operating conditions, i.e. differing load and
speed conditions. Example: tire pressure table with tire dimensions
If a tire size precedes a tire pressure, the tirepressure information following is only valid
for that tire size. The load conditions "partially
laden" and "fully laden" are defined in the
table for different numbers 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. The rim diameter is part of the tire size
and can be found on the tire sidewall
(Y page 417).
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:
R if you want to drive with an increased load
and/or
R if you want to drive at higher road speeds
i 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 sudden loss of pressure.
For more information, contact a qualified spe- cialist workshop. Important notes on tire pressure
G
WARNING
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. R Check the tire for foreign objects.
R Check 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. G
WARNING
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 electronic tire pressure monitoring sys-
tem, the tire pressure can be checked using
the on-board computer.
The tire temperature and pressure increase
when the vehicle is in motion. This is depend-
ent on the driving speed and the load.
Therefore, you should only correct tire pres-
sures when the tires are cold. Tire pressure
405Wheels and tires Z
when adjusting the tire pressure
(Y
page 404).
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration. Checking the tire pressures
Important safety notes Observe the notes on tire pressure
(Y
page 404).
Information on air pressure for the tires on
your vehicle can be found:
R on the vehicle's Tire and Loading Informa-
tion placard on the B-pillar (Y page 412)
R on the tire pressure label on the fuel filler
flap (Y page 179)
R in the "Tire pressure" section
R under "Tire pressure" (Y page 404)
Checking tire pressures manually To determine and set the correct tire pres-
sure, proceed as follows:
X Remove the valve cap of the tire that is to
be checked.
X Press the tire pressure gauge securely onto
the valve.
X Read the tire pressure and compare it with
the recommended value on the Tire and
Loading Information placard (Y page 404).
X If the tire pressure is too low, increase it to
the recommended value.
X If the tire pressure is too high, release air by
pressing down the metal pin in the valve.
Use the tip of a pen, for example. Then,
check the tire pressure again using the tire
pressure gauge.
X Screw the valve cap onto the valve.
X Repeat these steps for the other tires. Tire pressure loss warning system
General notes While the vehicle is in motion, the tire pres-
sure loss warning system monitors the set
tire pressure 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 dis- play.
You can recognize the tire pressure loss warn-
ing by the Run Flat Indicator Active Run Flat Indicator Active
Press 'OK' to Restart
Press 'OK' to Restart message which
appears in the Service
Servicemenu of the multi-
function display. Information on the message
display can be found in the "Restarting the tire
pressure loss warning system" section
(Y page 408).
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 (Y page 404).
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 pressure 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 maneuvers.
The function of the tire pressure loss warning system is limited or delayed if:
R snow chains are mounted on your vehicle's
tires.
R road conditions are wintry.
R you are driving on sand or gravel. Tire pressure
407Wheels and tires Z
R
you adopt a very sporty driving style (cor-
nering at high speeds or driving with high
rates of acceleration).
R you are towing a very heavy or large trailer.
R you are driving with a heavy load (in the
vehicle or on the roof).
Restarting the tire pressure loss warn-
ing system Restart the tire pressure loss warning system
if you have:
R changed the tire pressure
R changed the wheels or tires
R mounted new wheels or tires
X Before restarting, make sure that the tire
pressures are set properly on all four tires
for the respective operating conditions.
The recommended tire pressures can be
found on the Tire and Loading Information
placard on the B-pillar on the driver's side
or the tire pressure table on 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.
X Also observe the notes in the section on tire
pressures (Y page 404).
X Make sure that the SmartKey is in position
2 in the ignition lock (Y page 157).
X Press the 0059or0065 button on the steer-
ing wheel to select the Service
Service menu.
X Press the 0063or0064 button to select
Tire Pressure
Tire Pressure.
X Press the 0076button.
The Run Flat Indicator Active Run Flat Indicator Active
Press 'OK' to Restart
Press 'OK' to Restart message
appears in the multifunction display. If you wish to confirm the restart:
X Press the 0076button.
The Tire Pressure Now OK? Tire Pressure Now OK? message
appears in the multifunction display.
X Press the 0063or0064 button to select
Yes Yes .
X Press the 0076button.
The Run Flat Indicator Restarted
Run Flat Indicator Restarted
message appears in the multifunction dis-
play.
After a teach-in period, the tire pressure
loss warning system will monitor the set
tire pressures of all four tires.
If you wish to cancel the restart:
X Press the 0038button.
or
X If the Tire Pressure Now OK? Tire Pressure Now OK? message
appears, use the 0063or0064 button to
select Cancel
Cancel .
X Press the 0076button.
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 pres-
sure monitor warns you if the pressure drops
in one or more of the tires. The tire pressure
monitor only functions if the correct sensors
are installed on all wheels.
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 Service Servicemenu of the mul-
tifunction display. 408
Ti
re pressureWhe els and tires
Example: current tire pressure display
For information on the message display, refer to the "Checking the tire pressure electroni-
cally" section (Y page 410).
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 that recommended for cold tires
which is suitable for the operating situation
(Y page 404). 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 the pressure of the cold tires
(Y page 411). The current pressures are
saved as new reference values. As a result, a
warning message will appear if the tire pres-
sure drops significantly.
The tire pressure monitor does not warn you
of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(Y page 404).
The tire pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the Tire pressure
409Wheels and tires Z
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 maneuvers.
The tire pressure monitor has a yellow warn-
ing lamp in the instrument cluster for indicat- ing a pressure loss or malfunction. Whether
the warning lamp flashes or lights up indi-
cates 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 if the warning lamp flashes for around a
minute and then remains lit constantly, the
tire pressure monitor is malfunctioning.
i In addition to the warning lamp, a mes-
sage appears in the multifunction display.
Further information can be found on
(Y page 312).
If the tire pressure monitor is malfunctioning,
it may take more than ten minutes for the tire pressure warning lamp to inform you of the
malfunction by flashing for approximately one
minute and then remaining lit. When the mal- function 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. Checking the tire pressure electroni-
cally X
Make sure that the SmartKey is in position
2 (Y page 157) in the ignition lock.
X Press the 0059or0065 button on the steer-
ing wheel to select the Service
Service menu.
X Press the 0063or0064 button to select
Tire Pressure Tire Pressure.
X Press the 0076button.
The current tire pressure of each tire is
shown in the multifunction display.
If the vehicle has been parked for longer than 20 minute s,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 Pressure
Monitor Active Monitor Active display message is shown
instead of the tire pressure display. The tire
pressures are already being monitored.
i 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 displayed for the posi-
tion 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 and the yellow tire pressure monitor warning lamp
comes on.
R If the Please Correct Tire Pressure Please Correct Tire Pressure
message appears in the multifunction dis-
play, the tire pressure in at least one tire is 410
Tire pressureWheels and tires
too low and must be corrected at the next
opportunity.
R 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.
R If the Warning Tire Malfunction Warning Tire Malfunction
appears in the multifunction display, the
tire pressure in one or more tires has drop- ped 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 displayedfor 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. The tire pressure monitor
then monitors the new tire pressure values.
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 404).
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 404).
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.
X Press the 0059or0065 button on the steer-
ing wheel to select the Service
Service menu. X
Press the 0063or0064 button to select
Tire Pressure Tire Pressure.
X Press the 0076button.
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 0064button.
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 0076button.
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.
If you wish to cancel the restart:
X Press the 0038button.
The tire pressure values stored at the last
restart will continue to be monitored.
Radio type approval for the tire pres-
sure monitor Country Radio type approval number
USA FCC ID: MRXMW2433A
FCC ID: MRXGG4
FCC ID: MRXMC34MA4
Canada IC: 2546A-MW2433A
IC: 2546A-GG4
IC: 2546A-MC34MA4 Tire pressure
411Wheels and tires Z
Example: steps 1 to 3
The following table shows examples on how to calculate total and cargo load capacities with varying seating configurations and number and size of occupants. The following examples usea maximum load of 1,500 lbs (680 kg). This is for illustration purposes only. Make sure you
are using the actual load limit for your vehicle stated on your vehicle's Tire and Loading Infor- mation placard (Y page 412).
The greater the combined weight of the occupants, the lower the maximum luggage load.
Additional information when towing a trailer (Y page 257).
Step 1 Example 1 Example 2 Example 3
Combined maximum
weight of occupants
and cargo (data from
the Tire and Loading
Information placard)
1500 lbs (680 kg) 1500 lbs (680 kg) 1500 lbs (680 kg)
Step 2
Example 1 Example 2 Example 3
Number of people in
the vehicle (driver
and occupants)
5 3 1
Distribution of the
occupants
Front: 2
Rear: 3 Front: 1
Rear: 2 Front: 1
Weight of the occu-
pants
Occupant 1: 150 lbs
(68 kg)
Occupant 2: 180 lbs
(82 kg)
Occupant 3: 160 lbs (73 kg)
Occupant 4: 140 lbs
(63 kg)
Occupant 5: 120 lbs
(54 kg) Occupant 1: 200 lbs
(91 kg)
Occupant 2: 190 lbs
(86 kg)
Occupant 3: 150 lbs (68 kg) Occupant 1: 150 lbs
(68 kg) Gross weight of all
occupants
750 lbs (340 kg) 540 lbs (245 kg) 150 lbs (68 kg)414
Loading the vehicleWheels and tires
Step 3
Example 1 Example 2 Example 3
Permissible load
(maximum gross vehi-
cle weight rating from
the Tire and Loading
Information placard
minus the gross
weight of all occu-
pants) 1500 lbs (680 kg)
00F8750 lbs (340 kg) =
750 lbs (340 kg) 1500 lbs (680 kg)
00F8540 lbs (245 kg)
=960 lbs (435 kg) 1500 lbs (680 kg)
00F8150 lbs (68 kg) =
1350 lbs (612 kg)
Vehicle identification plate
Even if you have calculated the total cargo
carefully, you should still make sure that the
gross vehicle weight rating and the gross axle weight rating are not exceeded. Details can
be found on the vehicle identification plate on the B-pillar on the driver's side of the vehicle
(Y page 412).
Permissible gross vehicle weight: the
gross weight of the vehicle, all passengers,
load and trailer load/noseweight (if applica-
ble) must not exceed the permissible gross
vehicle weight.
Gross axle weight rating: the maximum per-
missible weight that can be carried by one
axle (front or rear axle).
To ensure that your vehicle does not exceed
the maximum permissible values (gross vehi-
cle weight and maximum gross axle weight
rating), have your loaded vehicle (including
driver, occupants, cargo, and full trailer load if applicable) weighed on a suitable vehicle
weighbridge. Trailer load/noseweight
The trailer load/noseweight affects the gross
weight of the vehicle. If a trailer is attached,
the trailer load/noseweight is included in the
load along with occupants and luggage. The
trailer load/noseweight is usually approx-
imately 8% of the gross weight of the trailer
and its cargo. All about wheels and tires
Uniform Tire Quality Grading Stand-
ards
Overview of Tire Quality Grading Stand- ards Uniform Tire Quality Grading Standards are
U.S. government specifications. Their pur-
pose is to provide drivers with uniform relia-
ble information on tire performance data. Tire
manufacturers have to grade tires using three
performance factors: 0043tread wear grade, 0044
traction grade and 0087temperature grade.
These regulations do not apply to Canada.
Nevertheless, all tires sold in North America
are provided with the corresponding quality
grading markings on the sidewall of the tire.
Where applicable, the tire grading informa-
tion can be found on the tire sidewall between
the tread shoulder and maximum tire width. All about wheels and tires
415Wheels and tires Z