2003 MERCEDES-BENZ C CLASS COUPE engine coolant

223
Operation
Driving instructions
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.
Coolant temperature
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to approx. 248°F
(120°C). The engine should not be operated with
the coolant temperature over 248°F
(120°C). Doing so may cause serious en-
gine damage which is not covered by the
Mercedes-Benz Limited Warranty.
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.
Warning!
G
Inhalation of exhaust gas is hazardous to
your health. All exhaust gas contains carbon
monoxide, and inhaling it can cause uncon-
sciousness and lead to death.
Do not run the engine in confined areas
(such as a garage) which are not properly
ventilated. If you think that exhaust gas
fumes are entering the vehicle while driving,
have the cause determined and corrected
immediately. If you must drive under these
conditions, drive with at least one window
fully open at all times.
Warning!
G


Driving when your engine is badly over-
heated can cause some fluids, which
may have leaked into the engine com-
partment, to catch fire. You could be se-
riously burned.


Steam from an overheated engine can
cause serious burns and can occur just
by opening the engine hood. Stay away
from the engine if you see or hear steam
coming from it. Turn off the engine, get
out of the vehicle and do not stand near
the vehicle until it cools down.

225
Operation
At the gas station
Check regularly and before a long trip
1 Coolant level
More information on the coolant level
can be found in the “Operation” section
(
page 229).
2 Brake fluid (fuse box cover removed)
More information on brake fluid can be
found in the “Technical data” section
(page 317).
Removing fuse box cover see page
(page 303).
3 Windshield washer and headlamp
cleaning system
For more information on refilling the
reservoir, see the “Operation” section
(page 232). Engine oil level
More information on engine oil can be
found in the “Operation” section
(
page 227).
Opening hood see (
page 226).
Coolant
For normal replenishing, use water (pota-
ble water quality). More information on
coolant can be found in the“Operation”
section (
page 229).
Vehicle lighting
Check function and cleanliness. For more
information on replacing light bulbs, see
the “Practical hints” section (
page 280).
Exterior lamp switch (
page 96).
Tire inflation pressure
More information on tire inflation pressure
can be found in the “Operation” section
(
page 234).
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.iLeaving the engine running and the fuel
cap open can cause the
?
lamp to
illuminate.
More information can be found in the
“Practical hints” section (
page 250).

227
Operation
Engine compartment
Closing
Let the hood drop fr
om 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 gauge 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.

229
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 position 2 in the
starter switch:
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:
ENGINE OIL LEVEL - MASURING NOT POS-
SIBLE
Repeat the engine oil level check after
a short while.
See “Practical hints” (
page 262) if an en-
gine oil level indicator appears on the dis-
play when the engine is running.
More information on engine oil can be
found in the “Technical data” section
(
page 317).
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 transmission.Coolant 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.

230 OperationEngine compartment
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” (
page 321)
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 gauge indi-
cates 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.

257
Practical hints
What to do if …
Display
Possible cause
Suggested solution
B
COOLANT
CHECK LEVEL
The coolant level is too low.

Add coolant (
page 229).

If you have to add coolant frequently,
have the cooling system checked by
an authorized Mercedes-Benz Cen-
ter.
Warning!
G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You can be seriously burned.
!Do not ignore the low engine coolant
level warning. Extended driving with
the message and symbol displayed
may cause serious engine damage not
covered by the Mercedes-Benz Limited
Warranty.
Do not drive without sufficient amount
of coolant in the cooling system. The
engine will overheat, causing major en-
gine damage.

258 Practical hintsWhat to do if …
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 120°C.
Display
Possible cause
Suggested solution
Ï
COOLANT
STOP, ENGINE OFF!
The coolant is too hot.

Stop the vehicle and turn off the en-
gine.

Only start the engine again after the
message disappears. You could oth-
erwise damage the engine.
Warning!
G
Driving when your engine is badly overheat-
ed can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously burned.
Steam from an overheated engine can cause
serious burns and can occur just by opening
the engine hood. Stay away from the engine
if you see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until it
cools down.
!The engine should not be operated with
the coolant temperature above 248°F
(120°C). Doing so may cause serious
engine damage which is not covered by
the Mercedes-Benz Limited Warranty.

259
Practical hints
What to do if …
Display
Possible cause
Suggested solution
Ï
COOLANT
STOP, ENGINE OFF!
The poly-V-belt could be broken.

Stop immediately and check the
poly-V-belt.
If it is broken:

Do not continue to drive. Otherwise
the engine will overheat due to an in-
operative water pump which may re-
sult in damage to the engine. Notify
an authorized Mercedes-Benz
Center.
If it is intact:

Do not continue to drive the vehicle
with this message displayed. Doing
so could result in serious engine
damage that is not covered by the
Mercedes-Benz Limited Warranty.
COOLANT
VISIT WORKSHOP!
The cooling fan for the coolant is malfunc-
tioning.

Observe the coolant temperature
gauge.

Have the fan replaced as soon as
possible.