In addition to the warning lamp, a message
appears in the multifunction display. Observe
the information on display messages
( Y
page 262).
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-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
in the ignition lock ( Y
page 132).X
Press the Y or e button on the steering
wheel to select the Serv. menu.X
Press the c or d button to select
Tire Pressure .X
Press the v button.
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
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 Pressure Monitor 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. If this occurs, note that the value dis-
played for the position 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. The yellow
tire pressure warning lamp then lights up. R
If the 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 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 Tire 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 262).
If 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
after a few minutes of driving, and the tire pres-
sures 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 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 define refer-
ence 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 344).350
Tire pressure
Wheels and tires
Speed rating The speed rating is part of the tire identification.
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, luggage and
the drawbar noseweight, if applicable. The gross
vehicle weight must not exceed the gross vehi-
cle weight rating GVWR as specified on the vehi-
cle 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, occupants,
fuel, luggage and the drawbar noseweight, if
applicable). The gross vehicle weight rating is
specified on the vehicle identification plate on
the B-pillar on the driver's side.
Maximum loaded vehicle weight The maximum weight is the sum of: R
the 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 equivalent 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 capacity
more precisely.
Curb weight
The weight of a vehicle with standard equipment
including the maximum capacity of fuel, oil and
coolant. It also includes the air-conditioning sys- tem and optional equipment if these are instal-
led in the vehicle, but does not include passen-
gers or luggage.
Maximum load rating The maximum tire load is the maximum permis-
sible 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 axle by
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 out-
ward force to each square inch of the tire's sur-
face. The tire pressure is specified in pounds per
square inch (psi), in kilopascal (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 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)
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.360
All about wheels and tires
Wheels and tires
be required earlier. Do not change the direction
of wheel rotation.
Clean the contact surfaces of the wheel and the
brake disc thoroughly every time a wheel is rota-
ted. Check the tire pressure and, if necessary,
restart the tire pressure loss warning system or
the tire pressure monitor ( Y
page 348).
Direction of rotation Tires with a specified direction of rotation have
additional benefits, e.g. if there is a risk of hydro-
planing. These advantages can only be gained if
the tires are installed corresponding to the
direction of rotation.
An arrow on the sidewall of the tire indicates its
correct direction of rotation.
Storing wheels Store wheels that are not being used in a cool,
dry and preferably dark place. Protect the tires
from oil, grease, gasoline and diesel.
Mounting a wheel
Preparing the vehicle X
Vehicle with emergency spare wheel:
when mounting the emergency spare wheel in
the event of a flat tire, follow the additional
notes on vehicle preparation under "Flat tire"
( Y
page 326).X
Stop the vehicle on solid, non-slippery and
level ground. X
Apply the electric parking brake manually. X
Bring the front wheels into the straight-ahead
position. X
Vehicles with automatic transmission:
shift the automatic transmission to position
P . X
Vehicles with the AIRMATIC package:
make sure that the normal vehicle level is
selected ( Y
page 182).X
Vehicles with the Off-Road Engineering
package: make sure that the normal vehicle
level is selected ( Y
page 176).X
Switch off the engine. X
Vehicles without KEYLESS-GO: remove the
SmartKey from the ignition lock. X
Vehicles with KEYLESS-GO: open the driv-
er's door.
The on-board electronics now have status 0 .
This is the same as the SmartKey having been
removed. X
Vehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock
( Y
page 132). X
Make sure that the engine cannot be started
via your smartphone ( Y
page 134).X
If included in the vehicle equipment, remove
the tire-change tool kit from the vehicle. X
Safeguard the vehicle against rolling away.
i Apart from certain country-specific varia-
tions, vehicles are not equipped with a tire-
change tool kit. For information on which
tools are required to perform a wheel change
on your vehicle, consult an authorized
Mercedes-Benz Center.
Necessary tire-changing tools can include, for
example: R
Jack R
Wheel chock R
Lug wrench
Securing the vehicle to prevent it from
rolling away
If your vehicle is equipped with a wheel chock, it
can be found in the tire-change tool kit
( Y
page 326).
The folding wheel chock is an additional safety
measure to prevent the vehicle from rolling
away, for example when changing a wheel. X
Fold both plates upwards C .X
Fold out lower plate D .X
Guide the lugs on the lower plate fully into the
openings in base plate