234 OperationAt the gas station
Check regularly and before a long trip
1Coolant level
More information on the coolant level
can be found in the “Operation” section
(
page 238).
2Brake fluid (fuse box cover removed)
More information on brake fluid can be
found in the “Technical data” section
(page 332).
Removing fuse box cover
(page 312).
3Windshield washer and headlamp
cleaning system*
For more information on refilling the
reservoir, see the “Operation” section
(page 241).Engine oil level
More information on engine oil can be
found in the “Operation” section
(
page 236).
Opening hood (
page 235).
Coolant
For normal replenishing, use water (pota-
ble water quality). More information on
coolant can be found in the “Operation”
section (
page 238).
Vehicle lighting
Check function and cleanliness. For more
information on replacing light bulbs, see
the “Practical hints” section (
page 290).
Exterior lamp switch (
page 101).
Tire inflation pressure
More information on tire inflation pressure
can be found in the “Operation” section
(
page 243).
iUse only premium unleaded gasoline
with a minimum Posted Octane Rating
of 91 (average of 96 RON / 86 MON).
Information on gasoline quality can
normally be found on the fuel pump.
More information on gasoline can be
found in the Factory Approved Service
Products pamphlet.
Flexible Fuel Vehicles (MY 2003
Mercedes-Benz C 320 models, except
those equipped with manual transmis-
sion or 4MATIC*):
More information on Flexible Fuel Vehi-
cles can be found in the “Technical da-
ta” section (
page 334).
iLeaving the engine running and the fuel
cap open can cause the
?
lamp to
illuminate.
See also “Practical hints” section
(
page 259).
242 OperationTires and wheels
Tires and wheelsSee your authorized Mercedes-Benz Cen-
ter for information on tested and recom-
mended rims and tires for summer and
winter operation. They can also offer ad-
vice concerning tire service and purchase.
Retread tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on
retreads. Mercedes-Benz can therefore
not assure the operating safety of the vehi-
cle when such tires are used.
See your authorized Mercedes-Benz Cen-
ter for information on tested and recom-
mended rims and tires for summer and
winter operation.
Important guidelines
Use only sets of tires and rims of the
same type and make.
Tires must be of the correct size for the
rim.
Break in new tires for approximately
60 miles (100 km) at moderate
speeds.
Regularly check the tires and rims for
damage.
If vehicle is heavily loaded, check tire
pressure and correct as required.
Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths under
1/8in (3 mm).
When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!
G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See your authorized
Mercedes-Benz Center for further informa-
tion. If incorrectly sized rims and tires are
mounted:
The wheel brakes or suspension compo-
nents can be damaged
The correct operating clearance of the
wheels and the tires are no longer guar-
anteed
Warning!
G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, use only genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can re-
sult in the bolts loosening and possibly an
accident.
243 Operation
Tires and wheels
Life of tire
The service life of a tire is dependent upon
varying factors including but not limited to:
Driving style
Tire pressure
Distance driven
Direction of rotation
Unidirectional tires offer added advantag-
es, such as better aquaplaning perfor-
mance. To benefit, however, you must
ensure that the tires rotate in the direction
specified.
An arrow on the sidewall indicates the in-
tended direction of tire rotation.Checking tire inflation pressure
Regularly check your tire pressure at inter-
vals of no more than 14 days.
Correct the tire pressure only when tires
are cold.If the tires are warm you should only cor-
rect the tire pressure if it is too low for cur-
rent operating conditions.
A table on the fuel filler flap lists the spec-
ified tire inflation pressures for warm and
cold tires as well as for various operating
conditions.
Tire pressure changes by approx. 1.5 psi
(0.1 bar) per 18°F (10°C) of air tempera-
ture change.
Warning!
G
Tires and spare tire should be replaced after
six years, regardless of the remaining tread.!Keep unmounted tires in a cool, dry
place with as little exposure to light as
possible. Protect tires from contact
with oil, grease and gasoline.
Warning!
G
If the tire pressure repeatedly drops
check the tires for punctures from for-
eign objects
check to see whether air is leaking from
the valves or from around the rim
iThe pressures listed for light loads are
minimum values offering high driving
comfort.
Increased inflation pressures listed for
heavier loads may also be used for light
loads. These higher pressures produce
favorable handling characteristics. The
ride of the vehicle, however, will be
somewhat harder. Never exceed the
max. values or inflate tires below the
min. values listed in the fuel filler flap.
245 Operation
Winter driving
Winter driving
Before the onset of winter have your vehi-
cle winterized at an authorized
Mercedes-Benz Center. This service in-
cludes:
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 below freezing temperatures
(page 338).
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. We recommend M+S rat-
ed radial-ply tires on all four wheels for
the winter season.
Winter tires
Always use winter tires at temperatures
below 39°F (4°C) and whenever wintry
road conditions prevail. Use of winter tires
is the only way to achieve the maximum ef-
fectiveness of ABS, ESP and 4MATIC* in
winter operation.
For safe handling, ensure 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 ve-
hicle, you must place a notice to this effect
where it will be seen by the driver. Such no-
tices are available from your tire dealer or
from any authorized Mercedes-Benz Cen-
ter.Warning!
G
Winter tires with a tread depth under 0.16 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.
247 Operation
Maintenance
Maintenance
We strongly recommend that you have
your vehicle serviced by your authorized
Mercedes-Benz Center, in accordance with
the Service Booklet at the times called for
by the FSS (Flexible Service System).
Failure to have the vehicle maintained in
accordance with the Service Booklet at the
designated times /mileage called for by
the FSS may result in vehicle damage not
covered by the Mercedes-Benz Limited
Warranty.
FSS will notify you when your next service
is due.
Approximately one month before your next
service is due, one of the following mes-
sages will appear in the multifunction dis-
play 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)
SERVICE A DUE NOW!
The type of service due is indicated in the
speedometer display field:9
Minor service (A)
½
Major service (B)
Clearing the service indicator
The service indicator is automatically
cleared
after ten seconds when you switch on
the ignition or when reaching the ser-
vice threshold while driving
after 30 seconds, once the suggested
service term has passed
You can also clear it yourself.
Press the reset knob on the instrument
cluster (
page 22).
Service term exceeded
If you have exceeded the suggested ser-
vice term, you will see the following mes-
sage in the multifunction display:SERVICE A EXCEEDED BY XX DAYS
SERVICE A EXCEEDED BY XX MILES (KM)The Mercedes-Benz Center will reset the
service indicator following a completed
service.
iThe interval between 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.
248 OperationMaintenanceCalling up the service indicator
Switch ignition on.
The standard display of the control sys-
tem appears (
page 116).
Press button
k
or
j
on the mul-
tifunction steering wheel until the FSS
indicator appears in the multifunction
display.
Resetting the service indicator
In the event that the service on your vehi-
cle is not carried out by an authorized
Mercedes-Benz Center, you can reset the
service indicator yourself.
Switch ignition on.
The standard display of the control sys-
tem appears (
page 116).
Press button
k
or
j
on the mul-
tifunction steering wheel until the FSS
indicator appears in the multifunction
display.
Press the reset knob for about four
seconds.
This message appears in the tachome-
ter:DO YOU WANT TO RESET SERVICE INTER-
VAL? CONFIRM BY PRESSING RESET (R)
BUTTON
To confirm, hold down the reset knob
until you hear a signal.The service indicator now displays the
reset interval.
iIf the battery is disconnected, the days
of disconnection will not be included in
the count shown by the service indica-
tor. To arrive at the true service dead-
line, you will need to subtract these
days from the days shown in the ser-
vice indicator.
Do not confuse the service indicator
with the engine oil level indicator
:
.
iIf the service indicator was inadvertent-
ly reset, have a Mercedes-Benz Center
correct it.
Only reset if the proper service has
been performed. Resetting the system
without performing proper service as
called for by the FSS will cause the FSS
to incorrectly determine the next
service interval which will result in
engine damage not covered by the
Mercedes-Benz Limited Warranty.
259 Practical hints
What to do if …
Problem
Possible cause
Suggested solution
?
The yellow “CHECK 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 excessive
emissions values and may switch the engine
to its limp-home (emergency operation)
mode.
Have the vehicle checked as soon as
possible 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 sys-
tem. It allows the accurate identifica-
tion of system malfunctions through
the readout of diagnostic trouble
codes. It is located in the front left
area of the footwell next to the park-
ing brake pedal.
The fuel cap is not closed tight.
Check the fuel cap.
Your gas tank is empty.
After refuelling start the engine three
or four times in succession.
The limp-home mode is canceled. You do
not need to have your vehicle checked.
<
The red seat belt warning lamp
blinks for a brief period after
starting the engine.
The warning lamp reminds you to fasten seat
belts.
Fasten your seat belt.
The yellow fuel tank reserve warning lamp
lights while driving.
The fuel level has gone below the reserve
mark.
Refuel at the next gas station
(page 233).
263 Practical hints
What to do if …
BAS
BRAKE ASSIST
VISIT WORKSHOP!
The BAS has detected a malfunction and
switched off. The brake system is still
functioning normally but without the BAS
available.
Continue driving with added caution.
Have the system checked at an
authorized Mercedes-Benz Center as
soon as possible.
Failure to follow these instructions
increases the risk of accident.
DISPLAY DEFECTIVE
VISIT WORKSHOP!
The BAS or the BAS display is
malfunctioning.
Continue driving with added caution.
Have the system checked at an
authorized Mercedes-Benz Center as
soon as possible.
Failure to follow these instructions
increases the risk of accident.
#
BATTERY/ALTERNATOR
VISIT WORKSHOP!
The battery was charged with a battery
charger or jump started.
Have the battery checked at a service
station.
Display
Possible cause
Suggested solution