winter tires MERCEDES-BENZ S-Class 2012 W221 Owner's Manual

WindshieldDefrosting ...................................... 296
Infrared reflective .......................... 454
Windshield washer system .............. 461
Notes ............................................. 529
Windshield wipers
Problem (malfunction) ...................286
Replacing the wiper blades ............285
Switching on/off ........................... 285
Winter driving
Important safety notes ..................492
Slippery road surfaces ...................330
Snow chains .................................. 493
Winter operation
Radiator cover ............................... 457
Winter tires
M+S tires ....................................... 492
Wiper blades
Cleaning ......................................... 466
Important safety notes ..................285
Wooden trim (cleaning
instructions) ...................................... 468Index27

RADAPTIVE BRAKE
R PRE-SAFE ®
Brake
Important safety notes
GWARNING
The following factors increase the risk of
accidents:
R Excessive speed, especially in turns
R Wet and slippery road surfaces
R Following another vehicle too closely
The driving safety systems described in this
section cannot reduce these risks or prevent
the natural laws of physics from acting on the
vehicle. They cannot increase braking or
steering efficiency beyond that afforded by
the condition of the vehicle brakes and tires
or the traction afforded.
Only a safe, attentive, and skillful driver can
prevent accidents.
The capabilities of a vehicle equipped with the
driving safety systems described in this
section must never be exploited in a reckless
or dangerous manner which could jeopardize
the user's safety or the safety of others.
Always adjust your driving style to the
prevailing road and weather conditions and
keep a safe distance to other road users and
objects on the street.
If a driving system malfunctions, other driving
safety systems may also switch off. Observe
indicator and warning lamps that may come
on as well as messages in the multifunction
display that may appear.
GWARNING
HYBRID vehicles: It is imperative that you read
the HYBRID Supplemental Operating
Instructions included in your vehicle literature
portfolio. You may otherwise not receive all
necessary safety information and warning for
the operation of your vehicle.
i Please note that the driving safety
systems described only work as effectively
as possible when there is adequate contact
between the tires and the road surface. Pay
particular attention to the information
regarding tires, recommended minimum
tire tread depths etc. in the "Wheels and
tires" section ( Y page 490).
In wintry driving conditions, always use
winter tires (M+S tires) and if necessary,
snow chains. Only in this way will the
driving safety systems described in this
section work as effectively as possible.
ABS (Anti-lock Braking System)
Important safety notes
i Observe the "Important safety notes"
section ( Y page 69).
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the
vehicle when braking.
ABS works from a speed of about
5 mph(8 km/h) upwards, regardless of road-
surface conditions. ABS works on slippery
surfaces, even when you only brake gently.
GWARNING
If the ABS malfunctions, other driving systems
such as the BAS or the ESP ®
are also switched
off. Observe indicator and warning lamps that
may come on as well as messages in the
multifunction display that may appear.
If the ABS malfunctions, the wheels may lock
during hard braking, reducing the steering
capability and extending the braking distance.
The ! warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
Braking
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
Driving safety systems69SafetyZ

by the engine's air suction nozzles and this
can cause engine damage.
Winter driving
General notes
GWARNING
If the vehicle becomes trapped in snow,
ensure that snow is kept away from the
exhaust pipe and from around the vehicle as
long as the engine is running. Otherwise,
poisonous carbon monoxide (CO) may enter
the vehicle, resulting in loss of consciousness
and even death.
To assure sufficient fresh air ventilation, open
a window slightly on the side of the vehicle
not facing the wind.
At the onset of winter, have your vehicle
winterproofed at a qualified specialist
workshop, e.g. at an authorized Mercedes-
Benz Center.
Observe the notes in the "Winter operation"
section ( Y page 492).
Driving with summer tires
Observe the notes in the "Winter operation"
section ( Y page 492).
Slippery road surfaces
GWARNING
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Indicated temperatures just above the
freezing point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges.
GWARNING
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle
control. Your vehicle's ABS will not prevent
this type of loss of control.
Drive particularly carefully on slippery road
surfaces. Avoid sudden acceleration, steering
and braking maneuvers. Do not use cruise
control or DISTRONIC PLUS.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:XShift the transmission to position N.
i
For more information on driving with
snow chains, see ( Y page 493).
GWARNING
Make sure that you do not endanger other
road users when you apply the brakes.
Driving systems
Cruise control
Important safety notes
Cruise control maintains a constant road
speed for you. It brakes automatically in order
to avoid exceeding the set speed. On long and
steep downhill gradients, especially if the
vehicle is laden, you must select shift range
1 , 2 or 3 in good time. By doing so, you will
make use of the braking effect of the engine,
which relieves the load on the brake system
and prevents the brakes from overheating
and wearing too quickly.
Use cruise control only if road and traffic
conditions make it appropriate to maintain a
steady speed for a prolonged period. You can
set any road speed above 20 mph
(30 km/h).
GWARNING
The cruise control is a convenience system
designed to assist the driver during vehicle
operation. The driver is and must always
remain responsible for the vehicle's speed
and for safe brake operation.
330Driving systemsDriving and parking

Suspension tuning
The electronically controlled ABC suspension
system works continuously. This improves
driving safety and comfort.
The ABC suspension system is tuned
individually to each wheel and depends on:
R your driving style, e.g. sporty
R the road surface condition, e.g. bumps
R your individual selection, i.e. sports or
comfort
R the vehicle load
Your selection remains stored even if you
remove the SmartKey from the ignition lock.
Sports tuning
The firmer suspension tuning in Sport mode
ensures even better contact with the road.
Select this mode if you prefer a firmer
suspension tuning.
XIf indicator lamp ; is not lit: press
button :.
Indicator lamp ; lights up. You have
selected the suspension for a sporty driving
style.
The ABC Active Body Control SPORT
message appears in the multifunction
display.
Comfort tuning
In Comfort mode, the driving characteristics
of your vehicle are more comfortable. Select
this mode if you prefer a more comfortable
driving style.
XIf indicator lamp ; is lit: press
button :.
Indicator lamp ; goes out. You have
selected the suspension for a comfortable
driving style.
The ABC Active Body Control
COMFORT message appears in the
multifunction display.
4MATIC (permanent four-wheel drive)
4MATIC ensures that all four wheels are
permanently driven. Together with ESP ®
, it
improves the traction of your vehicle
whenever a drive wheel spins due to
insufficient grip.
GWARNING
If a drive wheel is spinning due to insufficient
traction:
R While driving off, apply as little throttle as
possible.
R While driving, ease up on the accelerator
pedal.
R Adapt your speed and driving style to the
prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid.
The 4MATIC cannot prevent accidents
resulting from excessive speed.
! Never tow the vehicle with one axle
raised. This may damage the transfer case.
Damage of this sort is not covered by the
Mercedes-Benz Limited Warranty. All
wheels must remain either on the ground
or be fully raised. Observe the instructions
for towing the vehicle with all wheels in full
contact with the ground.
i In wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if
you use winter tires ( M+S tires), with snow
chains if necessary.
346Driving systemsDriving and parking

RVehicles with a SmartKey:
Do not remove the SmartKey from the
ignition lock. Do not open the driver's
door or front-passenger door when the
engine is switched off. Otherwise, the
automatic transmission selects park
position P automatically and locks the
wheels. You can prevent this by shifting
the automatic transmission to N
beforehand.
R Vehicles with KEYLESS-GO:
Do not open the driver's door or front-
passenger door when the engine is
switched off. Otherwise, the automatic
transmission selects park position P
automatically and locks the wheels.
Observe the following to make sure that the
automatic transmission stays in position N:XMake sure the vehicle is stationary and the
ignition is switched off.XTurn the SmartKey to position
2 (Y page 303) in the ignition lock.
Use the SmartKey instead of the Start/
Stop button on vehicles with KEYLESS-GO.XDepress and hold the brake pedal.XShift the automatic transmission to
position N.XRelease the brake pedal.XRelease the electric parking brake.XSwitch off the ignition and leave the
SmartKey in the ignition lock.
! Make sure that:
R the side windows and the sliding sunroof
are fully closed.
R the ventilation/heating is switched off
(the OFF button has been pressed).
R the windshield wiper switch is in position
0 .
Otherwise, the vehicle might be damaged.
After using an automatic car wash, wipe off
wax from the windshield and the wiper
blades. This will prevent smears and reduce
wiping noises caused by residue on the
windshield.
Washing by hand
Carefully remove all deposits of road salt as
soon as possible when driving in winter.
Also, clean the insides of the wheels when
washing the underbody of the vehicle.
XDo not use hot water and do not wash the
vehicle in direct sunlight.XUse a soft car sponge for cleaning.XUse a gentle cleaning agent, e.g. a
Mercedes-Benz approved car shampoo.XWash down the vehicle with a gentle water
jet.XDo not point the water jet directly at the air
inlets.XUse plenty of water and rinse the sponge
frequently.XRinse the vehicle with clean water and dry
it thoroughly with a chamois.XDo not allow the cleaning agent to dry on
the paintwork.
Power washers
GWARNING
Do not use power washers with circular-jet
nozzles (dirt grinders) to clean your vehicle, in
particular the tires. You could otherwise
damage the tires and cause an accident.
! Always maintain a distance of at least
11.8 in (30 cm) between the vehicle and the
power washer nozzle. Information about
the correct distance is available from the
equipment manufacturer.
Move the power washer nozzle around
when cleaning your vehicle.
Do not aim directly at any of the following:
R tires
R door gaps, roof gaps, joints etc.
R electrical components
R battery
R connectors
R lights
R seals
464CareMaintenance and care

Useful information ............................490
Important safety notes ....................490
Operation ........................................... 490
Winter operation ............................... 492
Tire pressure ..................................... 493
Loading the vehicle ..........................500
Maximum load rating .......................504
Uniform Tire Quality Grading
Standards .......................................... 505
Tire labeling ....................................... 506
Definition of terms for tires and
loading ............................................... 510
Changing a wheel ............................. 513
Wheel and tire combinations ...........514489Wheels and tires

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 31).
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.
490OperationWheels and tires

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 491). 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 493).
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 1
/ 8 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 1
/ 8 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
Operation491Wheels and tiresZ

(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
MOExtended tires (tires with run-flat
properties)
MOExtended tires (tires with run-flat
properties) allow you to continue driving your
vehicle even if one or more tires are entirely
deflated.
MOExtended tires may be used only in
conjunction with the activated tire pressure
loss warning system or the activated tire
pressure monitoring system and only on
wheels specifically tested by Mercedes-Benz.
You will find notes on driving with
MOExtended tires in the "Breakdown
assistance" section ( Y page 477).
Winter operation
Please bear the following in mind
At the onset of winter, have your vehicle
winterproofed at a qualified specialist
workshop, e.g. at an authorized Mercedes-
Benz Center.
Observe the notes in the "Changing a wheel"
section ( Y page 513).
Driving with summer tires
At temperatures below 45 ‡ (+7 †), the
elasticity of summer tires and therefore also
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.
M+S tires
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.
GWARNING
M+S tires with a tread depth of less than 1
/ 6
inch (4 mm) must be replaced immediately.
They are no longer suitable for use in winter.
Always observe the maximum permissible
speed specified for the M+S tires you have
mounted.
Once you have mounted the winter tires:
XCheck the tire pressures ( Y page 497).XRestart the tire pressure monitor
( Y page 497).GWARNING
If you use your spare wheel when M+S tires
are mounted on the other wheels, be aware
that the difference in tire characteristics
492Winter operationWheels and tires

the tire's ability to stop on a wet surface as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete. A tire marked C may have poor
traction performance.GWARNING
If ice has formed on the road, tire traction will
be substantially reduced. Under such weather
conditions, drive, steer and brake with
extreme caution.
The safe speed on a wet, snow covered or icy
road is always lower than on dry road
surfaces.
You should pay special attention to road
conditions when temperatures are around
the freezing point.
Mercedes-Benz recommends a minimum tire
tread depth of 1
/ 6 in (4 mm) for all four winter
tires ( Y page 492) to maintain normal driving
characteristics in winter. Winter tires can
reduce the braking distance on snow covered
surfaces in comparison to summer tires.
Stopping distance, however, is still
considerably greater than when the road is
not covered with ice or snow. Take
appropriate care when driving.
! Avoid wheelspin. This can lead to damage
to the drive train.
Temperature
GWARNING
The temperature grade for this tire is
established for a tire that is properly inflated
and not overloaded. Excessive speed,
underinflation, or excessive loading, either
separately or in combination, can cause
excessive heat build-up and possible tire
failure.
The temperature grades are A (the highest),
B, and C. These represent the tire's
resistance to the generation of heat and its
ability to dissipate heat when tested under
controlled conditions on a specified indoor
laboratory test wheel. Sustained high
temperature can cause the material of the tire
to degenerate and reduce tire life, and
excessive temperature can lead to sudden
tire failure. The grade C corresponds to a level
of performance which all passenger car tires
must meet under the Federal Motor Vehicle
Safety Standard No. 109. Grades B and A
represent higher levels of performance on the
laboratory test wheel than the minimum
required by law.
Tire labeling
Tire labeling overview
The following markings are on the tire in
addition to the tire name (sales designation)
and the manufacturer's name:
:Uniform tire Quality Grading Standard
( Y page 511);DOT, Tire Identification Number
( Y page 509)=Maximum tire load ( Y page 504)?Maximum tire pressure ( Y page 496)AManufacturerBTire material ( Y page 510)506Tire labelingWheels and tires