324 Operation
Tires and wheels
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
driven 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 (Department of Transportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross Axle Weight Rating)
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 Vehicle Weight)
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 GVW must never exceed the
GVWR indicated on the certification label
located on the driver’s door B-pillar.GVWR (G
ross Vehicle Weight Rating)
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 certi-
fication 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,
total load limit and production options
weight.
325 Operation
Tires and wheels
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 (Pounds per square inch)
A standard unit of measure for air pressure
-> bar, kilopascal (kPa).
Recommended tire inflation pressure
Recommended tire inflation pressure for
normal driving conditions is listed on the
Tire and Loading Information placard locat-
ed on the driver’s door B-pillar. Provides
best handling, tread life and riding com-
fort. If so equipped, supplemental informa-
tion pertaining to special driving situations
can be found on the tire inflation pressure
label on the inside of the fuel filler flap.
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.TIN (Tire Identification Number)
Unique identifier which facilitates efforts
by tire manufacturers to notify purchasers
in recall situations or other safety matters
concerning tires and gives purchases the
means to easily identify such tires. The TIN
is comprised of “Manufacturer’s identifica-
tion mark”, “Tire size”, “Tire type code”
and “Date of manufacture”.
Tire load rating
Numerical code associated with the
maximum load a tire can support.
Tire ply composition and material used
This indicates the number of plies or the
number of layers of rubber-coated fabric in
the tire tread and sidewall. Tire manufac-
turers also must indicate the ply materials
in the tire and sidewall, which include
steel, nylon, polyester, and others.
326 Operation
Tires and wheels
Tire speed rating
Part of tire designation; indicates the
speed range for which a tire is approved.
Total load limit
Rated cargo and luggage load plus
68 kilograms (150 lbs) times the vehicle’s
designated seating capacity.
Traction
Force exerted by the vehicle on the road
via the tires. The amount of grip provided.
Tread
The portion of a tire that comes into
contact with the road.
Treadwear indicators
Narrow bands, sometimes called
“wear bars” that show across the tread of
a tire when only
1/16in (1.6 mm) of tread
remains.Uniform Tire Quality Grading Standards
A tire information system that provides
consumers with ratings for a tire’s traction,
temperature and treadwear. Ratings are
determined by tire manufacturers using
government testing procedures. The
ratings are molded into the sidewall of the
tire.
Vehicle maximum load on the tire
Load on an individual tire that is
determined by distributing to each axle its
share of the maximum loaded vehicle
weight and dividing it by two.
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 295).
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.
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.
356 Practical hints
What to do if …
Lamp in center console
ProblemPossible cause/consequenceSuggested solution
75
The indicator lamp illuminates and remains
illuminated with the weight of a typical adult
or someone larger than a small individual on
the front passenger seat.
The system is malfunctioning.Have the system checked as soon as
possible by an authorized
Mercedes-Benz Center.
Read and observe messages in the
multifunction display and follow cor-
rective steps (
page 358).
Warning!G
If the 75 indicator lamp
illuminates and remains illuminated with the
weight of a typical adult or someone larger
than a small individual on the front passen-
ger seat, do not have any passenger use the
front passenger seat until the system has
been repaired.
357 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
75
The indicator lamp does not illuminate
and/or does not remain illuminated
with the weight of a typical
12-month-old child in a standard child
restraint or less on the front passenger
seat.
The system is malfunctioning.Make sure that there is nothing between seat cush-
ion and child seat and check installation of the child
seat.
Make sure that no objects applying supplemental
weight onto the seat are present.
Make sure that no objects which apply forces to the
seat are present (e.g. objects such as books, brief-
cases etc. lodged behind or around the seat, head
restraints pushing against roof etc.). The system
may recognize such forces as supplemental weight.
If the light remains out, have the system checked as
soon as possible by an authorized Mercedes-Benz
Center. Do not transport a child on the front passen-
ger seat until the system has been repaired.
Read and observe messages in the multifunction
display and follow corrective steps (
page 358).
Warning!G
If the 75 indicator lamp does
not illuminate or remains out with the
weight of a typical 12-month-old child
in a standard child restraint or less on the
front passenger seat, do not transport a
child on the front passenger seat until the
system has been repaired.
364 Practical hints
What to do if …
Display messagePossible cause/conse-
quencePossible solution
Front Passenger
Airbag Enabled
See Operator’s ManualFront passenger front air bag is
activated while driving even
though a child, small individual,
or object below the system’s
weight threshold is on the front
passenger seat, or the front
passenger seat is empty. Ob-
jects on the seat or forces act-
ing on the seat may make the
system sense supplemental
weight.Stop the vehicle in a safe location as soon as possible and check the
front passenger seat for the following:
Apply the parking brake.
Switch off the ignition (page 38).
Open the front passenger door.
Remove child and child restraint from front passenger seat and
properly secure the child in rear seat employing the child restraint
if necessary.
Remove any other items from on and around the front passenger
seat and make sure the storage pocket on the back of the front pas-
senger seat is empty.
Make sure that no objects which apply forces to the seat are
present (e.g. objects such as books, briefcases etc. lodged behind
or around the seat, head restraints pushing against roof etc.). The
system may recognize such forces as supplemental weight and
sense that an occupant on the front passenger seat is of a greater
weight than actually present.
Keep the seat unoccupied, close the front passenger door and turn
on the ignition (
page 38).
(Continued on next page)
366 Practical hints
What to do if …
Display messagePossible cause/conse-
quencePossible solution
Front Passenger
Airbag Disabled
See Operator’s ManualFront passenger front air bag is
deactivated while driving even
though an adult or someone
larger than a small individual is
occupying the front passenger
seat. Forces acting on the seat
may make the system sense a
decrease in weight.Stop the vehicle in a safe location as soon as possible and check the
front passenger seat for the following:
Switch off the ignition (page 60).
Have the front passenger vacate the seat and exit the vehicle.
Adjust the seat in a height position (page 42).
Make sure that no objects which apply forces to the seat are
present (e.g. objects such as books, briefcases etc. lodged under-
neath, behind or around the seat). Such forces may cause the sys-
tem to sense that an occupant of a lesser weight than actually
present is on the front passenger seat.
Keep the seat unoccupied, close the front passenger door and turn
on the ignition (
page 38).
(Continued on next page)
418 Practical hints
Flat tire
Detach the electric air pump.
Stow electrical plug3 and air hose4
behind flap1 and place the air pump
back in the trunk.Lowering the vehicle
Lower vehicle by turning crank coun-
terclockwise until vehicle is resting ful-
ly on its own weight.
Remove the jack.
1-5 Wheel bolts
Tighten the five wheel bolts evenly, fol-
lowing the diagonal sequence illustrat-
ed (1 to 5), until all bolts are tight.
Observe a tightening torque of 96 lb-ft
(130 Nm).
Before storing the jack in the trunk, it
should be fully collapsed.
Warning!G
Follow recommend inflation pressures.
Do not overinflate tires. Overinflating tires
can result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes, etc.
Do not underinflate tires. Underinflated tires
wear unevenly, adversely affect handling
and fuel economy, and are more likely to fail
from being overheated.
iVehicles with Advanced TPMS*:
Do not activate the tire inflation pressure moni-
tor (
page 309) until a full size wheel/tire with
functioning sensor has been placed back into
service on the vehicle.
Warning!G
Have the tightening torque checked after
changing a wheel. The wheels could come
loose if they are not tightened to a torque of
96 lb-ft (130 Nm).
iWrap the damaged wheel in the protective
film that comes with the spare wheel and put the
wheel in the trunk.
You can also place the damaged wheel down into
the spare wheel well. In this case, you must stow
the luggage bowl in the trunk.