332 OperationTires and wheelsTire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another metric unit for air pressure. There
are 14.5038 pounds per square inch (psi)
to 1 bar; there are 100 kilopascals (kPa)
to 1 bar.
Bead
The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the
rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle
has been sitting for at least 3 hours or driv-
en no more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.DOT (D
epartment o
f T
ransportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross A
xle W
eight R
ating)
The GAWR is the maximum permissible
axle weight. The gross vehicle weight on
each axle must never exceed the GAWR for
the front and rear axle indicated on the
certification label located on the driver’s
door B-pillar.
GVW (G
ross V
ehicle W
eight)
The GVW comprises the weight of the
vehicle including fuel, tools, spare wheel,
installed accessories, passengers and
cargo and, if applicable, trailer tongue
load. The GWV must never exceed the
GWVR indicated on the certification label
located on the driver’s door B-pillar.
333 Operation
Tires and wheels
GVWR (G
ross V
ehicle W
eight R
ating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passen-
gers, fuel, and cargo and, if applicable,
trailer tongue load). It is indicated on
certification label located on the driver’s
door B-pillar.
Kilopascal (kPa)
The metric unit for air pressure. There are
6.9 kPa to 1 psi; another metric unit for air
pressure is bars. There are 100 kilopascals
(kPa) to 1 bar.
Maximum load rating
The maximum load in kilograms and
pounds that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
vehicle capacity weight and production
options weight.Maximum tire inflation pressure
This number is the greatest amount of air
pressure that should ever be put in the tire
under normal driving conditions.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by
68 kilograms (150 lbs).
Occupant distribution
The distribution of occupants in a vehicle
at their designated seating positions.
Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.PSI (P
ounds per s
quare i
nch)
A standard unit of measure for air pressure
-> bar, kilopascal (kPa).
Recommended tire inflation pressure
Recommended tire inflation pressure
listed on placard located on driver’s door
B-pillar for normal driving conditions.
Provides best handling, tread life and
riding comfort.
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
Sidewall
The portion of a tire between the tread and
the bead.
335 Operation
Tires and wheels
Rotating tires
Tire rotation can be performed on vehicles
with tires of the same dimension all
around. If your vehicle is equipped with
tires of the same dimension all around,
tires can be rotated, observing a
front-to-rear rotation pattern that will
maintain the intended rotation (spinning)
direction of the tire (
page 304).In some cases, such as when your vehicle
is equipped with mixed-size tires (different
tire dimension front vs. rear), tire rotation
is not possible.
If applicable to your vehicle’s tire configu-
ration, tires can be rotated according to
the tire manufacturer's recommended in-
tervals in the tire manufacturer's warranty
pamphlet located in your vehicle literature
portfolio. If none is available, tires should
be rotated every 3000 to 6 000 miles
(5 000 to 10 000 km), or sooner if neces-
sary, according to the degree of tire wear.
The same rotation (spinning) direction
must be maintained (
page 304).Rotate tires before the characteristic tire
wear pattern becomes visible (shoulder
wear on front tires and tread center wear
on rear tires).
Thoroughly clean the mounting face of
wheels and brake disks, i.e. the inner side
of the wheels/tires, during each rotation.
Check for and ensure proper tire inflation
pressure.
For information on wheel change, see the
“Practical hints” section (
page 398) and
(
page 419).
Warning!
G
Rotate front and rear wheels only if they are
of the same size.
If your vehicle is equipped with mixed-size
tires (different tire dimensions front vs.
rear), tire rotation is not possible.
Warning!
G
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
96 lb-ft (130 Nm).
Only use Genuine Mercedes-Benz wheel
bolts specified for your vehicle’s rims.
351 Practical hints
What to do if …
Where will I find ...?
Unlocking/locking in an emergency
Opening/closing in an emergency
Resetting activated head restraints
Replacing SmartKey batteries
Replacing bulbs
Replacing wiper blades
Flat tire
Battery
Jump starting
Towing the vehicle
Fuses
360 Practical hintsWhat to do if …Problem
Possible cause/consequence
Suggested solution
H
Combination low tire
pressure/TPMS malfunction tell-
tale for the Advanced TPMS* illu-
minates continuously.
The Advanced TPMS* detects a loss of pres-
sure in at least one tire.
Carefully bring the vehicle to a halt,
avoiding abrupt steering and braking
maneuvers. Observe the traffic situa-
tion around you.
Read and observe messages in the
multifunction display.
If the tire inflation pressure in the respec-
tive tire(s) has (have) been corrected, the
combination low tire pressure/TPMS
malfunction telltale goes out after few
minutes driving.
H
Combination low tire
pressure/TPMS malfunction tell-
tale for the Advanced TPMS*
flashes for 60 seconds and then
stays illuminated.
There is a malfunction in the Advanced
TPMS*.
Read and observe messages in the
multifunction display.
Have the Advanced TPMS* checked
by an authorized Mercedes-Benz Cen-
ter.
After the malfunction has been remedied
the combination low tire pressure/TPMS
malfunction telltale goes out after few
minutes driving.
361 Practical hints
What to do if …
Warning!
G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle placard or the tire inflation pressure
label. (If your vehicle has tires of a different
size than the size indicated on the vehicle
placard or the tire inflation pressure label,
you should determine the proper tire infla-
tion pressure for those tires).
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires is significantly under-inflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible, and inflate them to
the proper pressure. Driving on a significant-
ly under-inflated tire causes the tire to over-
heat and can lead to tire failure.
Under-inflation also reduces fuel efficiency
and tire tread life, and may affect the vehi-
cle’s handling and stopping 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 under-inflation has not
reached the level to trigger illumination of
the TPMS low tire pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate
when the system is not operating properly.
The TPMS malfunction indicator is com-
bined with the low tire pressure telltale.
When the system detects a malfunction, the
telltale will flash for approximately
one minute and then remain continuously
illuminated. This sequence will continue
upon subsequent vehicle start-ups as long
as the malfunction exists. When the mal-
function indicator is illuminated, the system
may not be able to detect or signal low tire
pressure as intended.
TPMS malfunctions may occur for a variety
of reasons, including the installation of in-
compatible replacement or alternate tires or
wheels on the vehicle that prevent the TPMS
from functioning properly. Always check the
TPMS malfunction 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 properly.
370 Practical hintsWhat to do if …Display messages
Possible cause/consequence
Possible solution
Please note:
Conven. functions
available again
On-board voltage is sufficient; the
consumers will switch on again.
Run Flat Indicator
inactive
Run Flat Indicator* is
malfunctioning.
Have the Run Flat Indicator* checked by an
authorized Mercedes-Benz Center.
Check tires
Then reactivate
Run Flat Indicator
There was a warning message about
a loss in the tire inflation pressure
and the Run Flat Indicator* has not
been reactivated yet.
Make sure that the correct tire inflation pres-
sure is set for each tire.
Then reactivate the Run Flat Indicator*.
Run Flat Indicator
unavailable
The Run Flat Indicator* has been
switched off due to an error.
Have the Run Flat Indicator* checked by an
authorized Mercedes-Benz Center.
Tire pressure
Check tires
The Run Flat Indicator* indicates
that the pressure is too low in one or
more tires.
Carefully bring the vehicle to a halt, avoiding
abrupt steering and braking maneuvers. Ob-
serve the traffic situation around you.
Check and adjust tire inflation pressure as
required (
page 313).
If necessary, change the wheel (
page 423).
Reactivate the Run Flat Indicator* after adjust-
ing the tire inflation pressure values
(page 315).
371 Practical hints
What to do if …
Display messages
Possible cause/consequence
Possible solution
Tire pressure
displayed only
after driving a
few minutes
The tire inflation pressure is being
checked.
Drive the vehicle for a few minutes.
Tire pres. monitor
currently unavailable
The Advanced TPMS* is unable to
monitor the tire pressure due to
a nearby radio interference
source.
excessive wheel sensor temper-
atures.
As soon as the causes for the malfunction are
no longer present, the Advanced TPMS* auto-
matically becomes active again after a few
minutes driving.
Tire pres. monitor
inoperative
The Advanced TPMS* is
malfunctioning.
Have the Advanced TPMS* checked by an au-
thorized Mercedes-Benz Center.