2018 MERCEDES-BENZ GLC COUPE Owner's Manual

MOExtended tires (tires with run-flat
properties)
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.
MOExtended tires may only be used in conjunc-
tion with an active tire pressure loss warning
system or with an active tire pressure monitor
and on wheels specifically tested by Mercedes-
Benz.
Notes on driving with MOExtended tires with a
flat tire (
Ypage 318).
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 can be obtained from a qualified specialist workshop.
Winter operation
General notes
Have your vehicle winter-proofed at a qualified
specialist workshop at the onset of winter.
Observe the notes in the "Changing a wheel"
section (
Ypage 353).
Driving with summer tires
At temperatures below 45 ‡ (+7 †), summer
tires lose elasticity and therefore traction and
braking power. Change the tires on your vehicle
to M+S tires. Using summer tires at very cold
temperatures could cause cracks to form,
thereby damaging the tires permanently.
Mercedes-Benz cannot accept responsibility for
this type of damage.
GWARNING
Damaged tires can cause tire inflation pres-
sure loss. As a result, you could lose control of
your vehicle. There is a risk of accident.
Check the tires regularly for signs of damage
and replace any damaged tires immediately.
M+S tires
GWARNING
M+S tires with a tire tread depth of less than
ã in (4 mm) are not suitable for use in winter
and do not provide sufficient traction. There is
a risk of an accident.
M+S tires with a tread depth of less than ãin
(4 mm) must be replaced immediately.
At temperatures below 45 ‡(+7 †), use winter
tires or all-season tires. Both types of tire are
identified by the M+S marking.
Only winter tires bearing the isnowflake
symbol in addition to the M+S marking provide
the best possible grip in wintry road conditions.
Only these tires will allow driving safety systems
such as ABS and ESP
®to function optimally in
winter. These tires have been developed specif-
ically for driving in snow.
Use M+S tires of the same make and tread on all
wheels to maintain safe handling characteris-
tics.
Always observe the maximum permissible
speed specified for the M+S tires you have
mounted.
When you have mounted the M+S tires:
XCheck the tire pressures (Ypage 339).
XVehicles for Canada: restart the tire pres-
sure loss warning system (Ypage 340).
XRestart the tire pressure monitor
(Ypage 342).
Snow chains
GWARNING
If snow chains are installed to the front
wheels, they may drag against the vehicle
body or chassis components. This could
cause damage to the vehicle or the tires.
There is a risk of an accident.
To avoid hazardous situations:
Rnever install snow chains to the front
wheels
Ralways install snow chains in pairs to the
rear wheels.
Winter operation335
Wheels and tires
Z

For safety reasons, Mercedes-Benz recom-
mends that you only use snow chains that have
been specially approved for your vehicle by
Mercedes-Benz, or are of a corresponding
standard of quality. For more information,
please contact a qualified specialist workshop.
If you intend to mount snow chains, please bear
the following points in mind:
RSnow chains may not be mounted on all
wheel/tire combinations. Observe the infor-
mation regarding permitted wheel/tire com-
binations (
Ypage 357).
ROnly use snow chains when driving on roads
completely covered by snow. Remove the
snow chains as soon as possible when you
come to a road that is not snow-covered.
RLocal regulations may restrict the use of snowchains. Observe the appropriate regulations if
you wish to mount snow chains.
RDo not exceed the maximum permissible
speed of 31 mph (50 km/h).
ROn vehicles with AIR BODY CONTROL, you
must only drive at raised vehicle level if snow chains have been installed (
Ypage 170).
RYou must never use Parking Pilot (Ypage 174)
when snow chains are installed.
You may wish to deactivate ESP
®when pulling
away with snow chains installed:
RAll vehicles (except Mercedes ‑AMG vehicles)
(Ypage 69)
RMercedes ‑AMG vehicles (Ypage 70)
You can thereby allow the wheels to spin in a
controlled manner, achieving an increased driv- ing force (cutting action).
Tire pressure
Tire pressure specifications
Important safety notes
GWARNING
Underinflated or overinflated tires pose the
following risks:
Rthe tires may burst, especially as the load
and vehicle speed increase.
Rthe tires may wear excessively and/or
unevenly, which may greatly impair tire
traction.
Rthe driving characteristics, as well as steer-
ing and braking, may be greatly impaired.
There is a risk of an accident.
Follow recommended tire inflation pressures
and check the pressure of all the tires includ-
ing the spare wheel:
Rmonthly, at least
Rif the load changes
Rbefore beginning a long journey
Runder different operating conditions, e.g.
off-road driving
If necessary, correct the tire pressure.
The data on the Tire and Loading Information
placard and tire pressure table shown here are
examples. Tire pressure specifications are vehi-
cle-specific and may deviate from the data
shown here. The tire pressure specifications
that are valid for your vehicle can be found on
the Tire and Loading Information placard and
tire pressure table on the vehicle.
General notes
The recommended tire pressures for the tires
mounted at the factory can be found on the
labels described here.
Operation with a trailer: the applicable value
for the rear axle is the maximum tire pressure
value stated in the table inside the fuel filler flap.
Further information on tire pressures can be
obtained at a qualified specialist workshop.
336Tire pressure
Wheels and tires

Tire and Loading Information placard
:Recommended tire pressures
The Tire and Loading Information placard is on
the B-pillar on the driver's side (
Ypage 343).
The Tire and Loading Information placard con-
tains the recommended tire pressures for cold
tires. The recommended tire pressures are valid
for the maximum permissible load and up to the
maximum permissible vehicle speed.
Tire pressure table
The tire pressure table is on the inside of the fuel
filler flap. It shows the tire pressure for all tires
permitted at the factory for this vehicle; see
illustration (example).
The tire pressure table contains the recommen-
ded pressures for cold tires for various operat-
ing conditions, i.e. differing load and speed con-
ditions.
If a tire size precedes a tire pressure, the tire
pressure information following is only valid for
that tire size. If a speed range precedes the tire pressure, the following tire pressure data
applies to only this speed range.
The load conditions "partially laden" and "fully
laden" are defined in the table for different num- bers of occupants and amounts of luggage. The
actual number of seats may differ.
Some tire pressure tables show only the rim
diameters instead of the full tire size, e.g.
R18.
Rim diameter is part of the tire size and can be
found on the tire sidewall (
Ypage 348).
If the tire pressures have been set to the lower
values for lighter loads and/or lower road
speeds, the pressures should be reset to the
higher values:
Rif you want to drive with an increased load
and/or
Rif you want to drive at higher road speeds
The tire pressures for increased loads and/or
higher road speeds, shown in the tire pressure
table, may have a negative effect on driving
comfort.
If the tire pressure is not set correctly, this can
lead to an excessive build up of heat and a sud-
den loss of pressure.
For more information, contact a qualified spe-
cialist workshop.
Important notes on tire pressure
GWARNING
If the tire pressure drops repeatedly, the
wheel, valve or tire may be damaged. Tire
pressure that is too low may result in a tire
blow-out. There is a risk of an accident.
RCheck the tire for foreign objects.
RCheck whether the wheel is losing air or the valve is leaking.
If you are unable to rectify the damage, con-
tact a qualified specialist workshop.
Tire pressure337
Wheels and tires
Z

GWARNING
If you fit unsuitable accessories onto tire
valves, the tire valves may be overloaded and
malfunction, which can cause tire pressure
loss. Due to their design, retrofitted tire pres- sure monitors keep the tire valve open. This
can also result in tire pressure loss. There is a
risk of an accident.
Only screw the standard valve cap or other
valve caps approved by Mercedes-Benz for
your vehicle onto the tire valve.
Use a suitable pressure gauge to check the tire
pressure. The outer appearance of a tire does
not permit any reliable conclusion about the tire pressure. On vehicles equipped with the elec-
tronic tire pressure monitor, the tire pressure
can be checked in the on-board computer.
The tire temperature and pressure increase
when the vehicle is in motion. This is dependent
on the driving speed and the load.
Therefore, you should only correct tire pres-
sures when the tires are cold.
The tires are cold:
Rif the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and
Rif the vehicle has not been driven further than
1 mile (1.6 km)
The tire temperature changes depending on the
outside temperature, the vehicle speed and the
tire load. If the tire temperature changes by
18 ‡ (10 †), the tire pressure changes by
approximately 10 kPa (0.1 bar/1.5 psi). Take
this into account when checking the pressure of
warm tires. Only correct the tire pressure if it is
too low for the current operating conditions. If
you check the tire pressure when the tires are
warm, the resulting value will be higher than if
the tires were cold. This is normal. Do not
reduce the tire pressure to the value specified
for cold tires. The tire pressure would otherwise
be too low.
Observe the recommended tire pressures for
cold tires:
Ron the Tire and Loading Information placard
on the B-pillar on the driver's side
Rin the tire pressure table on the fuel filler flap
(Ypage 336)
Underinflated or overinflated tires
Underinflated tires
GWARNING
Tires with pressure that is too low can over-
heat and burst as a consequence. In addition, they also suffer from excessive and/or irreg-
ular wear, which can severely impair the brak-
ing properties and the driving characteristics.
There is a risk of an accident.
Avoid tire pressures that are too low in all the
tires, including the spare wheel.
Underinflated tires may:
Roverheat, leading to tire defects
Radversely affect handling
Rwear excessively and/or unevenly
Rhave an adverse effect on fuel consumption
Overinflated tires
GWARNING
Tires with excessively high pressure can burst
because they are damaged more easily by
road debris, potholes etc. In addition, they
also suffer from irregular wear, which can
severely impair the braking properties and the driving characteristics. There is a risk of an
accident.
Avoid tire pressures that are too high in all the
tires, including the spare wheel.
Overinflated tires may:
Rincrease the braking distance
Radversely affect handling
Rwear excessively and/or unevenly
Rhave an adverse effect on ride comfort
Rbe more susceptible to damage
338Tire pressure
Wheels and tires

Maximum tire pressures
:Example: maximum permissible tire pres-
sure
Never exceed the maximum permissible tire
inflation pressure. Always observe the recom-
mended tire pressure for your vehicle when
adjusting the tire pressure (
Ypage 336).
iThe actual values for tires are vehicle-spe-
cific and may deviate from the values in the
illustration.
Checking the tire pressures
Important safety notes
Observe the notes on tire pressure
(Ypage 336).
Information on air pressure for the tires on your
vehicle can be found:
Ron the vehicle's Tire and Loading Information
placard on the B-pillar
Rin the tire pressure table in the fuel filler flap
(Ypage 336)
Rin the "Tire pressure" section
Checking tire pressures manually
To determine and set the correct tire pressure,
proceed as follows:
XRemove the valve cap of the tire that is to be
checked.
XPress the tire pressure gauge securely onto
the valve.
XRead the tire pressure and compare it to the
recommended value on the Tire and Loading
Information placard or the tire pressure table (
Ypage 336).
XIf the tire pressure is too low, increase the tire
pressure to the recommended value.
XIf the tire pressure is too high, release air. To
do so, press down the metal pin in the valve,
using the tip of a pen for example. Then check
the tire pressure again using the tire pressure
checker.
XScrew the valve cap onto the valve.
XRepeat these steps for the other tires.
Tire pressure loss warning system
General notes
While the vehicle is in motion, the tire pressure
loss warning system monitors the set tire pres-
sure using the rotational speed of the wheels.
This enables the system to detect significant
pressure loss in a tire. If the speed of rotation of
a wheel changes as a result of a loss of pressure,
a corresponding warning message will appear in
the multifunction display.
You can recognize the tire pressure loss warning
by the Run Flat Indicator Active
Press'OK' to Restartmessage which appears in
the Servicemenu of the multifunction display.
Information on the message display can be
found in the "Restarting the tire pressure loss
warning system" section (
Ypage 340).
Important safety notes
The tire pressure warning system does not warn you of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(
Ypage 336).
The tire pressure loss warning does not replace
the need to regularly check the tire pressure. An
even loss of pressure on several tires at the
same time cannot be detected by the tire pres-
sure loss warning system.
The tire pressure monitor is not able to warn you
of a sudden loss of pressure, e.g. if the tire is
penetrated by a foreign object. In the event of a
sudden loss of pressure, bring the vehicle to a
halt by braking carefully. Avoid abrupt steering
movements.
The function of the tire pressure loss warning
system is limited or delayed if:
Rsnow chains are mounted on your vehicle's
tires.
Rroad conditions are wintry.
Tire pressure339
Wheels and tires
Z

Ryou are drivingon san dor gravel .
Ryou adop t averysport ydrivin gstyle (corner-
in gat high speeds or drivin gwit hhigh rates of
acceleration).
Ryou are towin g averyheav yor larg etrailer .
Ryou are drivin gwit h a heav yload (in th evehi-
cle or on th eroof).
Resta rting the ti repressure loss warn-
ing system
Restart th etire pressur eloss warnin gsystem if
you have:
Rchanged th etire pressur e
Rchanged thewheels or tires
Rmounte dne wwheels or tires
XBefor erestarting ,mak esur ethat th etire
pressures are set properly on all fou rtires for
th erespective operating conditions.
The recommended tire pressur ecan be found
on th eTir eand Loadin gInformation placard
on th eB-pillar .Additionally, atire pressur e
table is attached to th efuel filler flap .The tire
pressur eloss warnin gsystem can only giv e
reliable warnings if you hav eset th ecorrec t
tire pressure. If an incorrec ttire pressur eis
set ,these incorrec tvalue swill be monitored.
XAlso observ eth enote sin th esection on tire
pressures (Ypage 336).
XMakesur ethat th eSmartKey is in position 2
in th eignition loc k (Ypage 130).
XPressòon thesteerin gwhee lto cal lup
th emen ulist .
XPress 9or: on thesteerin gwhee lto
select th eServic emenu.
XConfirmby pressing aon thesteerin g
wheel.
XPress 9or: to select TirePres‐sur e.
XPress ato confirm .
The Run Fla tIndicator ActivePress'OK 'to Restar tmessage is shown in th e
multifunction display. If you wish to confir
mtherestart :
XPress th ea button.
The TirePressure Now OK?message is
shown on th emultifunction display.
XPress 9or: to select Yes.
XPressato confirm .
The Run Fla tIndicator Restartedmes -
sage is shown on th emultifunction display.
Afte r ateach-i nperiod, th etire pressur eloss
warnin gsystem will monitor th eset tire pres-
sures of all fou rtires .
If you wish to cancel th erestart :
XPress th e% button.
or
XIf th eTir ePressure Now OK?message
appears ,press 9or: to select Can‐
cel.
XPress ato confirm .
The tire pressur evalue sstore dat th elast
restar twill continue to be monitored.
Ti re pressure mo nitor
Gene ral notes
Ifatire pressur emonitor is installed ,th evehi-
cle's wheels hav esensor sthat monitor th etire
pressures in all fou rtires .The tire pressur emon -
itor warn syou if th epressur edrops in on eor
mor eof th etires .The tire pressur emonitor only
function sif th ecorrespondin gsensor sare
installed in all wheels.
Information on tire pressures is displayed in th e
multifunction display. Afte r afew minute sof
driving, th ecurren ttire pressur eof eac htire is
shown in th eServic e
menuof th emultifunction
display; see illustration (example).
340Tire pressure
Wheels and tires

Information on the message display can be
found in the "Checking the tire pressure elec-
tronically" section (
Ypage 342).
Important safety notes
GWARNING
Each tire, including the spare (if provided),
should be checked at least once every two
weeks when cold and inflated to the pressure recommended by the vehicle manufacturer
on the Tire and Loading Information placard
on the driver's door B-pillar or the tire pres-
sure label on the inside of the fuel filler flap. If
your vehicle has tires of a different size than
the size indicated on the Tire and Loading
Information placard or, if available, the tire
pressure label, you should determine the
proper tire pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring
system (TPMS) that illuminates a low tire pres-
sure telltale when one or more of your tires
are significantly underinflated. Accordingly,
when the low tire pressure telltale lights up,
you should stop and check your tires as soon
as possible, and inflate them to the proper
pressure. Driving on a significantly underin-
flated tire causes the tire to overheat and can
lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle's
handling and stopping ability. Please note thatthe TPMS is not a substitute for proper tire
maintenance, and it is the driver's responsi-
bility to maintain correct tire pressure, even if
underinflation has not reached the level to
trigger illumination of the TPMS low tire pres-
sure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined with
the low tire pressure telltale. When the sys-
tem detects a malfunction, the warning lamp
will flash for approximately a minute and thenremain continuously illuminated. This
sequence will be repeated every time the vehi-
cle is started as long as the malfunction
exists. When the malfunction indicator is illu-
minated, the system may not be able to detect
or signal low tire pressure as intended.
TPMS malfunctions may occur for a variety of
reasons, including the installation of incom-
patible replacement or alternate tires or
wheels on the vehicle that prevent the TPMS
from functioning properly. Always check the
TPMS malfunction telltale after replacing one
or more tires or wheels on your vehicle to
ensure that the replacement or alternate Tires
and wheels allow the TPMS to continue to
function properly.
It is the driver's responsibility to set the tire
pressure to that recommended for cold tires
which is suitable for the operating situation
(
Ypage 336). Note that the correct tire pressure
for the current operating situation must first be
taught-in to the tire pressure monitor. If a sub-
stantial loss of pressure occurs, the warning
threshold for the warning message is aligned to
the taught-in reference values. Restart the tire
pressure monitor after adjusting the pressure of
the cold tires (
Ypage 342). The current pres-
sures are saved as new reference values. As a
result, a warning message will appear if the tire pressure drops significantly.
The tire pressure monitor does not warn you of
an incorrectly set tire pressure. Observe the
notes on the recommended tire pressure
(
Ypage 336).
The tire pressure monitor is not able to warn you
of a sudden loss of pressure, e.g. if the tire is
penetrated by a foreign object. In the event of a
sudden loss of pressure, bring the vehicle to a
halt by braking carefully. Avoid abrupt steering
movements.
The tire pressure monitor has a yellow warning
lamp in the instrument cluster for indicating
pressure loss or a malfunction. Whether the
warning lamp flashes or lights up indicates
whether a tire pressure is too low or the tire
pressure monitor is malfunctioning:
Rif the warning lamp is lit continuously, the tire
pressure on one or more tires is significantly
Tire pressure341
Wheels and tires
Z

too low. The tire pressure monitor is not mal-
functioning.
Rif the warning lamp flashes for around a
minute and then remains lit constantly, the
tire pressure monitor is malfunctioning.
In addition to the warning lamp, a message
appears in the multifunction display. Observe
the information on display messages
(
Ypage 248).
It may take up to ten minutes for a malfunction
of the tire pressure monitor to be indicated. A
malfunction will be indicated by the tire pres-
sure warning lamp flashing for approximately
one minute and then remaining lit. When the
malfunction has been rectified, the tire pressure
warning lamp goes out after a few minutes of
driving.
The tire pressure values indicated by the on-
board computer may differ from those meas-
ured at a gas station with a pressure gauge. The
tire pressures shown by the on-board computer
refer to those measured at sea level. At high
altitudes, the tire pressure values indicated by a
pressure gauge are higher than those shown by
the on-board computer. In this case, do not
reduce the tire pressures.
The operation of the tire pressure monitor can
be affected by interference from radio transmit-
ting equipment (e.g
. radio headphones, two-way
radios) that may be being operated in or near the
vehicle.
Checking the tire pressure electroni-
cally
XMake sure that the SmartKey is in position 2
(Ypage 130) in the ignition lock.
XPress òon the steering wheel to call up
the menu list.
XPress 9or: on the steering wheel to
select the Servicemenu.
XConfirm by pressing aon the steering
wheel.
XPress 9or: to select Tire Pres‐sure.
XPressato confirm.
The multifunction display shows the current
tire pressure of each wheel.
If the vehicle was parked for longer than
20 minutes, the following message appears:
Tire
pressurewillbedisplayedafterdriving a few minutes. After a teach-in process, the tire pressure mon-
itor automatically detects new wheels or new
sensors. As long as a clear allocation of the tire
pressure value to the individual wheels is not
possible, the
Tire
PressureMonitorActivemessage is shown instead of the tire pressure
display. The tire pressures are already being
monitored.
Tire pressure monitor warning mes-
sages
If the tire pressure monitor detects a pressure
loss in one or more tires, a warning message is
shown in the multifunction display. The yellow
tire pressure warning lamp then lights up.
RIf thePlease Correct Tire Pressuremessage appears in the multifunction display,
the tire pressure in at least one tire is too low.
The tire pressure must be corrected when the
opportunity arises.
RIf theCheck Tiresmessage appears in the
multifunction display, the tire pressure in one
or more tires has dropped significantly. The
tires must be checked.
RIf the WarningTireMalfunctionmessage
appears in the multifunction display, the tire
pressure in one or more tires has dropped
suddenly. The tires must be checked.
Be sure to observe the instructions and safety
notes in the display messages in the "Tires" sec- tion (
Ypage 248).
If the wheel positions on the vehicle are rotated,
the tire pressures may be displayed for the
wrong positions for a short time. This is rectified after a few minutes of driving, and the tire pres-
sures are displayed for the correct positions.
Restarting the tire pressure monitor
When you restart the tire pressure monitor, all
existing warning messages are deleted and the
warning lamps go out. The monitor uses the cur-
rently set tire pressures as the reference values
for monitoring. In most cases, the tire pressure
monitor will automatically detect the new refer-
ence values after you have changed the tire
pressure. However, you can also set reference
values manually as described here. The tire
pressure monitor then monitors the new tire
pressure values.
XSet the tire pressure to the value recommen-
ded for the corresponding driving situation on
342Tire pressure
Wheels and tires