
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 342).
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 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
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 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:
R if the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and
R if 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:
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
R in the tire pressure table in the fuel filler flap
(Y page 143)
R printed in yellow on the rim of the emer-
gency/collapsible spare wheel (depending on
vehicle equipment) Underinflated or overinflated tires
Underinflated tires G
WARNING
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. 332
Tire pressureWheels and tires

Avoid tire pressures that are too low in all the
tires, including the spare wheel.
Underinflated tires may:
R overheat, leading to tire defects
R adversely affect handling
R wear excessively and/or unevenly
R have an adverse effect on fuel consumption
Overinflated tires G
WARNING
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: R increase the braking distance
R adversely affect handling
R wear excessively and/or unevenly
R have an adverse effect on ride comfort
R be more susceptible to damage
Maximum tire pressures 0043
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 (Y page 330).i
The 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
(Y
page 330).
Information on air pressure for the tires on your vehicle can be found:
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
R in the tire pressure table in the fuel filler flap
R in the "Tire pressure" section
Checking tire pressures manually To determine and set the correct tire pressure,
proceed as follows:
X Remove the valve cap of the tire that is to be
checked.
X Press the tire pressure gage securely onto the
valve.
X Read the tire pressure and compare it to the
recommended value on the Tire and Loading
Information placard or the tire pressure table
(Y page 330).
X If the tire pressure is too low, increase the tire
pressure to the recommended value.
X If 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.
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 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, Tire pressure
333Wheels and tires Z

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 Run Flat Indicator Active Press
'OK' to Restart
'OK' to Restart message which appears in
the Service
Service menu of the multifunction display.
Information on the message display can be
found in the "Restarting the tire pressure loss
warning system" section (Y page 334).
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 330).
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:
R snow chains are mounted on your vehicle's
tires.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style (corner-
ing at high speeds or driving with high rates of
acceleration).
R you 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 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 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.
X Also observe the notes in the section on tire
pressures (Y page 330).
X Make sure that the SmartKey is in position 0048
in the ignition lock (Y page 127).
X Press the 0059or0065 button on the steering
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 Press
Run Flat Indicator Active Press
'OK' to Restart
'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 mes-
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: X Press the 0038button.
or
X When the Tire
TirePressure
Pressure Now
NowOK?
OK?message
appears, press 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 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. 334
Tire pressureWheels and tires

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 Serv.
Serv. menu of the multifunction
display, see illustration (example). For information on the message display, refer to
the "Checking the tire pressure electronically"
section (Y page 336).
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, 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
(Y page 330). 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 (Y page 337). 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
(Y page 330).
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 Tire pressure
335Wheels and tires Z

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:
R if 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.
R if 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
(Y page 245).
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-wayradios) 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 0048
(Y page 127) in the ignition lock.
X Press the 0059or0065 button on the steering
wheel to select the Serv.
Serv. menu. X
Press the 0063or0064 button to select
Tire Pressure Tire Pressure.
X Press 0076.
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 Tire pressure will be
displayed after driving a few minutes
displayed after driving a few minutes
message 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, the Tire
Tire Pressure
Pressure Monitor MonitorActive
Active
display 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. Therefore, remember that the dis-
played tire pressure may not be the same as the
emergency spare wheel's current tire pressure.
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.
R If the Please Correct Tire Pressure
Please Correct Tire Pressure
message 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.
R If the Check Tires Check Tires message appears in the
multifunction display, the tire pressure in at
least one tire has dropped significantly. The
tires must be checked.
R If the Warning Warning Tire
TireMalfunction
Malfunction message
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 (Y page 245).
If the positions of the wheels on the vehicle are changed, the tire pressures may be displayed in
the wrong positions for a short time. This is rec-
tified after a few minutes of driving, and the tire pressures are displayed for the correct posi-
tions. 336
Tire pressureWheels and tires

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.
X Set 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 (Y page 330).
You can find more tire pressure values for
various operating conditions in the tire pres-
sure table inside the fuel filler flap
(Y page 331).
X Make sure that the tire pressure is correct on
all four wheels.
X Make sure that the SmartKey is in position 0048
in the ignition lock.
X Press the 0059or0065 button on the steering
wheel to select the Serv. Serv.menu.
X Press the 0063or0064 button to select
Tire Pressure
Tire Pressure .
X Press 0076.
The multifunction display shows the current
tire pressure for the individual tires or the
Tire pressure will be displayed Tire pressure will be displayed
after driving a few minutes after driving a few minutes message.
X Press the 0064button.
The Use
Use Current
Current Pressures
Pressures as
asNew
New Ref‐
Ref‐
erence
erence Values
Valuesmessage appears in the mul-
tifunction display.
If you wish to confirm the restart:
X Press the 0076button.
The Tire
Tire Press.
Press. Monitor
Monitor Restarted
Restarted mes-
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: 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: MRXGG4
FCC ID: MRXMC34MA4
This device complies with Part 15
of the FCC Rules. Operation is
subject to the following two con- ditions: (1) This device may not
cause harmful interference, and
(2) This device must accept any
interference received, including
interference that may cause
undesired operation. Canada IC: 2546A-GG4;
IC: 2546A- MC34MA4;
Le présent appareil est conforme
aux CNR d'Industrie Canada
applicables aux appareils radio
exempts de license. L'exploita-
tion est autorisée aux deux con-
ditions suivantes: (1) l'appareil
ne doit pas produire de brouil-
lage, et (2) l'utilisateur de l'ap-
pareil doit accepter tout brouil-
lage radioélectrique subi, même
si le brouillage est susceptible
d'en compromettre le fonc-
tionnement. 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.
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 Loading the vehicle
337Wheels and tires Z

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 purpose is to
provide drivers with uniform reliable information on tire performance data. Tire manufacturers
have to grade tires using three performance fac-
tors: 0043tread wear grade, 0044traction grade and
0087 temperature grade. These regulations do not
apply to Canada. Nevertheless, all tires sold in
North America are provided with the corre-
sponding quality grading markings on the side-
wall of the tire.
Quality grades can be found, where applicable,
on the tire sidewall between tread shoulder and
maximum section width.
Example:
R Treadwear grade: 200
R Traction grade: AA
R Temperature grade: A
All passenger car tires must conform to the stat-
utory safety requirements in addition to these
grades.
i The 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 G
WARNING
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 00CFin (4 mm) on all four winter tires.
Observe the legally required minimum tire tread
depth (Y page 328). 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)
(Y page 329).
Temperature G
WARNING
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 All about wheels and tires
341Wheels and tires
Z

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. Tire labeling
Overview 0043
Uniform Tire Quality Grading Standards
(Ypage 345)
0044 Department of Transportation, Tire Identifi-
cation Number (Y page 345)
0087 Maximum load rating (Y page 344)
0085 Maximum tire pressures (Y page 333)
0083 Manufacturer
0084 Tire material (Y page 345)
006B Tire size designation, load-bearing capacity
and speed rating (Y page 342)
006C Load index (Y page 344)
006D Tire name The markings described above are on the tire in
addition to the tire name (sales designation) and the manufacturer's name.
i Tire data is vehicle-specific and may deviate
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. 0043
Tire width
0044 Nominal aspect ratio in %
0087 Tire code
0085 Rim diameter
0083 Load bearing index
0084 Speed rating
General: depending on the manufacturer's
standards, the size imprinted in the tire wall may not contain any letters or may contain one letterthat 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. 342
All about wheels and tiresWheels and tires