check engine MERCEDES-BENZ C320 2003 W203 Owner's Guide

266 Practical hintsWhat to do if …Display
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Suggested solution
B
COOLANT
CHECK LEVEL!
The coolant level is too low.

Add coolant (
page 238).

If you have to add coolant frequently,
have the cooling system checked by
an authorized Mercedes-Benz Center.
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.

268 Practical hintsWhat to do if …Display
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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
inoperative water pump which may
result 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
malfunctioning.

Observe the coolant temperature
display.

Have the fan replaced as soon as
possible.

269 Practical hints
What to do if …
ESP
ESP
NOT AVAILABLE!
The ESP is deactivated because of a
malfunction or interrupted power supply.
The ABS might not be operational.

With vehicle stationary and the engine
running, turn the steering wheel
completely to the left and then to the
right to synchronize the ESP.
If the ESP message does not go out:

Continue driving with added caution.

Visit an authorized Mercedes-Benz
Center as soon as possible.
Failure to follow these instructions
increases the risk of accident.
The self-diagnosis has not been
completed.
The display will clear itself after driving a
short distance at more than 12 mph
(20 km/h).
The charging voltage has fallen below ten
volts and the ESP has switched off.

When the voltage is above this value
again, the ESP is operational again.

If necessary, have the generator and
battery checked.
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Possible cause
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270 Practical hintsWhat to do if …ESP
ESP
VISIT WORKSHOP!
The ESP is deactivated because of a
malfunction.

Continue driving with added caution.

Visit an authorized Mercedes-Benz
Center as soon as possible.
Failure to follow these instructions
increases the risk of accident.
DISPLAY DEFECTIVE
VISIT WORKSHOP!
The ESP or the ESP display is
malfunctioning.

Continue driving with added caution.

Visit an authorized Mercedes-Benz
Center as soon as possible.
Failure to follow these instructions
increases the risk of accident.
:
ENGINE OIL LEVEL
STOP, ENGINE OFF!
There is no oil in the engine. There is a
danger of engine damage.

Carefully bring the vehicle to a halt as
soon as possible.

Turn off the engine.

Add engine oil.
ENGINE OIL LEVEL
CHECK LEVEL!
The engine oil level is too low.

Check the engine oil level
(page 236) and add oil as required.
ENGINE OIL LEVEL
REDUCE OIL LEVEL!
You have added too much engine oil.
There is a risk of damaging the engine or
the catalytic converter.

Have oil siphoned. Observe all legal
requirements with respect to its
disposal.
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Suggested solution

271 Practical hints
What to do if …
When the
ENGINE OIL LEVEL – CHECK
LEVEL!
message appears while the engine
is running and at operating temperature,
the engine oil level has dropped to approx-
imately the minimum mark on the dipstick.
When this occurs, the warning will first
come on intermittently and then stay on if
the oil level drops further.
If no oil leaks are noted, continue to drive
to the nearest service station where the
engine oil should be topped to the “full”
mark on the dipstick with an approved oil.
:
ENGINE OIL
VISIT WORKSHOP!
The engine oil has dropped to a critical
level.

Check the engine oil level
(page 236) and add oil as required.

If you must add engine oil frequently,
have the engine checked for possible
leaks.
There is water in the oil.

Have the oil checked.
ENGINE OIL LEVEL
VISIT WORKSHOP!
The measuring system is malfunctioning.

Have the measuring system checked
by an authorized Mercedes-Benz
Center.
Display
Possible cause
Suggested solution
!The engine oil level warnings should
not be ignored. Extended driving with
the symbol displayed could result in
serious engine damage that is not
covered by the Mercedes-Benz Limited
Warranty.

275 Practical hints
What to do if …
.
TAIL LAMP, L
CHECK LAMPS!

SUBSTITUTE LAMP ON!

The left tail lamp is malfunctioning.
A backup bulb is being used.

Visit an authorized Mercedes-Benz
Center as soon as possible.
TAIL LAMP, R
CHECK LAMPS!

SUBSTITUTE LAMP ON!

The right tail lamp is malfunctioning.
A backup bulb is being used.

Visit an authorized Mercedes-Benz
Center as soon as possible.
SIDE MARKER LAMP, LF
CHECK LAMPS!

SUBSTITUTE LAMP ON!

The left parking lamps are
malfunctioning. A backup bulb is being
used.

Visit an authorized Mercedes-Benz
Center as soon as possible.
SIDE MARKER LAMP, RF
CHECK LAMPS!

SUBSTITUTE LAMP ON!

The right parking lamps are
malfunctioning. A backup bulb is being
used.

Visit an authorized Mercedes-Benz
Center as soon as possible.
AUTOM. LIGHT ON
REMOVE KEY!
Key in the starter switch position1 or2.

Remove key from the starter switch.
LIGHTS
TURN OFF LAMPS!
This display appears if the driver’s door is
opened with the engine shut off and no
key in the starter switch.

Insert key in the starter switch.

Switch off lights.
<
SEAT BELT SYSTEM
VISIT WORKSHOP!
The seat belt system is malfunctioning.

Visit an authorized Mercedes-Benz
Center as soon as possible.
DRIVER’S SEAT BELT
FASTEN SEAT BELT!
The display reminds you and your
passengers to fasten seat belts.

Fasten the seat belts.
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Possible cause
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278 Practical hintsWhat to do if …Display
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#
UNDERVOLTAGE
ENGINE ON!
The battery has insufficient voltage and
can no longer supply the convenience
functions such as seat heater*.

Start the engine (
page 44).
UNDERVOLTAGE
SWITCH CONSUMERS OFF!
The battery is malfunctioning.

Have the battery checked at a service
station.
G
VISIT WORKSHOP!
DISPLAY DEFECTIVE
The instrument cluster display is
malfunctioning.

Continue driving with added caution.

Visit an authorized Mercedes-Benz
Center as soon as possible.
±
VISIT WORKSHOP!
DISPLAY DEFECTIVE
Certain electronic systems are unable to
relay information to the control system.
The following systems may have failed:

Coolant temperature display


Tachometer


Cruise control display

Have the electronic systems checked
by an authorized Mercedes-Benz
Center (
page 259).
W
WASHER FLUID
CHECK LEVEL!
The fluid level has dropped to about
1/3
of total reservoir capacity.
Add washer fluid (
page 241).

303 Practical hints
Battery
Battery
The battery is located in the engine com-
partment on the right hand side.
Removal of filter box:
Release the three clamps1.

Remove filter box.
Installation of filter box:

Insert filter box properly.

Secure it with the three clamps1.
Warning!
G
Failure to follow these instructions can re-
sult in severe injury or death.
Never lean over batteries while connecting,
you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking etc.
!Never loosen or detach battery termi-
nal clamps while the engine is running
or the key is in the starter switch. Oth-
erwise the alternator and other elec-
tronic components could be severely
damaged.
Have the battery checked regularly by
an authorized Mercedes-Benz Center.
Refer to Service Booklet for mainte-
nance intervals or contact your autho-
rized Mercedes-Benz Center for further
information.Warning!
G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof battery only to avoid the risk
of acid burns in the event of an accident.

306 Practical hintsJump starting
Jump starting
If the battery is discharged, the engine can
be started with jumper cables and the bat-
tery of another vehicle. Observe the follow-
ing:

Jump starting should only be performed
when the engine and catalytic convert-
er are cold.


Do not start the engine if the battery is
frozen. Let the battery thaw out first.


Only jump start from batteries with the
same voltage rating (12 V). Jump
starting with a more powerful battery
could damage the vehicle’s electrical
system, which will not be covered by
the Mercedes-Benz Limited Warranty.


Only use jumper cables with sufficient
cross-section and insulated terminal
clamps.


Always make sure that the jumper
cables are not on or near pulleys, fans,
or other parts that move when an
engine is started or running.
Warning!
G
Failure to follow these directions will cause
damage to the electronic components, and
can lead to a battery explosion and severe
injury or death.
Never lean over batteries while connecting
or jump starting, you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water, and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and very explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking etc.
Read all instructions before proceeding.
!Jump starting may only be performed
on the battery installed in the engine
compartment.
Avoid repeated and lengthy starting at-
tempts.
Do not attempt to start the engine
using a battery quick charge unit.
If engine does not run after several
unsuccessful starting attempts, have it
checked at the nearest authorized
Mercedes-Benz Center.
Excessive unburned fuel generated by
repeated failed starting attempts may
damage the catalytic converter and
may present a fire risk.
Make sure the jumper cables do not
have loose or missing insulation.
Make sure the cable clamps do not
touch any other metal part while the
other end is still attached to a battery.

307 Practical hints
Jump starting
The battery is located in the engine
compartment on the right hand side. The
terminals for jump starting are located in
front of the battery.
Make sure that the two vehicles do not
touch.

Turn off all electrical consumers.

Apply parking brake.

Shift selector lever to positionP (man-
ual transmission to Neutral).1Positive terminal of charged battery
2Positive under hood terminal in front of
discharged battery
3Negative terminal of charged battery
4Negative under hood terminal in front
of discharged battery

Connect positive terminal1 of the
charged battery with the under hood
terminal2 in front of the discharged
battery with the jumper cables. Clamp
cable to charged battery1 first.

Start engine of the vehicle with the
charged battery and run at idle speed.

Connect negative terminal3 of the
charged battery with the under hood
terminal4 of the discharged battery
with the jumper cables. Clamp cable to
charged battery3 first.

Start the engine of the disabled vehi-
cle.
Now you can again turn on the electrical
consumers. Do not turn on the lights under
any circumstances.

Remove the jumper cables first from
negative terminals3 and4 and then
from positive terminals1 and2.

Have the battery checked at the near-
est authorized Mercedes-Benz Center.
Warning!
G
Keep flames or sparks away from battery.
Do not smoke.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 240).
!Vehicles with automatic transmission
and/or 4MATIC*:
Do not tow-start the vehicle.