2005 MERCEDES-BENZ C COUPE service

316 OperationTires and wheelsTire speed rating
The tire speed rating6 (
page 314)
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,
the service description for the tire must
be referred to. The service description is comprised of the tire load rating5
(
page 314) and the tire speed
rating6 (
page 314).
If your tire includes “ZR” in the size
designation and no service
description5 and6 (
page 314) is
given, the tire manufacturer must be
consulted for the maximum speed
capability.
If a service description5 and6
(
page 314) is given, the speed capa-
bility is limited by the speed symbol in
the service description.
Example: 245/40 ZR18 97Y.
In this example, “97Y” is the service
description. The letter “Y” designates
the speed rating and the speed capabil-
ity of the tire is limited to 186 mph
(300 km/h).
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. iTire load rating5 (
page 314) and
tire speed rating6 (page 314) are
also referred to as “service descrip-
tion”.
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)

317 Operation
Tires and wheels


Any tire with a speed capability above
186 mph (300 km/h) must include a
“ZR” in the size designation AND the
service description must be placed in
parenthesis. Example: 275/40 ZR 18
(99Y). The “(Y)” speed rating in paren-
thesis designates the maximum speed
capability of the tire as being above
186 mph (300 km/h). Consult the tire
manufacturer for the actual maximum
permissible speed of the tire.
All-season and winter tires
Load identification
1Load identificationIn addition to tire load rating, special load
information may be molded into the tire
sidewall following the letter designating
the tire speed rating1 (
page 317).
No specification given: absence of any text
(like in above example) indicates a
standard load (SL) tire.
XL or Extra Load: designates an extra load
(or reinforced) tire.
Light Load: designates a light load tire.
C, D, E: designates load range associated
with the maximum load a tire can carry at
a specified pressure.
Index
Speed rating
QM+S
up to 100 mph (160 km/h)
TM+S
up to 118 mph (190 km/h)
HM+S
up to 130 mph (210 km/h)
VM+S
up to 149 mph (240 km/h)
iThe marking “M+S” next to the service
description designates tires with mud
and snow capabilities.
iFor illustration purposes only. Actual
data on tires is specific to each vehicle
and may vary from data shown in above
illustration.

321 Operation
Tires and wheels
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.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.
Treadwear
Traction
Temperature
200
AA
A
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.

328 OperationWinter drivingBefore the onset of winter, have your
vehicle winterized at an authorized
Mercedes-Benz Center.
This service includes:

Check of anticorrosion and antifreeze
concentration.


Addition of cleaning concentrate to the
water of the windshield and headlamp
cleaning system. Add MB Concentrate
“S” to a premixed windshield washer
solvent / antifreeze which is formulated
for temperatures below freezing point
(page 435).


Battery test. Battery capacity drops
with decreasing ambient temperature.
A well charged battery helps to ensure
that the engine can be started, even at
low ambient temperatures.


Tire change. Mercedes-Benz recom-
mends M+S rated radial-ply tires with a
minimum tread depth of approximately 1/6 in (4 mm) on all four wheels for the
winter season.
Winter tires
Always use winter tires at temperatures
below 45°F (7°C) and whenever wintry
road conditions prevail. Use of winter tires
is the only way to achieve the maximum
effectiveness of the ABS and ESP in winter
operation.
For safe handling, make sure that all
mounted winter tires are of the same make
and have the same tread design.Always observe the speed rating of the
winter tires installed on your vehicle. If the
maximum speed for which your tires are
rated is below the speed rating of your
vehicle, you must place a notice to this
effect where it will be seen by the driver.
Such notices are available at your tire deal-
er or any authorized Mercedes-Benz
Center.Warning!
G
Winter tires with a tread depth under
1/6 in
(4 mm) must be replaced. They are no long-
er suitable for winter operation.
Warning!
G
If you use your spare tire when winter tires
are fitted on the other wheels, be aware that
the difference in tire characteristics may
very well impair turning stability and that
overall driving stability may be reduced.
Adapt your driving style accordingly.
Have the spare tire replaced with a winter
tire at the nearest authorized
Mercedes-Benz Center.

330 OperationMaintenanceIn the “Operation” section you will find
detailed information on operating,
maintaining and caring for your vehicle.
We strongly recommend that you have
your vehicle serviced by an authorized
Mercedes-Benz Center, in accordance with
the Maintenance Booklet at the times
called for by the maintenance service
indicator display.
Failure to have the vehicle maintained in
accordance with the Maintenance Booklet
and maintenance service indicator at the
designated times /mileage will result in
vehicle damage not covered by the
Mercedes-Benz Limited Warranty.
The maintenance service indicator will
notify you when your next maintenance
service is due.Starting approximately one month before
your next maintenance service is due, one
of the following messages will appear in
the multifunction display while you are
driving or when you switch on the ignition
(example service A):
Service A in XX Days
Service A in XX Miles (Km)
A Service due nowThe type of maintenance service due is
indicated in the multifunction display:
9Minor service (A)
´Major service (B)
iVehicles equipped with FSS (F
lexible
S
ervice S
ystem) only (Canada
vehicles): The interval between
maintenance services depends on your
driving habits. A gentle driving style,
moderate engine speeds and the
avoidance of short-distance trips will
lengthen the interval between services.

331 Operation
Maintenance
Clearing the maintenance service indicator
The maintenance service indicator is
automatically cleared

after ten seconds when you switch on
the ignition or when reaching the main-
tenance service threshold while driving


after 30 seconds, once the suggested
maintenance service term has passed
You can also clear it yourself.
1Reset button

Press reset button1 on the
instrument cluster.
Maintenance service term exceeded
If you have exceeded the suggested
maintenance service term, you will see the
following message in the multifunction
display:Service A exceeded by XX Days
Service A exceeded by XX Miles
(Km)
In addition, a signal sounds when the
message appears.
Any authorized Mercedes-Benz Center will
reset the maintenance service indicator
following a completed maintenance
service.Calling up the maintenance service
indicator
Switch on the ignition (
page 33).
The standard display of the control
system appears (
page 128).

Press buttonk orj on the
multifunction steering wheel until the
maintenance service indicator with the
service symbol9 or´ and the
service deadline appears in the
multifunction display.iIf the battery is disconnected, the days
of disconnection will not be included in
the count shown by the maintenance
service indicator. To arrive at the true
maintenance service deadline, you will
need to subtract these days from the
days shown in the maintenance service
indicator.
Do not confuse the maintenance
service indicator with the engine oil
level indicator:.

332 OperationMaintenanceResetting the maintenance service indicator
In the event that the maintenance service
on your vehicle is not carried out by an
authorized Mercedes-Benz Center, you can
have the maintenance service indicator
reset. The automotive maintenance facility
carrying out the maintenance service will
find the information for resetting the
maintenance service indicator in the
maintenance-relevant information for your
vehicle. Such information is available from
either your authorized Mercedes-Benz
Center or directly from Mercedes-Benz.
iIf the maintenance service indicator
was inadvertently reset, have an
authorized Mercedes-Benz Center
correct it.
Only reset if the proper maintenance
service has been performed. Resetting
the system without performing the
proper service as called for by the
maintenance service indicator will
result in engine damage and/or other
vehicle damage not covered by the
Mercedes-Benz Limited Warranty.

342 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
ú
(USA only)
±
(Canada only)
The yellow engine
malfunction indicator
lamp comes on while
driving.
There is a malfunction in:

The fuel management system


The ignition system


The emission control system


Systems which affect emissions
Such malfunctions may result in ex-
cessive emissions values and may
switch the engine to its limp-home
(emergency operation) mode.

Have the vehicle checked as soon as possi-
ble by an authorized Mercedes-Benz Center.
An on-board diagnostic connector is used
by the service station to link the vehicle to
the shop diagnostics system. It allows the
accurate identification of system
malfunctions through the readout of
diagnostic trouble codes. It is located in the
front left area of the footwell next to the
parking brake pedal.
A loss of pressure has been detect-
ed in the fuel system. The fuel cap
may not be closed properly or the
fuel system may be leaky.

Check the fuel cap (
page 288).
If it is not closed properly:

Close the fuel cap.
If it is closed properly:

Have the fuel system checked by an
authorized Mercedes-Benz Center.
Your fuel tank is empty.

After refuelling start, turn off and restart the
engine three or four times in succession.
The limp-home mode is canceled. You do not
need to have your vehicle checked.