231 Operation
Driving instructions
Catalytic converter
Your Mercedes-Benz is equipped with
monolithic type catalytic converters, an
important element in conjunction with the
oxygen sensors to achieve substantial con-
trol of the pollutants in the exhaust emis-
sions. Keep your vehicle in proper
operating condition by following our rec-
ommended maintenance instructions as
outlined in your Service Booklet.
Emission control
Certain systems of the engine serve to
keep the toxic components of the exhaust
gases within permissible limits required by
law.
These systems, of course, will function
properly only when maintained strictly ac-
cording to factory specifications. Any ad-
justments on the engine should, therefore,
be carried out only by qualified
Mercedes-Benz Center authorized techni-
cians. Engine adjustments should not be
altered in any way. Moreover, the specified
service jobs must be carried out regularly
according to Mercedes-Benz servicing re-
quirements. For details refer to the Service
Booklet.
!To prevent damage to the catalytic con-
verters, use only premium unleaded
gasoline in this vehicle.
Any noticeable irregularities in engine
operation should be repaired promptly.
Otherwise, excessive unburned fuel
may reach the catalytic converter,
causing it to overheat and start a fire.
Warning!
G
As with any vehicle, do not idle, park or op-
erate this vehicle in areas where combusti-
ble materials such as grass, hay or leaves
can come into contact with the hot exhaust
system, as these materials could be ignited
and cause a vehicle fire.
233 Operation
At the gas station
At the gas station
The fuel filler flap is located on the
right-hand side of the vehicle towards the
rear. Locking/unlocking the vehicle with
the remote control automatically
locks/unlocks the fuel filler flap.
Remove the key from the starter
switch.
Open the fuel filler flap by pushing at
the point indicated by the arrow.
The fuel filler flap springs open.
Turn the fuel cap to the left and hold on
to it until possible pressure is released.
Take off the cap and set it in the recess
on the fuel filler flap.
To prevent fuel vapors from escaping
into open air, fully insert filler nozzle
unit.
Only fill your tank until the filler nozzle
unit cuts out – do not top up or overfill.
Replace the fuel cap by turning it to the
right.
You will hear when the fuel cap is tight-
ened.
Close the fuel filler flap.
Warning!
G
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious inju-
ry. Whenever you are around gasoline, avoid
inhaling fumes and skin contact, extinguish
all smoking materials. Never allow sparks,
flame or smoking materials near gasoline! Warning!
G
Flexible Fuel Vehicles (MY 2003
Mercedes-Benz C 320 models, except those
equipped with manual transmission or
4MATIC*) only:
Ethanol fuel (E85) and its vapors are highly
flammable, poisonous and burn easily. Etha-
nol fuel can cause serious injuries if ignited
or if you come into contact with it or inhale
fumes of it. Avoid inhalation of Ethanol
fumes and skin contact with Ethanol. Extin-
guish all open flames before fueling. Never
smoke or create sparks close to Ethanol.
Warning!
G
Overfilling of the fuel tank may create pres-
sure in the system which could cause a gas
discharge. This could cause the gas to spray
back out when removing the fuel pump noz-
zle, which could cause personal injury.
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).
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.
244 OperationTires and wheelsKeep this in mind when checking tire pres-
sure where the temperature is different
from the outside temperature.
Tire temperature and tire pressure are also
increased while driving, depending on the
driving speed and the tire load.
Check the spare tire periodically for condi-
tion and inflation. Spare tires will age and
b e c o m e w o r n o v e r t i m e e v e n i f n e v e r u s e d ,
and thus should be inspected and replaced
when necessary.
Rotating wheels
On vehicles with the same wheel size all
around, wheels can be rotated every 3 000
to 6 000 miles (5 000 to 10 000 km), or
sooner if necessary, according to the de-
gree of tire wear. The same direction of tire
rotation must be retained.Rotate the wheels before the characteris-
tic tire wear pattern becomes visible
(shoulder wear on front wheels and tread
center wear on rear wheels).
Thoroughly clean the inner side of the
wheels after each rotation. Check and en-
sure proper tire inflation pressure.
Warning!
G
Follow recommended inflation pressures.
Do not overinflate tires. Overinflated tires
can result in sudden deflation (blowout) be-
cause they are more likely to become punc-
tured or damaged by road debris, potholes,
etc.
Do not underinflate tires. Underinflated tires
wear unevenly, adversely affect handling
and fuel economy, and are more likely to fail
from being overheated.
Do not overload the tires by exceeding the
specified vehicle capacity weight (as indicat-
ed by the label on the pillar in the driver’s
door opening). Overloading the tires can
overheat them, possibly causing a blowout.Warning!
G
Rotate front and rear wheels only if they are
of the same size.
Warning!
G
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
80 ft.lb. (110 Nm).
Use only genuine Mercedes-Benz wheel
bolts specified for your vehicle's rims.
249 Operation
Vehicle care
Vehicle care
Cleaning and care of vehicle
While in operation, even while parked, your
vehicle is subject to varying external influ-
ences which, if gone unchecked, can at-
tack the paintwork as well as the
underbody and cause lasting damage.
Such damage is caused not only by ex-
treme and varying climatic conditions, but
also by:
Air pollution
Road salt
Tar, gravel and stone chippingTo avoid paint damage, you should imme-
diately remove:
Grease and oil
Fuel
Coolant
Brake fluid
Insects
Tree resins etc.
Frequent washing reduces and / or elimi-
nates the aggressiveness and potency of
the above adverse influences.
More frequent washings are necessary to
deal with unfavorable conditions:
Near the ocean
In industrial areas (smoke, exhaust
emissions)
During winter operationYou should check your vehicle from time to
time for stone chipping or other damage.
A n y d a m a g e s h o u l d b e r e p a i r e d a s s o o n a s
possible to prevent corrosion.
In doing so, do not neglect the underbody
of the vehicle. A prerequisite for a thor-
ough check is a washing of the underbody
followed by a thorough inspection. Dam-
aged areas need to be re-undercoated.
Your vehicle has been treated at the facto-
ry with a wax-base rustproofing in the body
cavities which will last for the lifetime of
the vehicle. Post-production treatment is
neither necessary nor recommended by
Mercedes-Benz because of the possibility
of incompatibility between materials used
in the production process and others ap-
plied later.
We have selected car-care products and
compiled recommendations which are
specially matched to our vehicles and
which always reflect the latest technology.
You can obtain Mercedes-Benz approved
car-care products at your authorized
Mercedes-Benz Center.
Warning!
G
Many cleaning products can be hazardous.
Some are poisonous, others are flammable.
Always follow the instructions on the partic-
ular container. Always open your vehicle’s
doors or windows when cleaning the inside.
Never use fluids or solvents that are not de-
signed for cleaning your vehicle.
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).
272 Practical hintsWhat to do if …Display
Possible cause
Suggested solution
A
RESERVE FUEL
VISIT FILLING STATION!
The fuel level has dropped below the
reserve mark.
Refuel at the next gas station
(page 233).
J
DOOR OPEN!
You are attempting to drive with one or
more doors open.
Close the doors.
Y
HOOD OPEN!
You are driving with the hood open.
Close the hood (
page 235).
Ê
TRUNK OPEN!
This message will appear whenever the
trunk lid is open.
Close the trunk lid.
I
REPLACE KEY
VISIT WORKSHOP!
No additional code available for
SmartKey.
Visit an authorized Mercedes-Benz
Center as soon as possible.
AUTOM. LIGHT ON
REMOVE KEY!
You have forgotten to remove the key.
Remove the key from the starter
switch.
.
LAMP SENSOR
VISIT WORKSHOP!
The lamp sensor is malfunctioning. The
headlamps switch on automatically.
In the control system, set lamp
operation to manual (
page 119).
Switch on headlamps using the
exterior lamp switch.
LOW BEAM, L
CHECK LAMPS!
The left low beam lamp is malfunctioning.
Visit an authorized Mercedes-Benz
Center as soon as possible.
LOW BEAM, R
CHECK LAMPS!
The right low beam lamp is
malfunctioning.
Visit an authorized Mercedes-Benz
Center as soon as possible.
DISPLAY DEFECTIVE
VISIT WORKSHOP!
The display for the lamps or the system is
malfunctioning.
Visit an authorized Mercedes-Benz
Center as soon as possible.