232).X
Turn the SmartKey to position H in 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 ( Y
page 231). Above a speed
of 20 mph (30 km/h), the color of the radar
waves in the assistance graphic changes to
green C . 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 Spot Assist Not Avail‐
able When Towing a Trailer See Opera‐
tor's Manual message 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 C 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 systems 207
Driving and parking Z

the lines on the assistance graphic display are
shown in green ( Y
page 231). Active Lane
Keeping Assist is ready for use. X
To deactivate: press button D .
Indicator lamp C goes out. The Active Lane
Keeping Assist is deactivated. The Lane
Keeping Assist Off message appears in
the multifunction display.
Selecting Standard or Adaptive setting X
In the DriveAssist menu on the on-board
computer, select the Active Lane Keep‐
ing Assist function ( Y
page 233).X
Select setting Standard or Adaptive .
When Standard is selected, no warning vibra-
tion occurs if: R
you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time R
a driving safety system intervenes, such as
ABS, BAS or ESP ®
When Adaptive is selected, no warning vibra-
tion occurs if: R
you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time. R
a driving safety system intervenes, e.g.
ABS, BAS or ESP ®
R
you accelerate hard, e.g. kickdown. R
you brake hard R
you steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly R
you 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: R
you approach the outer lane marking on a
bend R
the road has very wide lanes, e.g. a freeway R
the system detects solid lane markings
The warning vibration occurs later if: R
the road has narrow lanes R
you 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
G WARNING
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" ( Y
page 384).
G WARNING
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.214
Towing a trailer
Driving an d parking

X
Switch off the engine. X
Close the doors and tailgate. X
Couple up the trailer. X
Establish the electrical connection between
the vehicle and the trailer. X
Check that the trailer lighting system is work-
ing. X
Push 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: R
ESP ®
R
PARKTRONIC R
Active Parking Assist R
Active Blind Spot Assist R
Active 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: R
Unless 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: R
Safety 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. R
A separate brake system for certain types of
trailer. R
Safety 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: R
in your place of residence R
at 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: R
Cornering R
Stopping R
Backing up
Check the following before the journey: R
Trailer tow hitch R
Safety switch for braked trailers R
Safety chains R
Electrical connections R
Lighting system R
Wheels and tires R
Load 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: R
is heavier R
is restricted in its acceleration and gradient-
climbing capability R
has an increased braking distance R
is affected more by strong crosswinds R
demands more sensitive steering R
has 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 trailer 217
Driving and parking Z

Display messages
Possible causes/consequences and P Solutions
The yellow $ warning lamp lights up and th e red I (US A only)
or $ (Canada only) indicator lamp flashes .
It is no t possibl e to apply th e electric parking brak e manually.X
Shift th e transmission to position ] .X
Visit a qualified specialist workshop .
' (US A only)
M (Canada only)
Check Brake Fluid
Level There is no t enough brak e flui d in th e brak e fluid reservoir .
In addition , th e ' (US A only) or M (Canada only) warning lamp
lights up in th e instrumen t cluste r and a warning tone sounds.
G WARNIN G
The braking effec t may be impaired.
There is a ris k of an accident.X
Pull ove r and stop th e vehicl e safely as soo n as possible, payin g
attention to roa d and traffic conditions. Do no t continu e drivin g
under any circumstances. X
Secur e th e vehicl e against rollin g away ( Y
page 158).X
Consult a qualified specialist workshop .X
Do no t add brak e fluid . This does no t correc t th e malfunction .
& Check Brake Pad Wea r The brak e pads/linings hav e reached their wear limit.
US A only: th e red ' brak e system warning lamp is lit while th e
engin e is running. X
Visit a qualified specialist workshop .
S Inoperative On e or mor e main features of th e mbrace system are malfunctioning .X
Visit a qualified specialist workshop .
Active Brake Assist
Functions Currently
Limite d See Opera‐
tor's Manual Active Brake Assis t is temporarily inoperative.
Possibl e causes are: R
th e radar sensor system is temporarily inoperative, e.g. due to elec -
tromagneti c radiation emitted by nearby TV or radi o station s or
other source s of electromagneti c radiationR
th e system is outside th e operating temperature rangeR
th e on-boar d voltag e is to o low
Whe n th e causes state d abov e no longer apply, th e display message
disappears.
Active Brake Assis t is operational again .
If th e display message does no t disappear :X
Pull ove r and stop th e vehicl e safely as soo n as possible, payin g
attention to roa d and traffic conditions.X
Secur e th e vehicl e against rollin g away ( Y
page 158).X
Restart th e engine. Display messages 24 5
On-board computer and displays Z

Warning/
indicator
lamp Q Signal type
Possible causes/consequences and P Solutions
I$
Q I (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. X
Observe the additional display messages in the multifunction display.
u
Q The red restraint system warning lamp is lit while the engine is running.
The restraint system is malfunctioning.
G WARNING
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. X
Observe the additional display messages in the multifunction display. X
Drive on carefully. X
Contact a qualified specialist workshop and have the restraint system checked.
For further information about the restraint system, see ( Y
page 44).
Engine Warning/
indicator
lamp Q Signal type
Possible causes/consequences and P Solutions

Depending on the engine, the oil dipstick may be
in a different location.
To check the engine oil level: R
park the vehicle on a level surface R
the engine should be switched off for approx-
imately five minutes if the engine is at normal
operating temperature
Checking the oil level using the oil dip-
stick
Example: checking the engine oil level using
the oil dipstick X
Pull oil dipstick C out of the dipstick guide
tube. X
Wipe off oil dipstick C .X
Slowly slide oil dipstick C into the guide tube
to the stop and take it out again after approx-
imately three seconds.
If the level is between MIN mark

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: R
Use of engine oils and oil filters that have
not been expressly approved for the service
system R
Replacement of engine oil and oil filter after
the replacement interval specified by the
service system has expired R
Use 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) X
Turn cap C counter-clockwise and remove it.X
Add 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. X
Replace cap C on the filler neck and tighten
clockwise.
Ensure that the cap locks into place securely. X
Check the oil level again with the oil dipstick
( Y
page 320).
Further information on engine oil ( Y
page 379).
Additional service products
Important safety notes
G WARNING
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.
G WARNING
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: R
switch off the ignition R
never reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area R
remove jewelry and watches R
keep items of clothing and hair, for exam-
ple, away from moving parts
G WARNING
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.
G WARNING
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.Engine compartment 321
Maintenance and care Z

Checking coolant level
Checking the coolant level (example) X
Park 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. X
Turn the SmartKey to position H in the igni-
tion lock ( Y
page 136).
or X
Press the Start/Stop button twice on vehicles
with KEYLESS-GO or the KEYLESS-GO start
function ( Y
page 137).X
Check the coolant temperature display in the
instrument cluster ( Y
page 37).
The coolant temperature must be below
158 ‡ (70 †). X
Turn the SmartKey to position Z in the igni-
tion lock ( Y
page 136).
or X
Press the Start/Stop button once on vehicles
with KEYLESS-GO or the KEYLESS-GO start
function ( Y
page 137).X
Slowly turn cap C half a turn counter-clock-
wise and allow excess pressure to escape. X
Turn cap C further counter-clockwise and
remove it.
If the coolant is at the level of marker bar

available engine and care oils are suitable for
this.
For heavier soiling, you can apply a fine paint-
work polish with a microfiber cloth. Remove
the excess polish residue after polishing.
Impurities combined with the effects of road grit
and corrosive environmental factors may cause
flash rust to form on the surface. You can
restore the original shine of the exhaust pipe by
cleaning it regularly, especially in winter and
after washing. X
Clean the exhaust pipe with a care product
tested and approved by Mercedes-Benz.
Cleaning the trailer tow hitch
H Environmental note
Dispose of rags soaked in oil and grease in an
environmentally responsible manner.
! Please note the care instructions in the
trailer coupling manufacturer's operating
instructions.
The ball coupling must be cleaned if it becomes
dirty or corroded. X
Remove rust on the ball, e.g. with a wire
brush. X
Remove dirt with a clean, lint-free cloth or a
brush. X
After cleaning, lightly oil or grease the ball
coupling. X
Check that the vehicle's trailer tow hitch is
working properly.
You can also have the maintenance work on the
ball coupling and the trailer tow hitch carried out
by a qualified specialist workshop.
Interior care
Cleaning the display
! For cleaning, do not use any of the following: R
alcohol-based thinner or gasoline R
abrasive cleaning agents R
commercially-available household cleaning
agents
These may damage the display surface. Do
not put pressure on the display surface when cleaning. This could lead to irreparable dam-
age to the display. X
Before cleaning the display, make sure that it
is switched off and has cooled down. X
Clean the display surface using a commer-
cially available microfiber cloth and TFT/LCD
display cleaner. X
Dry the display surface using a dry microfiber
cloth.
Cleaning the plastic trim
G WARNING
Care products and cleaning agents containing
solvents cause surfaces in the cockpit to
become porous. As a result, plastic parts may
come loose in the event of air bag deploy-
ment. There is a risk of injury.
Do not use any care products and cleaning
agents to clean the cockpit.
! Never attach the following to plastic surfa-
ces: R
stickers R
films R
perfume oil container or similar
You could otherwise damage the plastic.
! Do not allow cosmetics, insect repellent or
sunscreen to come into contact with the plas-
tic trim. This maintains the high-quality look of
the surfaces. X
Wipe the plastic trim with a damp, lint-free
cloth, e.g. a microfiber cloth. X
Heavy soiling: use care and cleaning prod-
ucts recommended and approved by
Mercedes-Benz.
The surface may change color temporarily.
Wait until the surface is dry again.
Cleaning the steering wheel and selec-
tor lever X
Thoroughly wipe with a damp cloth or use
leather care agents that have been recom-
mended and approved by Mercedes-Benz. Care 329
Maintenance and care Z