Heat MERCEDES-BENZ S550 2007 W221 Service Manual

517 Operation
Tires and wheels
If you wish to confirm activation:
Press$ or% to select “Yes”.

Press#.
The message
Run Flat Indicator
reactivated
appears in the multifunction display.
After a certain “learning phase”, the Run
Flat Indicator checks the set pressure val-
ues for all four tires.
If you wish to cancel activation:

PressL.
or
When the message
Tire pressure
now OK?
appears in the multifunction display:

Press$ or% to select “No”.

Press#.Potential problems associated with
underinflated and overinflated tires
Underinflated tires
Underinflated tires can:


cause excessive and uneven tire wear


adversely affect fuel economy


lead to tire failure from being
overheated


adversely affect handling
characteristicsOverinflated tires
Overinflated tires can:


adversely affect handling
characteristics


cause uneven tire wear


be more prone to damage from road
hazards


adversely affect ride comfort


increase stopping distance
Warning!
G
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.
Warning!
G
Follow recommended tire inflation
pressures.
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.

520 OperationTires and wheels
For additional information on tire load
rating, see “Load identification”
(page 521).
Tire speed rating
The tire speed rating6 (
page 518)
indicates the approved maximum speed
for the tire.Summer tires


At the tire manufacturer’s option, any
tire with a speed capability above
149 mph (240 km/h) can include a
“ZR” in the size designation (for exam-
ple: 245/40 ZR18). To determine the
maximum speed capability of the tire,
Warning!
G
The tire load rating must always be at least
half of the GAWR (
page 526) of your vehi-
cle. Otherwise, tire failure may be the result
which may cause an accident and/or seri-
ous personal injury to you or others.
Always replace rims and tires with the same
designation, manufacturer and type as
shown on the original part.
Warning!
G
Do not overload the tires by exceeding the
specified load limit or vehicle capacity
weight as indicated on the placard located
on the driver’s door B-pillar (
page 503).
Overloading the tires can overheat them,
possibly causing a blowout. Overloading the
tires can also result in handling or steering
problems, or brake failure.
i
Tire load rating5 (
page 518) and tire
speed rating6 (
page 518) are also referred
to as “service description”.
Warning!
G
Even when permitted by law, never operate
a vehicle at speeds greater than the
maximum speed rating of the tires.
Exceeding the maximum speed for which
tires are rated can lead to sudden tire
failure, causing loss of vehicle control and
possibly resulting in an accident and/or
personal injury and possible death, for you
and for others.
i
Tire load rating5 (
page 518) and tire
speed rating6 (
page 518) are also referred
to as “service description”.
Index
Speed rating
Q
up to 100 mph (160 km/h)
R
up to 106 mph (170 km/h)
S
up to 112 mph (180 km/h)
T
up to 118 mph (190 km/h)
H
up to 130 mph (210 km/h)
V
up to 149 mph (240 km/h)
W
up to 168 mph (270 km/h)
Y
up to 186 mph (300 km/h)
(Y)
above 186 mph (300 km/h)
ZR
above 149 mph (240 km/h)

523 Operation
Tires and wheels
Date of manufacture
The date of manufacture5 (
page 522)
identifies the week and year of manufac-
ture.
The first two figures identify the week,
starting with “01” to represent the first full
week of the calendar year. The second two
figures represent the year.
For example, “3202” represents the 32nd
week of 2002.
Maximum tire load
1Maximum tire load ratingThe maximum tire load is the maximum
weight the tires are designed to support.
For more information on tire load rating
(
page 519).
For information on calculating total and
cargo load capacities (
page 505).
Maximum tire inflation pressure
1Maximum permissible tire inflation
pressure
This is the maximum permissible tire
inflation pressure for the tire.
Always follow the recommended tire
inflation pressure (
page 509) for proper
tire inflation.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.Warning!
G
Do not overload the tires by exceeding the
specified load limit or vehicle capacity
weight as indicated on the placard located
on the driver’s door B-pillar (
page 503).
Overloading the tires can overheat them,
possibly causing a blowout. Overloading the
tires can also result in handling or steering
problems, or brake failure.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.

524 OperationTires and wheelsUniform Tire Quality Grading Standards (U.S. vehicles)
Tire manufacturers are required to grade
tires based on three performance
factors: treadwear, traction and
temperature resistance.1Treadwear
2Traction
3Temperature resistance
Quality grades can be found, where appli-
cable, on the tire sidewall between tread
shoulder and maximum section width. For
example:All passenger car tires must conform to
federal safety requirements in addition to
these grades.
Treadwear
The treadwear grade is a comparative rat-
ing based on the wear rate of the tire when
tested under controlled conditions on a
specified government test course. For ex-
ample, a tire graded 150 would wear one
and one-half (1
1/2) times as well on the
government course as a tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly
from the norm due to variations in driving
habits, service practices and differences in
road characteristics and climate.
Warning!
G
Never exceed the max. tire inflation
pressure. Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and / or unevenly, adverse-
ly 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 com-
fort, wear unevenly, increase stopping dis-
tance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road de-
bris, potholes etc.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
Treadwear
Traction
Temperature
200
AA
A

525 Operation
Tires and wheels
Traction
The traction grades, from highest to low-
est, are AA, A, B, and C. Those grades rep-
resent the tire’s ability to stop on wet
pavement as measured under controlled
conditions on specified government test
surfaces of asphalt and concrete. A tire
marked C may have poor traction perfor-
mance.
Temperature
The temperature grades are A (the high-
est), B, and C, representing the tire’s resis-
tance 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 tem-perature can cause the material of the tire
to degenerate and reduce tire life, and ex-
cessive temperature can lead to sudden
tire failure. The grade C corresponds to the
minimum 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 ply material
1Plies in sidewall
2Plies under tread
This marking tells you about the type of
cord and number of plies in the sidewall
and under the tread.
Warning!
G
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
Warning!
G
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underin-
flation, or excessive loading, either sepa-
rately or in combination, can cause
excessive heat build-up and possible tire
failure.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.

526 OperationTires and wheelsTire 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 3 hours or driv-
en 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 (D
epartment o
f T
ransportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross A
xle W
eight R
ating)
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 V
ehicle W
eight)
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.

554 Practical hintsWhat to do if …?Warning!
G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle placard or the tire inflation pressure
label. (If your vehicle has tires of a different
size than the size indicated on the vehicle
placard or the tire inflation pressure label,
you should determine the proper tire infla-
tion pressure for those tires).
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires is significantly under-inflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible, and inflate them to
the proper pressure. Driving on a significant-
ly under-inflated tire causes the tire to over-
heat and can lead to tire failure.
Under-inflation also reduces fuel efficiency
and tire tread life, and may affect the vehi-
cle’s handling and stopping ability. Please
note that the TPMS is not a substitute for
proper tire maintenance, and it is the driv-
er’s responsibility to maintain correct tire
pressure, even if under-inflation has not
reached the level to trigger illumination of
the TPMS low tire pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate
when the system is not operating properly.
The TPMS malfunction indicator is com-
bined with the low tire pressure telltale.
When the system detects a malfunction, the
telltale will flash for approximately
one minute and then remain continuously
illuminated. This sequence will continue
upon subsequent vehicle start-ups as long
as the malfunction exists. When the mal-
function indicator is illuminated, the system
may not be able to detect or signal low tire
pressure as intended.
TPMS malfunctions may occur for a variety
of reasons, including the installation of
replacement or alternate tires or wheels on
the vehicle that prevent the TPMS from
functioning properly. Always check the
TPMS malfunction telltale after replacing
one or more tires or wheels on your vehicle
to ensure that the replacement or alternate
tires and wheels allow the TPMS to continue
to function properly.

559 Practical hints
What to do if …?
Text messagesDisplay
Possible cause/consequence
Possible solution
Apply brake
to shift
from ’P’
You have tried to Shift the automatic trans-
mission to D, R or N without stepping on
the brake.

Step on brake.
USA only:
Cruise control
- - - mph
Canada only:
Cruise control
- - - km/h
You have tried to switch on cruise control
below a speed of 20 mph (30 km/h).

Drive faster than 20 mph (30 km/h) and save the speed.
ESP
® is deactivated.

Activate ESP
® (page 72).
The automatic transmission is in position P,
R or N.

Shift the automatic transmission toD (
page 367).
The system is overheated.

Wait until the system cools down.
The vehicle is secured in place by the elec-
tric parking brake.

Release electric parking brake (
page 364).
Cruise control
inoperative
Cruise control is malfunctioning.

Have cruise control checked by an authorized Mercedes-Benz
Center.

560 Practical hintsWhat to do if …?Display
Possible cause/consequence
Possible solution
DISTRONIC PLUS
currently unavailable
See Oper. Manual
You attempt to activate DISTRONIC Plus*
even though you have switched off the ra-
dar sensors* on the vehicle.

Check if the radar sensors* may be switched on (
page 256).

Switch on the radar sensors* using the instrument cluster
control system.
DISTRONIC Plus* is switched off and is
temporarily unavailable.
DISTRONIC Plus* is deactivated if:

the DISTRONIC Plus* cover in the radia-
tor grille is dirty


the radar sensors* does not sense any
other vehicles or objects, i.e. road sign
or similar to this, for a long time


the system is overheated


its function is impaired as a result of
heavy precipitation or fog


the battery voltage is insufficient

Clean the DISTRONIC Plus* cover in the radiator grille
(page 537).

Restart the vehicle.

Try activating DISTRONIC Plus* again later.

Wait until the system cools down or the battery recovers.
DISTRONIC Plus* will be operational again without you needing to
restart the engine if:


the dirt (e.g. slush) loosens while you are driving


the system detects that the sensors* are fully available again


the message in the multifunction display disappears
DISTRONIC Plus* is switched off because
the radar sensor system* is temporarily in-
operative due to electromagnetic interfer-
ence near television and radio transmitter
stations, toll stations, speed measuring sys-
tems, etc.

Wait until the message in the multifunction display disappears.

561 Practical hints
What to do if …?
Display
Possible cause/consequence
Possible solution
DISTRONIC PLUS
inoperative
DISTRONIC Plus* is malfunctioning.

Visit an authorized Mercedes-Benz Center as soon as possible.
DISTRONIC PLUS
passive
You have depressed the accelerator pedal,
DISTRONIC Plus* is no longer controlling
the speed of the vehicle.

Release the accelerator pedal.
USA only:
DISTRONIC PLUS
- - - mph
Canada only:
DISTRONIC PLUS
- - - km/h
You have attempted to activate DISTRONIC
Plus* at a speed below 20 mph (30 km / h)
without the vehicle in front being displayed
in the multifunction display (
page 385).

Drive faster than 20 mph (30 km / h) and activate DISTRONIC
Plus* again.
ESP
® is deactivated.

Activate ESP
® (page 72).
The automatic transmission is in position P,
R or N.

Shift the automatic transmission toD (
page 367).
The system is overheated.

Wait until the system cools down.
The vehicle is secured in place by the elec-
tric parking brake.

Release electric parking brake (
page 364).
The driver’s door is open and the drivers
seat belt is unbuckled.

Close the driver’s door and fasten your seat belt.
The hood is open.

Close the hood (
page 493).