2018 MERCEDES-BENZ GLC check engine light

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

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

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.
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 charge state 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.
Charging the 12 V battery Vehicles with a lithium-ion battery:
! Only use battery chargers with a maximum
charging voltage of 14.4 V.
Al l ve hicles except vehicles with a lithium-
ion battery:
! Only use battery chargers with a maximum
charging voltage of 14.8 V.
G WARNING
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.
G WARNING
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.
G WARNING
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.
All vehicles:
! Only charge the battery using the jump-
starting connection point.
The jump-starting connection point is in the
engine compartment ( Y
page 341).X
Open the hood. X
Connect 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 ( Y
page 341).
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.
All vehicles except vehicles with a lithium-
ion battery: if the warning and indicator lamps
on the instrument cluster do not light up at low
temperatures, it is very likely that the dis-
charged battery has frozen. In this case you may
neither jump-start the vehicle nor charge the
battery. 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 quali-
fied specialist workshop.340
Battery (vehicle)
Breakdown assistance

starting characteristics can be impaired, particularly at low temperatures. Have the thawed battery
checked at a qualified specialist workshop.
All vehicles:
! 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 donor battery using jumper cables.
Observe the following points: R
The battery is not accessible in all vehicles. If the other vehicle's battery is not accessible, jump-
start the vehicle using a donor battery or a jump-starting device. R
you may only jump-start the vehicle when the engine and exhaust system are cold. R
All vehicles except vehicles with a lithium-ion battery: do not start the engine if the battery
is frozen. Let the battery thaw first. R
Jump-starting may be performed only using batteries with a nominal voltage of 12 V. R
Only use jumper cables which have a sufficient cross-section and insulated terminal clamps. R
If 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. R
Make sure that the two vehicles do not touch.
Make sure that: R
The jumper cables are not damaged. R
Bare parts of the terminal clamp do not come into contact with other metal parts while the jumper
cables are connected to the battery. R
The jumper cables cannot come into contact with parts that can move when the engine is running,
such as the V-belt pulley or the fan. X
Secure the vehicle by applying the electric parking brake. X
Shift the transmission to position ] .X
Make 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 Z in the ignition lock and remove it
( Y
page 136).X
Switch off all electrical consumers, e.g. rear window defroster, lighting, etc. X
Open the hood.
i Right-hand-drive vehicle: the jump-starting connection points may be located on the other
side of the vehicle.342
Jump-starting
Breakdown assistance