Page 416 of 462

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 tire pressure monitor has a yellow warn-
ing lamp in the instrument cluster for indicat-
ing pressure loss or a 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:
Rif 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.
Rif the warning lamp flashes for around 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
(
Ypage 318).
It may take up to ten minutes for a malfunc-
tion of the tire pressure monitor to be indica-
ted. A malfunction will be indicated by the tire
pressure warning lamp flashing for approx-
imately 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 gage.
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 gage 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
XMake sure that the SmartKey is in position
2 in the ignition lock (
Ypage 165).
XPress the =or; button on the steer-
ing wheel to select the Service
menu.
XPress the9or: button to select
Tire Pressure
.
XPress the abutton.
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
minutesmessage 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
Monitor Activedisplay message 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 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.
RIf the Please Correct Tire Pressure
message appears in the multifunction dis-
play, the tire pressure in at least one tire is
414Tire pressure
Wheels and tires
Page 423 of 462

Tire labeling
Overview
:Uniform Tire Quality Grading Standards
(
Ypage 425)
;Department of Transportation, Tire Iden-
tification Number (
Ypage 424)
=Maximum load rating (Ypage 423)
?Maximum tire pressures (Ypage 411)
AManufacturer
BTire material (Ypage 424)
CTire size designation, load-bearing capa-
city and speed rating (
Ypage 421)
DLoad index (Ypage 423)
ETire name
The markings described above are on the tire
in addition to the tire name (sales designa-
tion) and the manufacturer's name.
iTire data is vehicle-specific and may devi-
ate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating
GWARNING
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
;Nominal aspect ratio in %
=Tire code
?Rim diameter
ALoad bearing index
BSpeed rating
General: depending on the manufacturer's
standards, the size imprinted in the tire wall
may not contain any letters or may contain
one letter that 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.
manufacturing standards.
If "LT" precedes the size description: these
are light truck tires according to U.S. manu-
facturing standards.
If "T" precedes the size description: compactemergency wheels with high tire pressure
that are only designed for temporary use in an
emergency.
Tire width: tire width:shows the nominal
tire width in millimeters.
Height-width ratio: aspect ratio;is the
size ratio between the tire height and tire
width and is shown in percent. The aspect
All about wheels an d tires421
Wheels and tires
Z
Page 431 of 462

XOn light downhill gradients:place
chocks or other suitable items in front of
the wheels of the front and rear axle.
Raising the vehicle
GWARNING
If you do not position the jack correctly at the
appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle.
!AMG vehicles with "Minispare" emer-
gency spare wheel: use the "Minispare"
emergency spare wheel only on the rear
axle. If you mount the "Minispare" emer-
gency spare wheel on the front axle, this
could result in damage to the brake system.
If a tire on the front axle is defective, an
intact wheel from the rear axle must first be
replaced with the "Minispare" emergency
spare wheel. The faulty wheel on the front
axle may only then be replaced by the
undamaged wheel from the rear axle.
Make sure to note the placard on the
"Minispare" emergency spare wheel.
!The jack is designed exclusively for jack-
ing up the vehicle at the jacking points.
Otherwise, your vehicle could be damaged. Observe the following when raising the vehi-
cle:
RTo raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If used incor-
rectly, the jack could tip over with the vehi-
cle raised.
RThe jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suited for per-
forming maintenance work under the vehi-
cle.
RAvoid changing the wheel on uphill and
downhill slopes.
RBefore raising the vehicle, secure it from
rolling away by applying the parking brake
and inserting wheel chocks. Do not disen-
gage the parking brake while the vehicle is
raised.
RThe jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, flat, load-bearing underlay must be
used. On a slippery surface, a non-slip
underlay must be used, e.g. rubber mats.
RDo not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able t
o achieve its load-
bearing capacity due to the restricted
height.
RMake sure that the distance between the
underside of the tires and the ground does
not exceed 1.2 in (3 cm).
RDo not place your hands or feet under the
raised vehicle.
RDo not lie under the vehicle.
RDo not start the engine when the vehicle is
raised.
RNever open or close a door or the tailgate
when the vehicle is raised.
RMake sure that no persons are present in
the vehicle when the vehicle is raised.
Changing a wheel429
Wheels and tires
Z