Page 249 of 288

such as axle or steering components.
Otherwise, the vehicle could be damaged.XStart the engine.XMake sure that the SmartKey is in position
2 in the ignition and that the engine is
running during the entire loading operation.XMove the transmission to N with the E-
SELECT lever. Check the transmission
position in the instrument cluster.
As soon as the vehicle is loaded:
XPrevent the vehicle from rolling away by
applying the electric parking brake.XShift the transmission to P with the button
in the center console.XTurn the SmartKey to position 0 in the
ignition lock and remove the SmartKey
from the ignition lock.XSecure the vehicle.
Fuses
Important safety notes
GWARNING
Only use fuses approved by Mercedes-Benz
with the specified amperage for the system in
question and do not attempt to repair or
bridge a blown fuse. Using other than
approved fuses or using repaired or bridged
fuses may cause an overload leading to a fire,
and/or cause damage to electrical
components and/or systems. Have the cause
determined and remedied by an authorized
Mercedes-Benz Center.
! Only use fuses that have been approved
for Mercedes-Benz vehicles and which
have the correct fuse rating for the system
concerned. Otherwise, components or
systems could be damaged.
The fuses in your vehicle serve to close down
faulty circuits. If a fuse blows, all the
components on the circuit and their functions
stop operating.
Blown fuses must be replaced with fuses of
the same rating, which you can recognize by
the color and value. The fuse ratings are listed
in the fuse allocation chart. An authorized
Mercedes-Benz Center will be happy to
advise you.
i If a fuse has blown, contact a breakdown
service or an authorized Mercedes-Benz
Center.
If the newly inserted fuse also blows, have the
cause traced and rectified at a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
Before changing a fuse
XPark the vehicle and apply the electric
parking brake.XSwitch off all electrical consumers.XRemove the SmartKey from the ignition
lock.
The fuses are located in various fuse boxes:
R fuse box in the footwell on the front-
passenger side
R fuse box in the rear
The "Relay and fuse information sheet" is
located with the wheel-change toolkit in the
trunk.
Fuse box in the footwell
Fuses247Breakdown assistanceZ
Page 250 of 288

XTo open: remove the carpet over the
footrest.XLoosen screws : on the floor panel using
a suitable tool.XRemove the floor panel.XTo close: install the floor panel again.XScrew in and tighten screws :.XPut in the carpet and press to secure.
!
The floor panel must be installed properly,
otherwise moisture or dirt could impair the
function of the fuses.
Fuse box in the rear
Coupe
XTo open: open the trunk.XFold cover : in the center of the rear wall
down in the direction of the arrow.XTo close: fold cover : up in the opposite
direction to the arrow and press to secure.
! The cover must be installed properly,
otherwise moisture or dirt could impair the
function of the fuses.
RoadsterXTo open: from the vehicle interior, lift up
cover : between the roll bars in the
direction of the arrow.XTo close: shut cover : in the opposite
direction to the arrow and press to secure.
! The cover must be installed properly,
otherwise moisture or dirt could impair the
function of the fuses.
248FusesBreakdown assistance
Page 251 of 288
Useful information ............................250
Important safety notes ....................250
Operation ........................................... 250
Winter operation ............................... 252
Tire pressure ..................................... 253
Loading the vehicle ..........................259
Maximum load rating .......................263
Uniform Tire Quality Grading
Standards .......................................... 263
Tire labeling ....................................... 265
Definition of terms for tires and
loading ............................................... 268
Changing a wheel ............................. 271
Wheel and tire combinations ...........272249Tires and wheels
Page 252 of 288

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 21).
Important safety notes
Consult an authorized Mercedes-Benz Center
if you require information on approved and
recommended tires and wheels for summer
and winter operation. Advice on purchasing
and caring for tires is also available there.
GWARNING
Replace rims or tires with the same
designation, manufacturer and type as shown
on the original part. For further information
contact an authorized Mercedes-Benz Center.
If incorrectly sized rims and tires are
mounted, the wheel brakes or suspension
components can be damaged. Also, the
operating clearance of the wheels and the
tires may no longer be correct.
GWARNING
Worn, old tires can cause accidents. If the tire
tread is worn to minimum tread depth, or if
the tires have sustained damage, replace
them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can result
in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or
recommended by Mercedes-Benz, since
previous damage cannot always be
recognized on retreads. The operating safety
of the vehicle cannot be assured when such
tires are used.GWARNING
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possible
damage to your vehicle has occurred, you
should turn on the hazard warning flashers,
carefully slow down, and drive with caution to
an area which is a safe distance from the road.
Inspect the tires and the vehicle underbody
for possible damage. If the vehicle appears
unsafe, have the vehicle towed to the nearest
authorized Mercedes-Benz Center or tire
dealer for repairs.
GWARNING
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
might lose control of the vehicle. Continued
driving with a flat tire or driving at high speed
with a flat tire will cause excessive heat build-
up and possibly a fire.
i Further information about tires and
wheels can be obtained from any
authorized Mercedes-Benz Center.
Operation
Notes on driving
R If the vehicle is heavily laden, check the tire
pressures and correct them if necessary.
R When parking your vehicle, make sure that
the tires do not get deformed by the curb
or other obstacles. If it is necessary to drive
over curbs, speed humps or similar
elevations, try to do so slowly and at an
obtuse angle. Otherwise, the tires,
particularly the sidewalls, can get
damaged.
250OperationTires and wheels
Page 253 of 288

Notes on regularly inspecting wheels
and tiresGWARNING
Regularly check the tires for damage.
Damaged tires can cause tire inflation
pressure loss. As a result, you could lose
control of your vehicle.
Worn, old tires can cause accidents. If the tire
tread is worn to minimum tread depth, or if
the tires have sustained damage, replace
them.
R Regularly check the wheels and tires of
your vehicle for damage (e.g. cuts,
punctures, tears, bulges on tires and
deformation or cracks or severe corrosion
on wheels) at least once a month, as well
as after driving off-road or on rough roads.
Damaged wheels can cause a loss of tire
pressure.
R Regularly check the tire tread depth and
the condition of the tread across the whole
width of the tire (Y page 251). If necessary,
turn the front wheels to full lock in order to
inspect the inner side of the tire surface.
R All wheels must have a valve cap to protect
the valve against dirt and moisture. Do not
mount anything onto the valve (such as tire
pressure monitoring systems) other than
the standard valve cap or other valve caps
approved by Mercedes-Benz for your
vehicle.
R Regularly check the pressure of all the tires
including the emergency spare wheel or the
spare wheel, particularly prior to long trips,
and correct the pressure as necessary
( Y page 253).
Tire tread
GWARNING
Although the applicable federal motor vehicle
safety laws consider a tire to be worn when
the tread wear indicators (TWI) become
visible at approximately 1
/ 16 in (1.6 mm), we
recommend that you do not allow your tires
to wear down to that level. As tread depth
approaches 1
/ 8 in (3 mm), the adhesion
properties on a wet road are sharply reduced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
Do not use tires that are excessively worn as
the tire traction on wet road surfaces
decreases significantly when the tread depth
is less than ⅛ inch (3 mm).
Tread wear indicators (TWI) are required by
law. Six indicators are positioned on the tire
tread. They become visible as soon as a tread
depth of approximately 1
/ 16 inch (1.6 mm)
has been reached. If this is the case, the tire
is so worn that it must be replaced.
The recommended tread depth for summer
tires is at least ⅛ inch (3 mm). The
recommended tread depth for winter tires is
at least 1
/ 6 inch (4 mm).
Bar marking
: for tread wear is integrated
into the tire tread.
Notes on selecting, mounting and
replacing tires
R Only mount tires and wheels of the same
type and make.
R Only mount tires of the correct size onto
the wheels.
R After mounting new tires, run them in at
moderate speeds for the first 60 miles
Operation251Tires and wheelsZ
Page 254 of 288

(100 km) as they only reach their full
performance after this distance.
R Do not use tires that are excessively worn
as the tire traction on wet road surfaces
decreases significantly when the tread
depth is less than 1
/ 8 inch (3 mm).
R Replace the tires after six years at the
latest, regardless of wear. This also applies
to the spare wheel/emergency spare
wheel.
The service life of tires depends on the
following factors amongst other things:
R driving style
R tire pressure
R mileage
Winter operation
General notes
Have your vehicle winterproofed at a qualified
specialist workshop at the onset of winter.
Observe the notes in the "Changing a wheel"
section ( Y page 271).
Driving with summer tires
At temperatures below 45 ‡ (+7 †), the
elasticity of summer tires and therefore also
the traction and braking capability are
reduced considerably — equip your vehicle
with M+S tires. Using summer tires at very
cold temperatures could cause tears to form,
thereby damaging the tires permanently.
Mercedes-Benz cannot accept responsibility
for this type of damage.
Snow chains
! There is not enough space for snow
chains on some wheel sizes. Observe the
information under "Tires and wheels" in the
"Technical Data" section to avoid damage
to the vehicle or the wheels.
For safety reasons, Mercedes-Benz
recommends that you only use snow chains
that have been specially approved for your
vehicle by Mercedes-Benz, or are of a
corresponding standard of quality.
R local regulations may restrict the use of
snow chains. Observe the appropriate
regulations if you wish to mount snow
chains.
R only use snow chains when driving on roads
completely covered by snow. Remove the
snow chains as soon as possible when you
come to a road that is not snow-covered.
R Do not exceed the maximum permissible
speed of 30 mph (50 km/h).
R you may not mount snow chains to all
wheel-tire combinations; see the
information under "Wheels and tires" in the
"Technical data" section.
R snow chains must not be mounted on
emergency spare wheels.
R mount snow chains only in pairs and only
on the rear wheels. Observe the
manufacturer's installation instructions.
! If snow chains are mounted on the front
wheels, the snow chains could grind
against the bodywork or components of the
chassis. This could result in damage to the
vehicle or the tires.
i You may wish to deactivate
ESP ®
(Y page 56) when pulling away with
snow chains mounted. This way you can
allow the wheels to spin in a controlled
manner, achieving an increased driving
force (cutting action).
M+S tires
GWARNING
M+S tires with a tread depth of less than 1
/ 6
inch (4 mm) must be replaced. They are no
longer suitable for winter operation.
252Winter operationTires and wheels
Page 255 of 288

GWARNING
If you mount the spare wheel when driving
with M+S tires, bear in mind that driving
stability will be impaired due to unstable
cornering characteristics caused by the
different tire characteristics. Adapt your style
of driving accordingly.
Have the spare wheel replaced by a normal
wheel with an M+S tire at the nearest
Mercedes-Benz Center.
At temperatures below 45 ‡(+7 †), use
winter tires or all-season tires. Both types of
tire are identified by the M+S marking.
Only winter tires bearing the i snowflake
symbol in addition to the M+S marking
provide the best possible grip in wintry road
conditions. Only these tires will allow driving
safety systems such as ABS and ESP ®
to
function optimally in winter, as these tires
have been designed specifically for driving on
snow.
Use M+S tires of the same make and tread on
all wheels to maintain safe handling
characteristics.
Always observe the maximum permissible
speed specified for the M+S tires you have
mounted.
When you have installed the M+S tires:
XCheck the tire pressures ( Y page 253).XRestart the tire pressure monitor
( Y page 259).
Tire pressure
Tire pressure specifications
GWARNING
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver's door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
You will find a table of recommended tire
pressures on the Tire and Loading
Information placard on the B-pillar on the
driver's side ( Y page 259). You will find a
table of tire pressures for various operating
conditions on the inside of your vehicle's fuel
filler flap.
To test tire pressure, use a suitable pressure
gauge. The outer appearance of a tire does
not permit any reliable conclusion about the
tire pressure. On vehicles equipped with the
electronic tire pressure monitoring system,
the tire pressure can be checked using the
on-board computer.GWARNING
Should the tire pressure drop repeatedly:
R check the tire for foreign bodies.
R check whether the wheel is losing air or the
valve is leaking.
R make sure that only a valve cap approved
by Mercedes-Benz is installed on the tire
valve.
Tire pressures that are too low have a
negative effect on vehicle safety, which could
lead you to cause an accident.
Only correct tire pressures when the tires are
cold. The tires are cold when the vehicle has
been parked for at least three hours or driven
for less than 1 mile (1.6 km). The tire
temperature changes depending on the
outside temperature, the vehicle speed and
Tire pressure253Tires and wheelsZ
Page 256 of 288

the tire load. If the tire temperature changes
by 18 ‡ (10 † ), the tire pressure changes
by approximately 10 kPa (0.1 bar/1.5 psi).
Take this into account when checking the
pressure of warm tires and only correct the
tire pressure if it is too low for the current
operating conditions. If you check the tire
pressure when the tires are warm, the
resulting value will be higher than if the tires
were cold. This is normal. Do not reduce the
tire pressure to the value specified for cold
tires. The tire pressure would otherwise be
too low.
Observe the recommended tire pressure
specifications for cold tires on the Tire and
Loading Information placard on the B-pillar on
the driver's side.
i The specifications given on the following
Tire and Loading Information placard are
examples. Tire pressure specifications are
vehicle-specific and may deviate from the
data shown here. The tire pressures
applicable to your vehicle can be found on
the Tire and Loading Information placard on
your vehicle.
You will find recommended tire pressure
specifications : for cold tires and for a fully
loaded vehicle on the Tire and Loading
Information placard. The tire pressure
information is applicable to all tires mounted
at the factory.
Important notes on tire pressureGWARNING
If the tire pressure drops repeatedly, check
the tires for punctures from foreign objects
and/or whether air is leaking from the valves
or from around the rim.
The tire temperature and pressure increase
when the vehicle is in motion. This is
dependent on the driving speed and the load.
If you wish to drive at high speeds of
100 mph (160 km/h) or higher when this is
allowed, use the tire pressure table on the
inside of the fuel filler flap to set the correct
tire pressures when the wheels are cold. If the
tire pressure is not set correctly, this can lead
to an excessive build-up of heat and a sudden
loss of pressure.
For more information, contact a qualified
specialist workshop.
i Driving comfort can be impaired if the tire
pressure value recommended in the tire
pressure table for speeds over
100 mph(160 km/h) is adopted.
Make sure that the tire pressure for normal
speeds is adopted again.
Additional specifications of tire pressure
values for loads can also be found on the tire
pressure table on the inside of the fuel filler
flap.
i Specifications shown in the examples of
tire pressure tables are for illustration
purposes only. Tire pressure specifications
are vehicle-specific and may deviate from
the data shown here. Tire pressure
specifications applicable to your vehicle
are located in your vehicle's tire pressure
table.
Unless stated otherwise, the tire pressures
specified on the fuel filler flap apply to all tires
approved for this vehicle.
254Tire pressureTires and wheels