331 Operation
Tires and wheels
Tire 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 three 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 GWV must never exceed the
GWVR indicated on the certification label
located on the driver’s door B-pillar.
332 Operation
Tires and wheels
GVWR (Gross 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
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,
total load limit 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 (Pounds per square inch)
A standard unit of measure for air pressure
-> bar, kilopascal (kPa).
Recommended tire inflation pressure
The recommended tire inflation pressure
for normal driving conditions is listed on
the Tire and Loading Information placard
located on the driver’s door B-pillar and
provides best handling, tread life and
riding comfort. If so equipped, supplemen-
tal information 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.
334 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 307).
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 3 000 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 307).
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 discs, 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 392) and
(
page 408).
Warning!G
Rotate front and rear wheels only if the tires
are of the same dimension.
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
80 lb-ft (110 Nm).
Only use genuine Mercedes-Benz wheel
bolts specified for your vehicle’s rims.
340 Operation
Vehicle care
Cleaning and care of vehicle
Regular and proper care will help to main-
tain the value of your vehicle. The best way
to protect your vehicle from harmful envi-
ronmental influences is to wash it and use
protective treatments regularly.
While in operation, even while parked, your
vehicle is subjected to varying external in-
fluences which, if gone unchecked, can at-
tack the paintwork as well as the
undercarriage and cause lasting damage.Such damage is caused not only by
extreme and varying climatic conditions,
but also by:
Air pollution
Road salt
Tar
Gravel and stone chipping
To avoid paint damage, you should imme-
diately remove:
Grease and oil
Fuel
Coolant
Brake fluid
Bird droppings
Insects
Tree resins, etc.
Frequent washing reduces and/or elimi-
nates the aggressiveness and potency of
the above adverse influences.More frequent washings are necessary to
deal with unfavorable conditions:
near the ocean
in industrial areas (smoke, exhaust
emissions)
during winter operation
You should check your vehicle from time to
time for stone chipping or other damage.
Any damage should be repaired as soon as
possible to prevent corrosion.
In doing so, do not neglect the underbody
of the vehicle. A prerequisite for a
thorough check is a washing of the under-
body followed by a thorough inspection.
Damaged areas need to be
re-undercoated.
Your vehicle has been treated at the
factory with a wax-base rustproofing in the
body cavities which will last for the lifetime
of the vehicle. Post-production treatment
is neither necessary nor recommended by
Mercedes-Benz because of the possibility
Warning!G
Many cleaning products can be hazardous.
Some are poisonous, others are flammable.
Always follow the instructions on the partic-
ular container. Always open your vehicle’s
doors or windows when cleaning the inside.
Never use fluids or solvents that are not de-
signed for cleaning your vehicle.
Always lock away cleaning products and
keep them out of reach of children.
344 Operation
Vehicle care
Fold the wiper arms forward until they
snap into place.
Clean the wiper blade inserts with a
clean cloth and detergent solution.
Use a clean cloth and a mild window
cleaning solution on all outside and
inside glass surfaces.
An automotive glass cleaner is recom-
mended.Rear window cleaning
Clean the rear window with the hardtop
fully raised and closed.
Use a clean cloth and a mild window
cleaning solution on all outside and
inside glass surfaces.
An automotive glass cleaner is recom-
mended.Light alloy wheels
If possible, clean wheels once a week.
Use Mercedes-Benz approved Wheel
Care, a soft bristle brush and a strong
spray of water for cleaning the light al-
loy wheels.!Do not pull on the wiper blade inserts. They
could tear.
!Fold the windshield wiper arms back onto
the windshield before turning the SmartKey in
the starter switch.
Hold on to the wiper when folding the wiper arm
back. If released, the force of the impact from
the tensioning spring could crack the windshield.
!To clean the window interior, do not use a
dry cloth, abrasives, solvents or cleaners con-
taining solvents. Do not touch the inside of the
front, rear or side windows with hard objects
such as an ice scraper or ring. Doing so may
damage the windows.
Warning!G
Do not clean the rear window with the hard-
top in a position other than the fully raised
and closed position. Otherwise, the hardtop
may move unexpectedly which may result in
personal injury to you or others.!Only use acid-free cleaning materials. Acid
may cause corrosion or damage the clear coat.
!The vehicle should not be parked for an
extended period of time immediately after it has
been cleaned, especially not after the wheel rims
have been cleaned with wheel rim cleaner.
Wheel rim cleaners can lead to increased corro-
sion of the brake discs and brake pads.
Non-approved wheel cleaners may also damage
the wheel paint if the car is not driven after
cleaning. Therefore, the vehicle’s brake system
should always be warmed-up before it is parked
after cleaning. To do so, please drive your vehicle
for several minutes to allow the brakes to dry.
When applying Mercedes-Benz approved Tire
Care and Mercedes-Benz approved Wheel Care
products, take care not to spray them on the
brake discs.
348 Practical hints
What to do if …
Lamps in instrument clusterGeneral information:
If any of the following lamps in the instru-
ment cluster fails to come on during thebulb self-check when switching on ignition
(
page 37), have the respective bulb
checked and replaced if necessary.
ProblemPossible cause/consequenceSuggested solution
-The yellow ABS indicator lamp comes on
when the engine is running.The ABS has detected a malfunction
and has switched off. The BAS and
ESP
® are also switched off (see mes-
sages in the multifunction display).
The brake system is still functioning
normally but without the systems
specified above.
If the ABS control unit is malfunction-
ing, other systems such as the naviga-
tion system* or the automatic
transmission* may also be malfunc-
tioning.
Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability.
Read and observe messages in the
multifunction display (
page 360).
Have the system checked at an
authorized Mercedes-Benz Center as
soon as possible.
Failure to follow these instructions in-
creases the risk of an accident.
The charging voltage has fallen below
10 volts. The ABS has switched off.
The battery might not be charged suf-
ficiently.When the voltage is above this value
again, the ABS is operational again an the
ABS indicator lamp should go out.
If the ABS indicator lamp does not go out:
Have the generator (alternator) and
battery checked.
349 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
-The yellow ABS indicator lamp comes on
when the engine is running.The ABS is temporary not available.
The ESP® and the BAS are also un-
available.
The system’s self-diagnosis may not
be completed yet.
The brake system is still functioning
normally but without the systems
specified above.
Drive a short distance with added
caution at a vehicle speed of above
12 mph (20 km/h).
When the ABS indicator lamp goes
out, the ABS, the ESP
®, and the BAS
are available again.
If the yellow ABS indicator lamp does not
go out:
Continue driving with added caution.
Have the system checked at an
authorized Mercedes-Benz Center as
soon as possible.
Failure to follow these instructions
increases the risk of an accident.
350 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
USA only:
;
Canada only:
3
The red brake warning lamp
comes on when the engine is
running and an acoustic warning
sounds.You are driving with the parking brake
set.Release the parking brake (page 53).
The red brake warning lamp
comes on when the engine is
running.There is insufficient brake fluid in the
reservoir.Risk of accident!
Carefully stop the vehicle in a safe loca-
tion or as soon as it is safe to do so.
Apply the parking brake (page 59).
Read and observe messages in the dis-
play (
page 360).
Contact an authorized Mercedes-Benz
Center.
Do not add brake fluid! This will not solve
the problem.
Warning!G
Driving with the brake warning lamp illumi-
nated can result in an accident. Have your
brake system checked immediately if the
brake warning lamp stays on.
Do not add brake fluid before checking the
brake system. Overfilling the brake fluid
reservoir can result in spilling brake fluid on
hot engine parts and the brake fluid catch-
ing fire. You can be seriously burned.!If you find that the brake fluid in the brake
fluid reservoir has fallen to the minimum mark or
below, have the brake system checked for brake
pad thickness and leaks.