2015 MERCEDES-BENZ S-Class COUPE ECU

Underinflated or overinflated tires
Underinflated tires G
WARNING
Tires with pressure that is too low can over-
heat and burst as a consequence. In addition, they also suffer from excessive and/or irreg-
ular wear, which can severely impair the brak- ing properties and the driving characteristics.There is a risk of an accident.
Avoid tire pressures that are too low in all the
tires, including the spare wheel.
Underinflated tires may:
R overheat, leading to tire defects
R adversely affect handling
R wear excessively and/or unevenly
R have an adverse effect on fuel consumption
Overinflated tires G
WARNING
Tires with excessively high pressure can burst
because they are damaged more easily by
road debris, potholes etc. In addition, they
also suffer from irregular wear, which can
severely impair the braking properties and the driving characteristics. There is a risk of an
accident.
Avoid tire pressures that are too high in all the
tires, including the spare wheel.
Overinflated tires may: R increase the braking distance
R adversely affect handling
R wear excessively and/or unevenly
R have an adverse effect on ride comfort
R be more susceptible to damage Maximum tire pressures 0043
Example: maximum permissible tire pres-
sure
Never exceed the maximum permissible tire
inflation pressure. Always observe the rec-
ommended tire pressure for your vehicle
when adjusting the tire pressure
(Y page 359).
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration. Checking the tire pressures
Important safety notes Observe the notes on tire pressure
(Y
page 359).
Information on air pressure for the tires on
your vehicle can be found:
R on the vehicle's Tire and Loading Informa-
tion placard on the B-pillar
R on the tire pressure label on the fuel filler
flap
R in the "Tire pressure" section
Checking tire pressures manually To determine and set the correct tire pres-
sure, proceed as follows:
X Remove the valve cap of the tire that is to
be checked.
X Press the tire pressure gauge securely onto
the valve. 362
Tire pressureWheels and tires

Tread
The part of the tire that comes into contact
with the road.
Bead
The tire bead ensures that the tire sits
securely on the wheel. There are several steel
wires in the bead to prevent the tire from
coming loose from the wheel rim.
Sidewall
The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras that weigh more than the replaced standard
parts and more than 5 lbs (2.3 kg). These
optional extras, such as high-performance
brakes, level control, a roof rack or a high-
performance battery, are not included in the
curb weight and the weight of the accesso-
ries.
TIN (Tire Identification Number)
This is a unique identifier which can be used
by a tire manufacturer to identify tires, for
example for a product recall, and thus identifythe purchasers. The TIN is made up of the
manufacturer's identity code, tire size, tire
type code and the manufacturing date.
Load bearing index
The load bearing index (also load index) is a
code that contains the maximum load bearing capacity of a tire.
Traction
Traction is the result of friction between the
tires and the road surface.
Treadwear indicators
Narrow bars (tread wear bars) that are dis-
tributed over the tire tread. If the tire tread is level with the bars, the wear limit of 00CDin
(1.6 mm) has been reached. Occupant distribution
The distribution of occupants in a vehicle at
their designated seating positions.
Total load limit
Nominal load and luggage load plus 68 kg
(150 lbs) multiplied by the number of seats in
the vehicle. Changing a wheel
Flat tire
The "Breakdown assistance" section
(Y page 336 )contains information and notes
on how to deal with a flat tire. Information on
driving with MOExtended tires in the event of
a flat tire can be found under "MOExtended
tires (tires with run-flat characteristics"
(Y page 337). Rotating the wheels
G
WARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics if
the wheels or tires have different dimensions. The wheel brakes or suspension components
may also be damaged. There is a risk of acci-
dent.
Rotate front and rear wheels only if the wheels and tires are of the same dimensions.
! On vehicles equipped with a tire pressure
monitor, electronic components are loca-
ted in the wheel.
Tire-mounting tools should not be used
near the valve. This could damage the elec- tronic components.
Only have tires changed at a qualified spe-cialist workshop.
Always observe the instructions and safety
notes in the "Mounting a wheel" section
(Y page 378).
The wear patterns on the front and rear tires
differ, depending on the operating conditions. Changing a wheel
377Wheels and tires Z

Rotate the wheels before a clear wear pattern
has formed on the tires. Front tires typically
wear more on the shoulders and the rear tires in the center.
If your vehicle's tire configuration allows, you
can rotate the wheels according to the inter-
vals in the tire manufacturer's warranty book in your vehicle documents. If no warranty
book is available, the tires should be rotated
every 3,000 to 6,000 miles (5,000 to
10,000 km), or earlier if tire wear requires.
Ensure the direction of rotation is maintained.
Clean the contact surfaces of the wheel and
the brake disc thoroughly every time a wheel
is rotated. Check the tire pressure and reac-
tivate the tire pressure monitor if necessary
(Y page 365). Direction of rotation
Tires with a specified direction of rotation
have additional benefits, e.g. if there is a risk of hydroplaning. These advantages can only
be gained if the tires are installed correspond- ing to the direction of rotation.
An arrow on the sidewall of the tire indicates
its correct direction of rotation. Storing wheels
Store wheels that are not being used in a cool, dry and preferably dark place. Protect the
tires from oil, grease, gasoline and diesel. Mounting a wheel
Preparing the vehicle X
Stop the vehicle on solid, non-slippery and
level ground.
X Apply the electric parking brake manually.
X Bring the front wheels into the straight-
ahead position.
X Shift the transmission to position P.X
Make sure that "normal" level is selected
for AIRMATIC (Y page 192).
X Switch off the engine.
X Open the driver's door.
The on-board electronics now have status
0. This is the same as the SmartKey having
been removed.
X Remove Start/Stop button from ignition
lock (Y page 147).
or, if the SmartKey is inserted in the ignition
lock: X Remove the SmartKey from the ignition
lock.
X If included in the vehicle equipment,
remove the tire-change tool kit from the
vehicle.
X Secure the vehicle to prevent it from rolling
away.
Securing the vehicle to prevent it from
rolling away If your vehicle is equipped with a wheel chock,
it can be found in the tire-change tool kit
(Y page 336).
The folding wheel chock is an additional
safety measure to prevent the vehicle from
rolling away, for example when changing a
wheel.
X Fold both plates upwards 0043.
X Fold out lower plate 0044.
X Guide the lugs on the lower plate fully into
the openings in base plate 0087.378
Changing a wheelWheels and
tires

X
On level ground: place chocks or other
suitable items under the front and rear of
the wheel that is diagonally opposite the
wheel you wish to change. X
On light downhill gradients: place
chocks or other suitable items in front of
the wheels of the front and rear axle.
Raising the vehicle G
WARNING
If you do not position the jack correctly at the appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle.
! The jack is designed exclusively for jack-
ing up the vehicle at the jacking points.
Otherwise, your vehicle could be damaged. Observe the following when raising the
vehicle:
R To raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If used incor-
rectly, the jack could tip over with the vehi- cle raised.
R The jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suited for per-
forming maintenance work under the vehi- cle.
R Avoid changing the wheel on uphill and
downhill slopes.
R Before raising the vehicle, secure it from
rolling away by applying the parking brake
and inserting wheel chocks. Do not disen-
gage the parking brake while the vehicle is
raised.
R The jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, flat, load-bearing underlay must be
used. On a slippery surface, a non-slip
underlay must be used, e.g. rubber mats.
R Do not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacity due to the restricted
height.
R Make sure that the distance between the
underside of the tires and the ground does
not exceed 1.2 in (3 cm).
R Never place your hands and feet under the
raised vehicle.
R Do not lie under the vehicle.
R Do not start the engine when the vehicle is
raised.
R Do not open or close a door or the trunk lid
when the vehicle is raised.
R Make sure that no persons are present in
the vehicle when the vehicle is raised.
Vehicles with AMG wheels and hub caps:
the hub cap covers the wheel bolts. Before
you can unscrew the wheel bolts, you must Changing a wheel
379Wheels and tires Z

remove the hub cap. Two different variants
can be installed. Vehicles with AMG wheels and plastic
hub caps:
X To remove: turn the center cover of hub
cap 0043counter-clockwise and remove.
X To install: before installing, ensure that
hub cap 0043is in the open position. To do so,
turn the center cover counter-clockwise.
X Put hub cap 0043in position and turn the
center cover clockwise until you feel and
hear hub cap 0043engage.
X Make sure that hub cap 0043is installed
securely. Vehicles with AMG wheels and aluminum
hub caps:
X To remove: take socket0044and lug wrench
0087 from the vehicle tool kit (Y page 336).
X Position socket 0044on hub cap 0043.
X Attach lug wrench 0087to socket 0044and
loosen hub cap 0043counter-clockwise.
X Remove hub cap 0043. X
To install: before installing, check hub
cap 0043and the wheel area for soiling and
clean if necessary.
X Put hub cap 0043in position and turn until it is
in the right position.
X Position socket 0044on hub cap 0043.
X Attach lug wrench 0087to socket 0044and
tighten hub cap 0043.
The tightening torque must be
18 lb-ft (25 Nm).
i Note
that the hub cap should be tight-
ened to the specified torque of 18 lb-ft
(25 Nm). Mercedes-Benz recommends
that you have the hub cap installed at a
qualified specialist workshop. X
Using lug wrench 0087, loosen the bolts on
the wheel you wish to change by about one full turn. Do not unscrew the bolts com-
pletely. The jacking points are located just behind the
front wheel housings and just in front of the
rear wheel housings (arrows). 380
Changing a wheelWheels and tires

approved for Mercedes-Benz vehicles and the
respective wheel.
! To prevent damage to the paintwork, hold
the wheel securely against the wheel hub
while screwing in the first wheel bolt. X
Clean the wheel and wheel hub contact
surfaces.
X Slide the wheel to be mounted onto the
alignment bolt and push it on.
X Tighten the wheel bolts until they are fin-
ger-tight.
X Unscrew the alignment bolt.
X Tighten the last wheel bolt until it is finger-
tight.
Lowering the vehicle G
WARNING
The wheels could work loose if the wheel nuts and bolts are not tightened to the specified
tightening torque. There is a risk of accident.
Have the tightening torque immediately
checked at a qualified specialist workshop
after a wheel is changed. X
Place the ratchet wrench onto the hexagon
nut of the jack so that the letters ABare
visible.
X Turn the ratchet wrench until the vehicle is
once again standing firmly on the ground.
X Place the jack to one side.
X Tighten the wheel bolts evenly in a cross-
wise pattern in the sequence indicated ( 0043
to 0083). The tightening torque must be
110 lb-f t(150 Nm) .
X Turn the jack back to its initial position.
X Stow the jack and the rest of the vehicle
tools in the trunk again.
X Check the tire pressure of the newly moun-
ted wheel and adjust it if necessary.
Observe the recommended tire pressure
(Y page 359).
i Vehicles with a tire pressure control sys-
tem: all mounted wheels must be equipped
with functioning tire pressure control sen-
sors. Wheel and tire combinations
General notes
! For safety reasons, Mercedes-Benz rec-
ommends that you only use tires and
wheels which have been approved by
Mercedes-Benz specifically for your vehi-
cle. 382
Wheel and tire combinationsWheels and tires