check engine MERCEDES-BENZ CLK-CLASS 2004 Owner's Manual

314 Practical hintsWhat 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 impact emissions
Such malfunctions may result in excessive
emissions values and may switch the engine
to its Limp-Home Mode (emergency opera-
tion).

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 system.
It allows the accurate identification of
system malfunctions through the read-
out of diagnostic trouble codes. It is lo-
cated in the front left area of the
footwell next to the parking brake pedal.
The fuel cap is not closed tightly.

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.
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315 Practical hints
What to do if …?
Problem
Possible cause
Suggested solution
•
The red coolant warning lamp
comes on when the engine is
running.
There is insufficient coolant in the reservoir.

Add coolant to prevent engine from
overheating (
page 292).
If this warning lamp comes on frequently,
there is a leak in the cooling system.

Have the cooling system checked.
If the coolant level is correct, the electric ra-
diator fan may be broken.

If the coolant temperature is below
257 °F (125 °C), you can continue
driving to the nearest authorized
Mercedes-Benz Center.

Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.
•
The red coolant warning lamp
comes on while driving and you
hear a warning sound.
The coolant temperature has exceeded
257 °F (125 °C).

Stop as soon as possible and allow
the engine and coolant to cool down.
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 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 the
engine has cooled down.
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317 Practical hints
What to do if …?
Problem
Possible cause
Suggested solution
v
The yellow ESP warning lamp
flashes while driving.
The ESP or traction control has come into
operation because of detected traction loss
in at least one tire.
Distronic* is deactivated.

When driving off, apply as little throt-
tle as possible.

While driving, ease up on the acceler-
ator.

Adapt your speed and driving to the
prevailing road and weather condi-
tions.

Do not deactivate the ESP.
Exceptions: (
page 80).
Failure to follow these instructions in-
creases the risk of accidents.
A
The yellow fuel tank reserve
warning lamp comes on while
driving.
The fuel level has gone below the reserve
mark.

Refuel at the next gas station
(page 284).
C
The yellow roll bar warning lamp
comes on or flickers when the
engine is running.
The roll bar system is malfunctioning.

Release the roll bars manually.

Have the system checked at an autho-
rized Mercedes-Benz Center as soon
as possible.
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318 Practical hintsWhat to do if …?Problem
Possible cause
Suggested solution
<
The red seat belt non-usage
warning lamp illuminates briefly
after starting the engine.
The warning lamp reminds you to fasten seat
belts.

Fasten your seat belt.
1
The red SRS indicator lamp
comes on while driving.
There is a malfunction in the restraint sys-
tems. The airbags or emergency tensioning
device (ETD) could deploy unexpectedly or
fail to activate in an accident.

Drive with added caution to the near-
est authorized Mercedes-Benz Cen-
ter.
Warning!
G
In the event that a malfunction of the SRS is
indicated as outlined above, the SRS may
not be operational. For your safety, we
strongly recommend that you visit an autho-
rized Mercedes-Benz Center immediately to
have the system checked; otherwise the
SRS may not be activated when needed in
an accident, which could result in serious or
fatal injury, or it might deploy unexpectedly
and unnecessarily, which could result in an
accident and/or injury to you or to others.
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326 Practical hintsWhat to do if …?Symbol messagesDisplay symbol
Display message
Possible cause
Possible solution
#
Undervoltage
Charge battery
The battery has insufficient voltage.

Start the engine (
page 43).
Undervoltage
Switch off
consumers
The battery has insufficient voltage.

Turn off unnecessary electrical con-
sumers.
VISIT WORKSHOP!
The battery was charged with a battery
charger or jump started.

Have the battery checked at a service
station.
The battery is no longer charging.
Possible causes:

alternator malfunctioning


broken poly-V-belt

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:

Drive immediately to the nearest au-
thorized Mercedes-Benz Center. Ad-
just driving to be consistent with
reduced braking responsiveness.
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327 Practical hints
What to do if …?
Display symbol
Display message
Possible cause
Possible solution
2
Brake wear
Visit workshop
!
The brake pads have reached their wear
limit.

Have the brake pads replaced as soon
as possible.
;
(USA only)
!
(Canada only)
Parking brake
Release brake!
You are driving with the parking brake set.

Release the parking brake
(page 46).
;
(USA only)
3
(Canada only)
Brake fluid
Visit workshop!
There is insufficient brake fluid in the res-
ervoir.

Risk of accident! 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 this message displayed can re-
sult in an accident. Have your brake system
checked immediately. Don’t add brake fluid
before checking the brake system. Overfill-
ing the brake fluid reservoir can result in
spilling brake fluid on hot engine parts and
the brake fluid catching fire. You can be se-
riously 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.
!Brake pad thickness must be visually
checked by a qualified technician at the
intervals specified in the Service Book-
let.
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328 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause
Possible solution
?
Visit workshop!
There may be a malfunction in the

fuel injection system


ignition system


exhaust system


fuel system

Have the measuring system checked
by an authorized Mercedes-Benz Cen-
ter.
B
Coolant
Check level
The coolant level is too low.

Add coolant (
page 292).

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.
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330 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause
Possible 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 dis-
play.

Have the fan replaced as soon as pos-
sible.
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332 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause
Possible solution
:
USA only:Add 1 qt. engine oil
when next refuelingCanada only:Add 1 liter engine oil
when next refueling
The engine oil level is too low.

Add engine oil (
page 291) and check
the engine oil level (
page 289).
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 or drained off. Ob-
serve all legal requirements with re-
spect to its disposal.
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 (
page 291) and check
the engine oil level (
page 289).
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333 Practical hints
What to do if …?
When the message
Add 1 qt. engine oil
when next refueling
(Canada:
1 liter
)
appears while the engine is running and at
operating temperature, the engine oil level
has dropped to approximately the
minimum level.When this occurs, the warning will first
come on intermittently and then stay on if
the oil level drops further.
Visually check for oil leaks. If no obvious oil
leaks are noted, drive to the nearest ser-
vice station where the engine oil should be
topped to the required level with an ap-
proved oil.
Display symbol
Display message
Possible cause
Possible solution
:
Engine oil
Visit workshop!
It may be that there is water in the engine
oil.

Have the engine oil checked.
Engine oil level
Visit workshop!
The engine oil has dropped to a critical
level.

Check the engine oil level
(page 289) and add oil as required
(page 291).

If you must add engine oil frequently,
have the engine checked for possible
leaks.
The measuring system is malfunctioning.

Have the measuring system checked
by an authorized Mercedes-Benz
Center.!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.
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