2015 MERCEDES-BENZ G-Class tire pressure

Tire pressure monitor
Important safety notes G
WARNING
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, andmay 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 the recommended cold tire pres-
sure suitable for the operating situation
(Y page 309). 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 is aligned to the reference values taught-in.
Restart the tire pressure monitor after adjust-
ing to the cold tire pressure (Y page 315).
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 309).
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 Tire pressure
313Wheels and tires Z

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 atire 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-
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.
i USA 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.
i Canada 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 interferencereceived, 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 (Y page 133).
X Press the =or; button on the steer-
ing wheel to select the Serv. Serv.menu.
X Press the 9or: button to select
Tire Pressure
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
Tire pressure will be
displayed after driving a few displayed after driving a few
minutes minutes message 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 Tire Pressure314
Tire pressureWheels and tires

Monitor Active
Monitor Active
display message is shown
instead of the tire pressure display. The tire
pressures are already being monitored.
i If 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 Pressure
Correct Tire Pressure message
appears in the multifunction display, check the tire pressure on all four wheels and cor-
rect it if necessary.
X If the Check
Check Tires Tiresmessage 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 Press. Warning Caution
Tire Malfunction
Tire Malfunction message appears in
the multifunction display, the tire pressure in one or more tires has dropped suddenly
and the tires must be checked.
i If the wheel positions on the vehicle are
rotated, the tire pressures may be dis-
played for the wrong positions for a short
time. This is rectified after a few minutes of driving, and the tire pressures 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 currently set tire pressures as the refer-
ence values for monitoring. In most cases, the
tire pressure monitor will automatically
detect the new reference values after you
have changed the tire pressure. However, you
can also define reference values manually as described here.
X Set the tire pressure to the value recom-
mended for the corresponding driving sit-
uation on the Tire and Loading Information
placard on the driver's side
B-pillar (Y page 309).
Additional tire pressure values for different loads can also be found on the tire pressure table on the inside of the fuel filler flap
(Y page 309).
X Make sure that the tire pressure is correct
on all four wheels.
X Make sure that the SmartKey is in position
2 in the ignition lock (Y page 133).
X Press the =or; button on the steer-
ing wheel to select the Serv. Serv.menu.
X Press the 9or: button to select
Tire Pressure
Tire Pressure.
X Press the abutton.
The multifunction display shows the cur-
rent tire pressure for the individual tires or
the Tire
Tire pressure
pressure will
willbe
bedisplayed
displayed
after driving a few minutes
after driving a few minutes mes-
sage.
X Press the :button.
The Use Current Pressures as New
Use Current Pressures as New
Reference Values
Reference Values message appears in
the multifunction display.
If you wish to confirm the restart:
X Press the abutton.
The Tire Press. Monitor Restarted
Tire Press. Monitor Restarted
message appears in the multifunction dis-
play.
After driving for a few minutes, the system
checks whether the current tire pressures
are within the specified range. The new tire
pressures are then accepted as reference
values and monitored. Tire pressure
315Wheels and tires Z

If you wish to cancel the restart:
X Press the %button.
The tire pressure values stored at the last
restart will continue to be monitored. Loading the vehicle
Instruction labels for tires and loads
G
WARNING
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. :
B-pillar, driver's side
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 occupants and the maximum permis-
sible vehicle load. It also contains details
of the tire sizes and corresponding pres-
sures for tires mounted at the factory.
(2) The vehicle identification plate is on the B-pillar on the driver's side. The vehicle
identification plate informs you of the
gross vehicle weight rating. It is made up
of the vehicle weight, all vehicle occu- pants, the fuel and the cargo. You can
also find information 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). Do not
exceed the maximum gross vehicle
weight or the maximum gross axle weight
rating for the front or rear axle. Maximum permissible gross mass
X
Specification for maximum permissible
load :is listed on the Tire and Loading
Information placard: "The combined weight of occupants and cargo should never
exceed XXX kilograms or XXX lbs."
The gross weight of all vehicle occupants,
cargo, luggage and trailer load/noseweight (if
applicable) must not exceed the specified
value.
i The specifications shown on the Tire and
Loading Information placard in the illustra- tion are examples. The maximum permis-
sible load is vehicle-specific and may devi-
ate from the data shown here. The maxi-
mum permissible load that applies for your vehicle can be found on your vehicle's Tire
and Loading Information placard. 316
Loading the vehicleWheels and ti
res

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. Tire labeling
Overview of tire labeling
:
Uniform tire Quality Grading Standard
(Y page 325)
; DOT tire Identification Number
(Ypage 324)
= Maximum tire load (Y page 323)
? Maximum tire pressures (Y page 312)
A Manufacturer
B Tire material (Y page 324)
C Tire size designation, load-bearing capa-
city and speed rating (Y page 321)
D Load identification (Y page 323)
E Tire name
The markings described above are on the tire in addition to the tire name (sales designa-
tion) and the manufacturer's name.
i Tire data is vehicle-specific and may devi-
ate from the data in the example. Tire size designation, load-bearing
capacity and speed rating
G
WARNING
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
A Load bearing index
B Speed 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 Tire labeling
321Wheels and tires Z

pressure, to be used only temporarily in an
emergency.
Tire width: tire width:shows the nominal
tire width in millimeters.
Height-width ratio: height-width ratio;is
the ratio between tire height and tire width.
The aspect ratio is calculated by dividing the
tire width by the tire height. The resulting
quotient is given as a percentage.
Tire code: tire code=shows the tire type.
"R" represents radial tires; "D" represents
diagonal 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 description, depending on the man-
ufacturer (e.g. 245/40 ZR 18).
Rim diameter: rim diameter?is the diam-
eter of the bead seat, not the diameter of the
rim flange. The rim diameter is specified in
inches (in).
The load-bearing index: load-bearing index
A (also load index), is a code that contains
the maximum load-bearing capacity of a tire.
Do not overload the tires by exceeding the
specified load limit. The maximum permissi-
ble load can be found on the vehicle's Tire and
Loading Information placard on the B-pillar on the driver's side (Y page 316).
Example:
Load-bearing index 91 indicates a maximum
load of 1,356 lb (615 kg) that the tires can
bear. For further information on the maximum tire load in kilograms and pounds, see
(Y page 323).
For further information on the load bearing
index, see "Load index" (Y page 323).
Speed rating: speed ratingBspecifies the
approved maximum speed of the tire.
i Tire data is vehicle-specific and may devi-
ate from the data in the example.
Regardless of the speed rating, always
observe the speed limits. Drive carefully and
adapt your driving style to the traffic condi-
tions. i
Since 2009, tires in Europe which corre-
spond to the noise limitations of Directive
ECE-R 117 show an >>S<< (Sound) mark.
This identification follows the type approval number and has no connection with the
speed rating.
Summer tires Index Speed rating
Q up to 100 mph (160 km/h)
R up to 106 mph (170 km/h)
S up to 112 mph (180 km/h)
T up to 118 mph (190 km/h)
H up to 130 mph (210 km/h)
V up to 149 mph (240 km/h)
W up to 168 mph (270 km/h)
Y up to 186 mph (300 km/h)
ZR...Y up to 186 mph (300 km/h)
ZR...(..Y) over 186 mph (300 km/h)
ZR over 149 mph (240 km/h)
R
Optionally, tires with a maximum speed of
over 149 mph (240 km/h) may have "ZR" in the size description, depending on the
manufacturer (e.g. 245/40 ZR18).
The service specification is made up of
load-bearing index Aand speed rating B.
R If the size description of your tire includes
"ZR" and there are no service specifica-
tions, ask the tire manufacturer in order to
find out the maximum speed.
If a service specification is available, the
maximum speed is limited according to the
speed rating in the service specification.
Example: 245/40 ZR18 97 Y.In this exam-
ple, "97 Y" is the service specification. The letter "Y" represents the speed rating and 322
Tire labelingWheels 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 Index Speed rating
Q M+S
4 up to 100 mph (160 km/h)
T M+S
4 up to 118 mph (190 km/h)
H M+S
4 up to 130 mph (210 km/h)
V M+S
4 up to 149 mph (240 km/h)
i
Not 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. The required speed rating for your vehicle can be
found in the "Tires" section (Y page 333).
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 (Y page 321).
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 reinforced
tire
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
i Tire 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. Tire labeling
323Wheels and tires Z

Bar
Metric unit for tire pressure. 14.5038 pounds
per square inch (psi) and 100 kilopascals
(kPa) are the equivalent of 1 bar.
DOT (Department of Transportation) DOT-marked tires fulfill the requirements of
the U S Department of Transportation.
Normal occupant weight The number of occupants for which the vehi-
cle is designed multiplied by 68 kilograms
(150 lbs).
Uniform Tire Quality Grading Standards A uniform standard to grade the quality of
tires with regards to tread quality, tire traction
and temperature characteristics. The quality
grading assessment is made by the manufac- turer following specifications from the U.S.
government. The ratings are molded into the
sidewall of the tire.
Recommended tire pressures The recommended tire pressure applies to
the tires mounted at the factory.
The Tire and Loading Information placard con- tains the recommended tire pressures for
cold tires on a fully loaded vehicle and for themaximum permissible vehicle speed.
The tire pressure table contains the recom-
mended pressures for cold tires for various
operating conditions, i.e. differing load and
speed conditions.
Increased vehicle weight due to
optional equipment The combined weight of all standard and
optional equipment available for the vehicle,
regardless of whether it is actually installed
on the vehicle or not. Rim This is the part of the wheel on which the tire
is mounted.
GAWR (Gross Axle Weight Rating) The GAWR is the maximum gross axle weight
rating. The actual load on an axle must never
exceed the gross axle weight rating. The
gross axle weight rating can be found on the
vehicle identification plate on the B-pillar on
the driver's side.
Speed rating The speed rating is part of the tire identifica-
tion. It specifies the speed range for which the
tire is approved.
GTW (Gross Trailer Weight) The GTW is the weight of a trailer including the
weight of the load, luggage, accessories etc.
on the trailer.
GVW (Gross Vehicle Weight) The gross vehicle weight includes the weight
of the vehicle including fuel, tools, the spare
wheel, accessories installed, occupants, lug-
gage and the drawbar noseweight, if applica-
ble. The gross vehicle weight must not exceed the gross vehicle weight rating GVWR as
specified on the vehicle identification plate on
the B-pillar on the driver's side.
GVWR (Gross Vehicle Weight Rating) The GVWR is the maximum permissible gross
weight of a fully loaded vehicle (the weight of the vehicle including all accessories, occu-
pants, fuel, luggage and the drawbar nose-
weight, if applicable). The gross vehicle
weight rating is specified on the vehicle iden-
tification plate on the B-pillar on the driver's
side. Tire labeling
325Wheels and tires Z