The tire pressure monitor hasayellow
warning lamp in the instrument cluster for
indicatingapressure loss or malfunction.
Whether the warning lamp flashes or lights up
indicates whetheratire 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 malfunctioning.
Rif the warning lamp flashes for around a
minute and then remains lit constantly, the
tire pressure monitor is malfunctioning.
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
malfunction has been rectified, the tire
pressure warning lamp goes out afterafew
minutes of driving.
The tire pressure values indicated by the on-
board computer may differ from those
measured atagas station withapressure
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 byapressure gauge are
higher than those shown by the on-board
computer.Inthis case, do not reduce the tire
pressures.
The operation of the tire pressure monitor can
be affected by interference from radio
transmitting equipment (e.g. radio
headphones, two-way radios) that may be
being operated in or near the vehicle.
Checking the tire pressure
electronically
XMake sure that the SmartKey is in position
2(Ypage 147) in the ignition lock .
XPress the \nor button on the
steering wheel to select theServ.menu.
XPress the or button to select
Tire Pressure.
XPress the button.
The current tire pressure of each tire is
shown in the multifunction display.
If the vehicle was parked for longer than
20 minutes,theTirepressureswillbe
displayed after drivingafew
minutesmessage is shown.
Afterateach-in process, the tire pressure
monitor automatically detects new wheels or
new sensors. As long asaclear allocation of
the tire pressure value to the individual
wheels is not possible, theTire Pressure
Monitor Activedisplaymessage is shown
instead of the tire pressure display. The tire
pressures are already being monitored.
iIf an emergency spare wheel is mounted,
the system may continue to show the tire
pressure of the wheel that has been
removed forafew minutes. If this occurs,
note that the value displayed for the
position where the spare wheel is mounted
is not the same as the current tire pressure
of the emergency spare wheel.
Tire pressuremonitor warning
messages
If the tire pressure monitor detectsapressure
loss in one or more tires,awarning message
is shown in the multifunction displayand the
yellow tire pressure monitor warning lamp
comes on.
RIf theCorrect Tire Pressuremessage
appears in the multifunction display, the
tire pressure in at least one tire is too low
and must be corrected at the next
opportunity.
RIf theCheck Tire Pressuremessage
appears in the multifunction display, the
tire pressure in one or more tires has
dropped significantly and the tires must be
checked.
RIf theTire Malfunctionappears in the
multifunction display, the tire pressure in
344Check
Wheels and tires
one or more tires has dropped suddenly
and the tires must be checked.
Observe the instructions and safety notes in
the display messages in the "Tires" section
(Ypage 258).
iIf 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 afterafew
minutes of driving, and the tire pressures
are displayed for the correctpositions.
Restarting the tire pressuremonitor
When you restart the tire pressure monitor,
all existingwarning messages are deleted and
the warning lamps go out. The monitor uses
the currently set tire pressures as the
reference 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.
XSet the tire pressure to the value
recommended for the corresponding
driving situation on the Tire and Loading
Information placard on the B-pillar on the
driver's side (Ypage 338).
Additional tire pressure values for different
loads can also be found on the tire pressure
table on the inside of the fuel filler flap
(Ypage 338).
XMake sure that the tire pressure is correct
on all four wheels.
XMake sure that the SmartKey is in position
2in the ignition lock.
XPress the \nor button on the
steeringwheel to select theServ.menu.
XPress the or button to select
Tire Pressure.
XPress the button.
The multifunction display shows the
current tire pressure for each tire or the
Tire pressures will be displayed
after drivingafew minutes
message.
XPress the button.
The multifunction display shows theUse
CurrentPressuresasNewReference
Valuesmessage.
If you wish to confirm the restart:
XPress the button.
TheTire Press. Monitor Restarted
message appears in the multifunction
display.
After driving forafew minutes, the system
checkswhether 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:
XPress 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
GWARNING
Overloaded tires can overheat, causing a
blowout. Overloaded tires can also impair the
steering and driving characteristics and lead
to brake failure. There isarisk 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 occupantsand the maximum
permissible vehicle load. It also contains
Loading the vehicle345
Wheels and tires
Z
Example:
RTreadweargrade:200
RTractiongrade:AA
RTemperature grade:A
All passengercar tires must conform to the
statutory safety requirements in additionto
these grades.
iTheactual values for tires arevehicle-
specificand maydeviate from the values in
the illustration.
Treadwear
The treadweargrade isacomparative rating
based on the wearrate of thetirewhen tested
undercontrolled conditions onaspecified
U.S. government course. For example,atire
graded 150 would wear one and one-half
times as well on the government course as a
tire graded 100.
The relative performanceoftires 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 climate conditions.
Traction
GWARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
!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 onawet surface as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete.Atire markedCmay have poor
traction performance.
The safe speed onawet, snowcovered or icy
road is always lower than on dry road
surfaces.
You should pay special attention to road
conditions when temperatures are around
freezingpoint.
Mercedes-Benzrecommendsaminimum
tread depthof in(4mm)onall four winter
tires. Observe the legally required minimum
tire tread depth (Ypage335). Winter tires can
reduce the braking distance on snow-covered
surfaces in comparison with summer tires.
The braking distance is still much further than
on surfaces that are not icy or covered with
snow. Take appropriate care when driving.
Further informationonwinter tires (M+S
tires) (Ypage336).
Temperature
GWARNING
The temperature grade for this tire is
established foratire that is properly inflated
and not overloaded. Excessive speed,
underinflation, or excessive loading, either
separately or in combination, can cause
excessive heat build-up and possible tire
failure.
The temperature grades areA(the highest),
B, and C. Theserepresent the tire's
resistancetothe generationofheat and its
ability to dissipate heat when tested under
controlled conditions onaspecified indoor
laboratory test wheel. Sustained high
temperature can cause the material of the tire
to degenerateand reduce tire life, and
excessive temperature can lead to sudden
tire failure. The gradeCcorresponds toalevel
of performancewhich all passenger car tires
must meet under the Federal Motor Vehicle
Safety Standard No. 109. GradesBand A
represent higher levels of performanceonthe
laboratory test wheel than the minimum
required by law.
350All about wheelsand tires
Wheels and tires