light MERCEDES-BENZ G-CLASS SUV 2015 Owners Manual

Please note that the TPMS is not a substitutefor 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 the recommended cold tire pres-
sure suitable for the operating situation( Y page 232). Note that the correct tire pres-
sure for the current operating situation must
first be taught-in to the tire pressure monitor. If there is a substantial loss of pressure, the
warning threshold for the warning message isaligned to the reference values taught-in.
Restart the tire pressure monitor after adjust-
ing to the cold tire pressure ( Ypage 238).
The current pressures are saved as new ref-
erence values. As a result, a warning message
will appear if the tire pressure drops signifi-
cantly. The tire pressure monitor does not warn you
of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
( Y page 232).
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
sudden steering movements.
In order to check the tire pressure, the vehi-
cle's wheels are installed with sensors that
monitor the tire pressure in all four tires. The
tire pressure monitor warns you if the pres-
sure drops in one or more of the tires. The tire pressure monitor only functions if the correct
sensors are installed on all wheels.
The tire pressure monitor has a yellow warn-
ing lamp in the instrument cluster for indicat- ing pressure loss/malfunctions (USA) or
pressure loss (Canada). Whether the warning
lamp flashes or lights up indicates whether a
tire pressure is too low or the tire pressure
monitor is malfunctioning:
R if the warning lamp is lit continuously, the
tire pressure on one or more tires is signif-
icantly too low. The tire pressure monitor is not malfunctioning.
R USA only: if the warning lamp flashes for
around a minute and then remains lit con-
stantly, the tire pressure monitor is mal-
functioning.
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 the multifunction display.
USA only: the tire pressure warning lamp will
inform you of a malfunction in the tire pres-
sure monitor by flashing for approximately
one minute and then remaining lit. It may take
more than ten minutes before the data menu
is displayed. 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-
236Tire pressure
Wheels and tires

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 val-
ues 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 trans-
mitting equipment (e.g. radio headphones,
two-way radios) that may be being operated
in or near the vehicle.
iUSA only:
This device complies with part 15 of the
FCC Rules. Operation is subject to the fol-
lowing two conditions:
1. This device may not cause harmful inter- ference, and
2. This device must accept any interference
received, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
iCanada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause harmful inter- ference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
Checking the tire pressure electroni-cally
X Make sure that the SmartKey is in posi-
tion 2in the ignition lock ( Ypage 103).
X Press the =or; button on the steer-
ing wheel to select the
Serv.menu. X
Press the 9or: button to select
Tire Pressure.
X Press the abutton.
The current tire pressure of each tire is
shown in the multifunction display.
If the vehicle has been parked for over
20 minutes, the
Tire pressure will be
displayed after driving a few
minutesmessage appears.
After a teach-in process, the tire pressure
monitor 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 Pressure
Monitor Activedisplay message is shown
instead of the tire pressure display. The tire
pressures are already being monitored.
iIf a spare wheel is mounted, the system
may continue to show the tire pressure of
the wheel that has been removed for a few minutes. Observe that the displayed value
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 signifi-
cant pressure loss on one or more tires, a
warning message is shown in the multifunc-
tion display. A warning tone also sounds and
the tire pressure warning lamp lights up in the
instrument cluster.
Each tire that is affected by a significant loss of pressure is highlighted in the pressure dis-
play.
X If the
Correct Tire Pressuremessage
appears in the multifunction display, check the tire pressure on all four wheels and cor-
rect it if necessary.
X If the
CheckTiresmessage appears in the
multifunction display, the tire pressure in
one or more tires has dropped significantly and the tires must be checked.
X If the
Tire Press. Warning Caution
Tire Malfunctionmessage appears in
Tire pressure237
Wheels and ti res
Z

which all passenger car tires must meet underthe 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.
Tire labeling
Overview of tire labeling
:Uniform tire Quality Grading Standard ( Y page 248)
;DOT tire Identification Number(Y page 247)
=Maximum tire load ( Ypage 246)
?Maximum tire pressures ( Ypage 235)
AManufacturer
BTire material ( Ypage 247)
CTire size designation, load-bearing capa-
city and speed rating ( Ypage 244)
DLoad identification ( Ypage 246)
ETire name
The markings described above are on the tire in addition to the tire name (sales designa-
tion) and the manufacturer's name.
iTire data is vehicle-specific and may devi-
ate 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
;Height-width ratio in percentage
=Tire code
?Rim diameter
ALoad bearing index
BSpeed rating
General: depending on the manufacturer's
standards, a letter is imprinted into the tire
wall before 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:
passenger vehicle tires according to U.S.
manufacturing standards.
If "P" precedes the size description: light
truck tires according to U.S. manufacturing
standards.
If "T" precedes the size description: these are
compact emergency spare wheels at high tire
244Tire labeling
Wheels and tires

the maximum speed of the tire is limited to
186 mph (300 km/h ).
R The size description for all tires with maxi-
mum speeds of over 186 mph (300 km/ h)
must include "ZR", andthe service specifi-
cation must be given in parentheses. Exam- ple: 275/40 ZR 18 (99 Y). Speed rating
"(Y)" indicates that the maximum speed of
the tire is over 186 mph (300 km/h). Ask
the tire manufacturer about the maximum
speed.
All-weather tires and winter tires
IndexSpeed rating
Q M+S 4up to 100 mph (160 km/h)
T M+S
4up to 118 mph (190 km/h)
H M+S 4up to 130 mph (210 km/h)
V M+S4up to 149 mph (240 km/h)
iNot all tires with the M+S marking provide
the driving characteristics of winter tires. In
addition to the M+S marking, winter tires
also have the isnowflake symbol on
the tire wall. Tires with this marking fulfill
the requirements of the Rubber Manufac-
turers Association (RMA) and the Rubber
Association of Canada (RAC). These tires
have been developed specifically for driv-
ing on snow.
When the electronic speed limiter is set, your vehicle is prevented from exceeding 130 mph
(210 km/h).
The speed rating of tires mounted at the fac- tory may be higher than the maximum speed
that the electronic speed limiter permits.
Make sure that your tires have the required
speed rating, e.g. when buying new tires. Therequired speed rating for your vehicle can be
found in the "Tires" section ( Ypage 256).
Further information about reading tire data
can be obtained from any qualified specialist workshop.
Load index
In addition to the load bearing index, load rat-ing :may be imprinted after the letters that
identify speed rating Bon the sidewall of the
tire ( Ypage 244).
R If no specification is given: no text (as in the
example above), represents a standard
load (SL) tire
R XL or Extra Load: represents a reinforcedtire
R Light Load: represents a light load tire
R C, D, E: represents a load range that
depends on the maximum load that the tire
can carry at a certain pressure
iTire data is vehicle-specific and may devi-
ate from the data in the example.
Maximum load rating
Maximum tire load :is the maximum per-
missible weight for which the tire is approved.
4 Or M+S ifor winter tires.
246Tire labeling
Wheels and tires

Maximum loaded vehicle weight
The maximum weight is the sum of: Rthe curb weight of the vehicle
R the weight of the accessories
R the load limit
R the weight of the factory installed optional
equipment
Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa corre-
sponds to 1 psi. Another unit for tire pressure
is bar. 100 kilopascals (kPa) are the equiva-
lent of 1 bar.
Load index
In addition to the load-bearing index, the load index may also be imprinted on the sidewall of
the tire. This specifies the load-bearing capa- city more precisely.
Curb weight
The weight of a vehicle with standard equip-
ment including the maximum capacity of fuel,oil and coolant. It also includes the air-condi- tioning system and optional equipment if
these are installed in the vehicle, but does notinclude passengers or luggage.
Maximum load rating
The maximum load rating is the maximum
permissible weight in kilograms or lbs for
which a tire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for one tire.
Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the maximum axle load of one axleby two.
PSI (pounds per square inch)
A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tire pressure
This is pressure inside the tire applying an
outward force to each square inch of the tire's surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascals
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold.
Cold tire pressure
The tires are cold:
R if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
R if the vehicle has not been driven further
than 1 mile (1.6 km)
Tread
The part of the tire that comes into contact
with the road.
Bead
The tire bead ensures that the tire sits
securely on the wheel. There are several steel
wires in the bead to prevent the tire from
coming loose from the wheel rim.
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
Tire labeling249
Wheels and tires
Z