2018 MERCEDES-BENZ GLS SUV warning

a corresponding warning message will appear in
the multifunction display.
You can recognize the tire pressure loss warning
by theRun 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 361).
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 357).
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.
Ryou are driving on sand or gravel.
Ryou adopt a very sporty driving style (corner-
ing at high speeds or driving with high rates of acceleration).
Ryou are driving with a heavy load (in the vehi-
cle or on the roof).
Restarting the tire pressure loss warn-
ing system
Restart the tire pressure loss warning system ifyou have:
Rchanged the tire pressure
Rchanged the wheels or tires
Rmounted new wheels or tires
XBefore restarting, make sure that the tire
pressures are set properly on all four tires for
the respective operating conditions.
The recommended tire pressure can be found on the Tire and Loading Information placard on the B-pillar. Additionally, a tire pressure
table is attached to the fuel filler flap. The tire
pressure loss warning system can only give
reliable warnings if you have set the correct
tire pressure. If an incorrect tire pressure is
set, these incorrect values will be monitored.
XAlso observe the notes in the section on tire
pressures (Ypage 357).
XMake sure that the SmartKey is in position
2
in the ignition lock (Ypage 140).
XPress the =or; button on the steering
wheel to select the Servicemenu.
XPress the9or: button to select
Tire Pressure.
XPress the abutton.
The Run Flat Indicator Active Press
'OK' to Restartmessage appears in the
multifunction display.
If you wish to confirm the restart:
XPress the abutton.
The Tire Pressure Now OK?message
appears in the multifunction display.
XPress the 9or: button to select Yes.
XPress theabutton.
The Run Flat Indicator Restartedmes-
sage appears in the multifunction display.
After a teach-in period, the tire pressure loss
warning system will monitor the set tire pres-
sures of all four tires.
If you wish to cancel the restart:
XPress the %button.
or
XWhen the TirePressureNowOK?message
appears, press the 9or: button to
select Cancel
.
XPress the abutton.
The tire pressure values stored at the last
restart will continue to be monitored.
Tire pressure monitor
General notes
If a tire pressure monitor is installed, the vehi-
cle's wheels have sensors that monitor the tire
pressures in all four tires. The tire pressure mon-
itor warns you if the pressure drops in one or
more of the tires. The tire pressure monitor only
functions if the corresponding sensors are
installed in all wheels.
Tire pressure361
Wheels and tires
Z

Information on tire pressures is displayed in the
multifunction display. After a few minutes of
driving, the current tire pressure of each tire is
shown in theServ.
menu of the multifunction
display, see illustration (example).
For information on the message display, refer to
the "Checking the tire pressure electronically"
section (
Ypage 363).
Important safety notes
GWARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure rec-
ommended by the vehicle manufacturer on
the Tire and Loading Information placard on
the driver's door B-pillar or the tire pressure
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 Infor-
mation placard or 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 illuminates,
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 stop-
ping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the driv-
er's responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the TPMS low tire pressure telltale.
USA only:
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate if the
system is not operating properly. The TPMS
malfunction indicator is combined with the
low tire pressure telltale. When the system
detects a malfunction, the warning lamp will
flash for approximately a minute and then
remain 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 illuminated,
the system may not be able to detect or signal
low tire pressure as intended. TPMS malfunc-
tions may occur for a variety of reasons,
including the mounting of incompatible
replacement or alternate tires or wheels on
the vehicle that prevent the TPMS from func-
tioning properly. Always check the TPMS mal-
function 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 prop-
erly.
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 357). 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 364). 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 357).
The tire pressure monitor is not able to warn you
of a sudd en loss of pressure, e.g. if the tire is
penetra

ted by a foreign object. In the event of a
362Tire pressure
Wheels and tires

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
too low. The tire pressure monitor is not mal-functioning.
Rif the warning lamp flashes for approximately
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 273).
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 gage. 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 gage 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 140) in the ignition lock.
XPress the =or; button on the steering
wheel to select the Serv.menu.
XPress the9or: button to select
Tire Pressure.
XPress a.
The current tire pressure of each tire is shown
in the multifunction display.
If the vehicle has been parked for longer than
20 minutes, the Tire pressure will be
displayed after driving a few minutesmessage appears.
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, theTire
PressureMonitorActivedisplay message is shown instead of the tire
pressure display. The tire pressures are already
being monitored.
If an emergency spare wheel is mounted, the
system may continue to show the tire pressure
of the wheel that has been removed for a few
minutes. If this occurs, note that the value dis-
played for the position where the spare wheel is
mounted is not the same as the current tire
pressure of the emergency spare wheel.
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 at
least one tire has dropped significantly. The
tires must be checked.
RIf the WarningTireMalfunctionmessage
appears in the multifunction display, the tire
pressure in at least one tire has dropped sud-
denly. The tires must be checked.
Be sure to observe the instructions and safety
notes in the display messages in the "Tires" sec-
tion (
Ypage 273).
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.
Tire pressure363
Wheels and tires
Z

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
the Tire and Loading Information placard on
the driver's side B-pillar (
Ypage 357).
You can find more tire pressure values for
various operating conditions in the tire pres-
sure table inside the fuel filler flap
(
Ypage 358).
XMake sure that the tire pressure is correct on
all four wheels.
XMake sure that the SmartKey is in position 2
in the ignition lock.
XPress the =or; button on the steering
wheel to select the Serv.menu.
XPress the9or: button to select
Tire Pressure.
XPress a.
The multifunction display shows the current
tire pressure for the individual tires or the
Tire pressure will be displayed
after driving a few minutesmessage.
XPress the :button.
The UseCurrentPressuresasNewRef‐erenceValuesmessage appears in the mul-
tifunction display.
If you wish to confirm the restart:
XPress the abutton.
The TirePress.MonitorRestartedmes-
sage appears in the multifunction display.
After driving for a few minutes, the system
checks whether the current tire pressures are
within the specified range. The new tire pres-
sures are then accepted as reference values
and monitored.
If you wish to cancel the restart:
XPress the %button.
The tire pressure values stored at the last
restart will continue to be monitored.
Radio type approval for the tire pres-
sure monitor
CountryRadio type approval number
USAFCC ID: MRXMW2433A
FCC ID: MRXGG4
FCC ID: MRXMC34MA4
CanadaIC: 2546A-MW2433A
IC: 2546A-GG4
IC: 2546A-MC34MA4
Loading the vehicle
Instruction labels for tires and loads
GWARNING
Overloaded tires can overheat, causing a
blowout. Overloaded tires can also impair the steering and driving characteristics and lead
to brake failure. There is a risk of accident.
Observe the load rating of the tires. The load
rating must be at least half of the GAWR of
your vehicle. Never overload the tires by
exceeding the maximum load.
Two instruction labels on your vehicle show the maximum possible load.
(1) The Tire and Loading Information placard is on the B-pillar on the driver's side. The Tire
and Loading Information placard shows the
maximum permissible number of occu-
pants and the maximum permissible vehicle
load. It also contains details of the tire sizes
and corresponding pressures for tires
mounted at the factory.
(2) The vehicle identification plate is on the B- pillar on the driver's side. The vehicle iden-
tification plate informs you of the gross
vehicle weight rating. It is made up of the
vehicle weight, all vehicle occupants, the
fuel and the cargo. You can also find infor-
mation about the maximum gross axle
weight rating on the front and rear axle.
The maximum gross axle weight rating is
the maximum weight that can be carried by
one axle (front or rear axle). Never exceed
the maximum load or the maxi mum g
ross
axle weight rating for the front or rear axle.
364Loading the vehicle
Wheels and tires

All passenger car tires must conform to the stat-
utory safety requirements in addition to these
grades.
iThe actual values for tires are vehicle-spe-
cific and may deviate from the values in the
illustration.
Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified U.S.
government course. For example, a tire graded
150 would wear one and one-half times as well
on the government course as a tire graded 100.
The relative performance of tires depends upon
the actual conditions of their use, however, and
may depart significantly from the norm due to
variations in driving habits, service practices
and differences in road characteristics and cli-
mate.
Traction
GWARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration, cor-
nering, hydroplaning, or peak traction char-
acteristics.
!Avoid wheelspin. This can lead to damage to
the drive train.
The traction grades – from highest to lowest –
are AA, A, B and C. Those grades represent the
tire's ability to stop on wet pavement as meas-
ured under controlled conditions on specified
government test surfaces of asphalt and con-
crete. A tire marked C may have poor traction
performance.
The safe speed on a wet, snow covered or icy
road is always lower than on dry road surfaces.
You should pay special attention to road condi-
tions when temperatures are around freezing
point.
Mercedes-Benz recommends a minimum tread
depth of ãin (4 mm) on all four winter tires.
Observe the legally required minimum tire tread
depth (
Ypage 355). Winter tires can reduce the
braking distance on snow-covered surfaces in
comparison with summer tires. The braking dis-
tance is still much further than on surfaces that are not icy or covered with snow. Take appro-
priate care when driving.
Further information on winter tires (M+S
tires)
(
Ypage 356).
Temperature
GWARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla-
tion, or excessive loading, either separately or
in combination, can cause excessive heat
build-up and possible tire failure.
The temperature grades are A (the highest), B,
and C, representing the tire's resistance to the
generation of heat and its ability to dissipate
heat when tested under controlled conditions
on a specified indoor laboratory test wheel. Sus-
tained high temperature can cause the material
of the tire to degenerate and reduce tire life, and
excessive temperature can lead to sudden tire
failure. The grade C corresponds to a level of
performance which all passenger car tires must
meet under the Federal Motor Vehicle Safety
Standard No. 109. Grades B and A represent
higher levels of performance on the laboratory
test wheel than the minimum required by law.
368All about wheels and tires
Wheels and tires

Tire labeling
Overview
:Uniform Tire Quality Grading Standards
(Ypage 372)
;Department of Transportation, Tire Identifi-
cation Number (Ypage 371)
=Maximum load rating (Ypage 371)
?Maximum tire pressures (Ypage 360)
AManufacturer
BTire material (Ypage 372)
CTire size designation, load-bearing capacity
and speed rating (Ypage 369)
DLoad index (Ypage 371)
ETire name
The markings described above are on the tire in
addition to the tire name (sales designation) and
the manufacturer's name.
iTire data is vehicle-specific and may deviate
from the data in the example.
Tire size designation, load-bearing
capacity and speed rating
GWARNING
Exceeding the stated tire load-bearing capa-
city and the approved maximum speed could
lead to tire damage or the tire bursting. There is a risk of accident.
Therefore, only use tire types and sizes
approved for your vehicle model. Observe the
tire load rating and speed rating required for
your vehicle.
:Tire width
;Nominal aspect ratio in %
=Tire code
?Rim diameter
ALoad bearing index
BSpeed rating
General: depending on the manufacturer's
standards, the size imprinted in the tire wall may
not contain any letters or may contain one letter
that precedes the size description.
If there is no letter preceding the size descrip-
tion (as shown above): these are passenger
vehicle tires according to European manufac-
turing standards.
If "P" precedes the size description: these are
passenger vehicle tires according to U.S. man-
ufacturing standards.
If "LT" precedes the size description: these are
light truck tires according to U.S. manufacturing
standards.
If "T" precedes the size description: compact
emergency wheels with high tire pressure that
are only designed for temporary use in an emer-
gency.
Tire width: tire width:shows the nominal tire
width in millimeters.
Height-width ratio: aspect ratio;is the size
ratio between the tire height and tire width and
is shown in percent. The aspect ratio is calcula-
ted by dividing the tire width by the tire height.
Tire code: tire code=specifies the tire type.
"R" represents radial tires; "D" represents diag-
onal tires
; "B" represents diagonal radial tires.
Optionally, tires with a maximum speed of over
149 mph (240 km/h) may have "ZR" in the size
All about wheels an d tires369
Wheels and tires
Z

Sidewall
The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
parts and more than 2.3 kg (5 lbs). These
optional extras, such as high-performance
brakes, level control, a roof rack or a high-per-
formance battery, are not included in the curb
weight and the weight of the accessories.
TIN (Tire Identification Number)
This is a unique identifier which can be used by
a tire manufacturer to identify tires, for example
for a product recall, and thus identify the pur-
chasers. The TIN is made up of the manufactur-
er's identity code, tire size, tire type code and
the manufacturing date.
Load bearing index
The load bearing index (also load index) is a code
that contains the maximum load bearing capa-
city of a tire.
Traction
Traction is the result of friction between the tires
and the road surface.
TWR (Tongue Weight Rating)
The TWR specifies the maximum permissible
weight that the ball coupling of the trailer tow
hitch can support.
Treadwear indicators
Narrow bars (tread wear bars) that are distrib-
uted over the tire tread. If the tire tread is level
with the bars, the wear limit ofáin (1.6 mm)
has been reached.
Occupant distribution
The distribution of occupants in a vehicle at their
designated seating positions.
Total load limit
Nominal load and luggage load plus 68 kg
(150 lbs) multiplied by the number of seats in
the vehicle.
Changing a wheel
Flat tire
The "Breakdown assistance" section
(Ypage 339) contains information and notes on
how to deal with a flat tire. Information on driv-
ing with MOExtended tires in the event of a flat
tire can be found under "MOExtended tires (tires
with run-flat characteristics" (
Ypage 340).
Vehicles with an emergency spare wheel: in
the event of a flat tire, mount the emergency
spare wheel according to the description under "Mounting a wheel" (
Ypage 375).
Rotating the wheels
GWARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics if
the wheels or tires have different dimensions. The wheel brakes or suspension components
may also be damaged. There is a risk of acci-
dent.
Rotate front and rear wheels only if the wheels and tires are of the same dimensions.
!On vehicles equipped with a tire pressure
monitor, electronic components are located
in the wheel.
Tire-mounting tools should not be used near
the valve. This could damage the electronic
components.
Only have tires changed at a qualified spe-
cialist workshop.
Always observe the instructions and safety
notes in the "Mounting a wheel" section
(
Ypage 375).
The wear patterns on the front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before a clear wear pattern
has formed on the tires. Front tires typically
wear more on the shoulders and the rear tires in
the center.
On vehicles that have the same size front and
rear wheels, you can rotate the wheels accord-
ing to the intervals in the tire manufacturer's
warranty book in your vehicle documents. If no
warranty book is available, the tires should be
rotated every 3,000 to 6,000 miles (5,000 to
10,000 km). Depending on tire wear, this may
374Changing a wheel
Wheels and tires

be required earlier. Do not change the direction
of wheel rotation.
Clean the contact surfaces of the wheel and the
brake disc thoroughly every time a wheel is rota-ted. Check the tire pressure and, if necessary,
restart the tire pressure loss warning system or
the tire pressure monitor (
Ypage 361).
Direction of rotation
Tires with a specified direction of rotation have
additional benefits, e.g. if there is a risk of hydro-
planing. These advantages can only be gained if
the tires are installed corresponding to the
direction of rotation.
An arrow on the sidewall of the tire indicates its
correct direction of rotation.
Storing wheels
Store wheels that are not being used in a cool,
dry and preferably dark place. Protect the tires
from oil, grease, gasoline and diesel.
Mounting a wheel
Preparing the vehicle
XVehicle with emergency spare wheel:
when mounting the emergency spare wheel in
the event of a flat tire, follow the additional
notes on vehicle preparation under "Flat tire"
(
Ypage 339).
XStop the vehicle on solid, non-slippery and
level ground.
XApply the electric parking brake manually.
XBring the front wheels into the straight-ahead
position.
XVehicles with automatic transmission:
shift the transmission to position j.
XVehicles with the AIRMATIC package:
make sure that the normal vehicle level is
selected (
Ypage 190).
XVehicles with the Off-Road Engineering
package:make sure that the normal level is
selected (
Ypage 184).
XSwitch off the engine.
XVehicles without KEYLESS-GO: remove the
SmartKey from the ignition lock.
XVehicles with KEYLESS-GO: open the driv-
er's door.
The vehicle electronics are now in position
u. This means no SmartKey is in the ignition
lock.
XVehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock
(
Ypage 140).
XIf included in the vehicle equipment, remove
the tire-change tool kit from the vehicle.
XSafeguard the vehicle against rolling away.
iApart from certain country-specific varia-
tions, vehicles are not equipped with a tire-
change tool kit. For more information on
which tools are required to perform a wheel
change on your vehicle, consult a qualified
specialist workshop.
Necessary tire-changing tools can include, for
example:
RJack
RWheel chock
RLug wrench
Securing the vehicle to prevent it from
rolling away
If your vehicle is equipped with a wheel chock, it can be found in the tire-change tool kit
(
Ypage 339).
The folding wheel chock is an additional safety
measure to prevent the vehicle from rolling
away, for example when changing a wheel.
XFold both plates upwards :.
XFold out lower plate;.
XGuide the lugs on the lower plate fully into the
openings in base plate =.
Changing a wheel375
Wheels and tires
Z