233 Operation
At 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 330).
3Windshield washer and headlamp
cleaning system
For more information on refilling the
reservoir, see the “Operation” section
(page 240).Engine oil level
More information on engine oil can be
found in the “Operation” section
(
page 235).
Opening hood (
page 234).
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 292).
Exterior lamp switch (
page 98).
Tire inflation pressure
More information on tire inflation pressure
can be found in the “Operation” section
(
page 242).
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 C320 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 332).
iLeaving the engine running and the fuel
cap open can cause the
?
lamp to
illuminate.
See also “Practical hints” section
(
page 258).
S203 MY03_A.book Page 233 Tuesday, January 28, 2003 2:22 PM
235 Operation
Engine compartment
Closing
Let the hood drop from a height of ap-
proximately 1ft (30cm).
The hood will lock audibly.
Check to make sure that the hood is
fully closed.
If you can raise the hood at a point
above the headlamps, then it is not
properly closed. Open it again and let it
drop with somewhat greater force.
Engine oil
The amount of oil your engine needs will
depend on a number of factors, including
driving style. Higher oil consumption can
occur when
the vehicle is new
the vehicle is driven frequently at high-
er engine speeds.
Engine oil consumption checks should only
be made after the vehicle break-in period.
Checking engine oil level
When checking the oil level the vehicle
must
be parked on level ground
be at normal operating temperature
have been stationary for at least five
minutes with the engine turned off
Warning!
G
If you see flames or smoke coming from the
engine compartment, or if the coolant tem-
perature display indicates that the engine is
overheated, do not open the hood. Move
away from vehicle and do not open the hood
until the engine has cooled. If necessary,
call the fire department.Warning!
G
The engine is equipped with a transistorized
ignition system. Because of the high voltage
it is dangerous to touch any components (ig-
nition coils, spark plug sockets, diagnostic
socket) of the ignition system
with the engine running
while starting the engine
if ignition is “on” and the engine is
turned manually
Warning!
G
Be careful that you do not close the hood on
anyone
S203 MY03_A.book Page 235 Tuesday, January 28, 2003 2:22 PM
236 OperationEngine compartmentYou can check the engine oil level on the
multifunction display.
Turn the key in the starter switch to
position2.
The standard display (
page 112) should
appear in the multifunction display.
Press button
k
or
j
on the
steering wheel until the following mes-
sage is seen in the multifunction dis-
play:
ENGINE OIL LEVEL – MEASUREMENT IN
PROCESS! CORRECT MEASUREMENT ONLY
IF VEH. LEVEL
After about three seconds this mes-
sage is displayed:
ENGINE OIL LEVEL –
MEASURING NOW
One of the following messages will sub-
sequently appear in the indicator:
ENGINE OIL LEVEL – OK
ENGINE OIL LEVEL – ADD 1 QUART
(1.0 LITER)!
ENGINE OIL LEVEL – ADD
1.5 QUARTS (1.5 LITERS)!
ENGINE OIL LEVEL – ADD 2 QUARTS
(2.0 LITERS)!
Adding engine oil
1Filler neck
Unscrew the cap from filler neck1. Be
careful not to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.!Excessive oil must be siphoned or
drained off. It could cause damage to
the engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.
S203 MY03_A.book Page 236 Tuesday, January 28, 2003 2:22 PM
237 Operation
Engine compartment
Screw the cap back on the filler neck.
Other display messages
If there is excessive engine oil with the en-
gine at normal operating temperature, the
following message will appear:
ENGINE OIL LEVEL – REDUCE OIL LEVEL
Have excess oil siphoned.
If the key is not turned to position2 in the
starter switch, the following message will
appear:
FOR ENGINE OIL LEVEL IGNITION ON
PLEASE!
Switch on the ignition.If you see the message:
OBSERVE WAITING PERIOD
Wait five minutes before repeating
check procedure.
If you see the message:
ENGINE OIL LEVEL – NOT WHEN ENGINE ON!
Turn off the engine. If engine is at nor-
mal operating temperature, wait five
minutes before checking oil. If the en-
gine is not yet at normal operating tem-
perature, you must wait 30 minutes
before checking oil.
If a proper oil level check cannot be per-
formed, the following message will appear:
MEASURING NOT POSSIBLE
.
Repeat the engine oil level check after
a short while.
More information on engine oil can be
found in the “Technical data” section
(
page 330).
Transmission fluid level
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Center
check the automatic transmission.
S203 MY03_A.book Page 237 Tuesday, January 28, 2003 2:22 PM
238 OperationEngine compartmentCoolant level
The engine coolant is a mixture of water
and anticorrosion/antifreeze. To check
the coolant level, the vehicle must be
parked on level ground and the engine
must be cool.
The coolant expansion tank is located on
the passenger side of the engine compart-
ment.
1Coolant expansion tank
Using a rag, turn the cap slowly approx-
imately one half turn to the left to re-
lease any excess pressure.
Continue turning the cap to the left and
remove it.
The coolant level is correct if the level
for cold coolant: reaches the black
top part of the reservoir
for warm coolant: is approx. 0.6 in
(1.5 cm) higher
Add coolant as required.
Replace and tighten cap.
More information on coolant can be found
in the “Technical data” section
(
page 334).
Warning!
G
In order to avoid any possibly serious burns:
Use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system,
or if the coolant temperature display in-
dicates that the coolant is overheated.
Do not remove pressure cap on coolant
reservoir if engine temperature is above
194°F (90°C). Allow engine to cool
down before removing cap. The coolant
reservoir contains hot fluid and is under
pressure.
Using a rag, slowly open the cap approx-
imately ½ turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out un-
der pressure.
Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.
S203 MY03_A.book Page 238 Tuesday, January 28, 2003 2:22 PM
239 Operation
Engine compartment
Battery
Your vehicle’s battery is located in the en-
gine compartment.
The battery should always be sufficiently
charged in order to achieve its rated ser-
vice life.
If you use your vehicle mostly for short dis-
tance trips, you will need to have the bat-
tery charge checked more frequently.
When replacing the battery, always use
batteries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Center about
steps you need to observe.Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
G
Observe all safety instructions
and precautions when handling
automotive batteries.
A
Risk of explosion
D
Keep flames or sparks away
from battery. Do not smoke.
B
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
In case it does, immediately
flush affected area with clear
water and seek medical help if
necessary.
E
Wear eye protection.
C
Keep children away.
F
Follow the instructions in this
Operator's Manual.
S203 MY03_A.book Page 239 Tuesday, January 28, 2003 2:22 PM
244 OperationWinter driving
Winter drivingBefore 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 pre-mixed windshield washer
solvent/antifreeze which is formulated
for below freezing temperatures
(page 336).
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 the 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.
S203 MY03_A.book Page 244 Tuesday, January 28, 2003 2:22 PM
257 Practical hints
What to do if …
Problem
Possible cause
Suggested solution
3
;
(Canada only)
(USA only)The red brake warning lamp
lights up while driving and you
hear a warning sound.
You are driving with the parking brake set.
Release the parking brake (
page 46).
The red brake warning lamp
lights up while driving.
There is insufficient brake fluid in the reser-
voir.
Risk of accident! Carefully stop the
vehicle and notify an authorized
Mercedes-Benz Center. Do not add
brake fluid! This will not solve the
problem.
Warning!
G
Driving with the brake warning lamp illumi-
nated can result in an accident. Have your
brake system checked immediately if the
brake warning lamp stays on. Don’t add
brake fluid before checking the brake sys-
tem. Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot engine
parts and the brake fluid catching fire. You
can be seriously burned.
!If you find that the brake fluid in the
brake fluid reservoir has fallen to the
minimum mark or below, have the
brake system checked for brake pad
thickness and leaks.
S203 MY03_A.book Page 257 Tuesday, January 28, 2003 2:22 PM