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

205 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 passenger
compartment near the engine hood
release.
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 il-
luminates for a brief period after
starting the engine.
The warning lamp reminds you to fasten seat
belts.

Fasten your seat belt.

206 Practical hintsWhat to do if …When the low engine oil level warning lamp
does not go out after starting the engine,
or comes on while the engine is running
and at operating temperature, the engine
oil level has dropped to approximately the
minimum mark on the dipstick.When this occurs, the warning lamp 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.Problem
Possible cause
Suggested solution
_
The red telescoping steering
column* warning lamp remains
lit after starting the engine.
The adjustable steering column is not locked
properly.

Lock the steering column
(page 34).
W
The yellow low windshield and
headlamp* washer system fluid
level warning lamp remains lit af-
ter starting the engine or lights
up while driving.
The fluid level has dropped to about
1/3 of
total reservoir capacity.

Add washer fluid (
page 184).
N
The yellow low engine oil level
warning lamp remains lit after
starting the engine or comes on
while driving.
The engine oil level has sunk to the minimum
level.

Check the engine oil level
(page 175) and add oil as required
(page 179).

If you must add engine oil frequently,
have the engine checked for possible
leaks.!The low engine oil level warning light
should not be ignored. Extended driv-
ing with the light illuminated could re-
sult in serious engine damage that is
not covered by the Mercedes-Benz
Limited Warranty.

207 Practical hints
What to do if …
Problem
Possible cause
Suggested solution
The fuel reserve and fuel cap placement
warning lamp:

lights up while driving
The fuel level has gone below the reserve
mark.

Refuel at the next gas station
(page 171).


blinks
The fuel cap is not closed tight.

Check the fuel cap.
A fuel system leak has been detected.

Have the fuel system checked as soon
as possible by an authorized
Mercedes-Benz Center
B
The yellow low engine coolant
level warning lamp remains lit af-
ter starting the engine or lights
up while driving.
The coolant level is too low.

Add coolant (
page 180).

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 light. Extended driving
with the light illuminated 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
engine damage.

208 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
#
The red charge indicator lamp
lights up while the engine is
running.
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-belts.
If one 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
authorized Mercedes-Benz Center.
Adjust driving to be consistent with
reduced braking responsiveness.

209 Practical hints
What to do if …
Problem
Possible cause
Suggested solution
2
The yellow brake pad wear indi-
cator lamp lights up while brak-
ing.
The brake pads have reached their wear limit.

Have the brake pads replaced as soon
as possible.
.
The yellow exterior lamp failure
indicator lamp lights up while
applying the brake and stays on
until the engine is turned off.
One of the brake lamps is malfunctioning.

Replace the bulb as soon as possible
(page 226).
.
The yellow exterior lamp failure
indicator lamp remains lit after
starting the engine or lights up
while driving.
One of the following lamps is malfunctioning:

parking lamp


tail lamp


brake lamp


low beam head lamp

Replace the bulb as soon as possible
(page 226).
!Brake pad thickness must be visually
checked by a qualified technician at the
intervals specified in the Service book-
let.
iAdditional lighting equipment, if not
properly installed (e.g. auxiliary head-
lamps etc.), could cause the failure in-
dicator monitoring unit to malfunction.
We therefore recommend that an au-
thorized Mercedes-Benz Center install
such equipment for you.
iIf an exterior lamp fails, the indicator
lamp will come on only when that lamp
is switched on.

251 Practical hints
Battery
Battery
The battery is located in the engine com-
partment on the right-hand side.
1Battery
2Positive terminal
3Negative terminal
Warning!
G
Failure to follow these instructions can re-
sult in severe injury or death.
Observe all safety instructions and precau-
tions when handling automotive batteries,
see “Battery” (
page 183).
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 steering lock. Other-
wise the alternator and other electronic
components could be severely dam-
aged.
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.

254 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 (12V). Jump start-
ing with a more powerful battery could
damage the vehicle‘s electrical system,
which will not be covered by the
Mercedes-Benz Limited Warranty.


Use only jumper cables with sufficient
cross-section and insulated terminal
clamps.


Always make sure the jumper cables
are not on or near pulleys, fans, or oth-
er 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.
Attempting to jump start a frozen battery
can result in it exploding, causing personal
injury.
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 us-
ing a battery quick charge unit.
If engine does not run after several un-
successful 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.

255 Practical hints
Jump starting
The battery is located on the right side of
the engine compartment.
Make sure the two vehicles do not
touch.

Turn off all electrical consumers.

Apply parking brake.

Shift gear selector lever to positionP
(manual transmission to Neutral).

Open the hood.

Connect positive terminals1 and2
of the batteries with the jumper cables.
Clamp cable to charged battery1
first.1Positive terminal of charged battery
2Positive terminal of discharged battery
3Negative terminal of discharged
battery
4Negative terminal of charged battery

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

Connect negative terminals3 and4
of the batteries with the jumper cables.
Clamp cable to charged battery4
first.

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

Remove the jumper cables first from
negative terminals3 and4 of the
batteries and then from positive
terminals1 and2.
You can now turn on the lights.

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.
!Never invert the terminal connections.
iVehicles with automatic transmission:
Do not tow-start vehicle.

279 Technical data
Fuels, coolants, lubricants etc.
Engine oils
Engine oils are specifically tested for their
suitability in our engines. Therefore, use
only engine oils recommended by
Mercedes-Benz. Information on approved
engine oils is available in the Factory Ap-
proved Service Products pamphlet, or at
your authorized Mercedes-Benz Center.Please follow FSS or Service Booklet rec-
ommendations for scheduled oil changes.
Failure to do so could result in engine dam-
age not covered by the Mercedes-Benz
Limited Warranty.
Engine oil additives
Do not blend oil additives with engine oil.
They may damage the engine.
Damage or malfunctions resulting from
blending oil additives are not covered by
the Mercedes-Benz Limited Warranty.Air conditioning refrigerant
R-134a (HFC) refrigerant and special
PAG lubricating oil is used in the air condi-
tioning system.Never use R-12 (CFC) or mineral-based
lubricating oil, otherwise damage to the
system will occur.
Brake fluid
During vehicle operation, the boiling point
of the brake fluid is continuously reduced
through the absorption of moisture from
the atmosphere. Under extremely strenu-
ous operating conditions, this moisture
content can lead to the formation of bub-
bles in the system, thus reducing the sys-
tem’s efficiency.
Therefore, the brake fluid must be re-
placed every two years, preferably in the
spring.
Only brake fluid approved by
Mercedes-Benz is recommended. Your au-
thorized Mercedes-Benz Center will pro-
vide you with additional information.
!Always check the oil filler cap
(page 171) for important informa-
tion pertaining to the engine oil need-
ing to meet a specific Mercedes-Benz
specification (e.g. MB 229.5). If such
information is printed on the oil filler
cap, only use an engine oil from the list
of approved engine oils in the Factory
Approved Service Products pamphlet
that meets the specification indicated
on the oil filler cap.
Using engine oils of other specification
may cause the FSS to incorrectly deter-
mine the next service interval and will
result in engine damage not covered by
the Mercedes-Benz Limited Warranty.

281 Technical data
Fuels, coolants, lubricants etc.
Damage or malfunctions resulting from
poor fuel quality or from blending specific
fuel additives are not covered by the
Mercedes-Benz Limited Warranty.Coolants
The engine coolant is a mixture of water
and anticorrosion / antifreeze, which pro-
vides:

Corrosion protection


Freeze protection


Boiling protection (by increasing the
boiling point)
The cooling system was filled at the factory
with a coolant providing freeze protection
to approximately -22°F (-30°C) and corro-
sion protection.
If the antifreeze mixture is effective to
-22°F (-30°C), the boiling point of the cool-
ant in the pressurized cooling system is
reached at approximately 266°F (130°C).The coolant solution must be used
year-round to provide the necessary corro-
sion protection and increase boil over-pro-
tection. Refer to Service Booklet for
replacement interval.
Coolant system design and coolant used
stipulate the replacement interval. The re-
placement interval published in the Ser-
vice Booklet is only applicable if MB 325.0
anticorrosion/antifreeze solution or other
Mercedes-Benz approved products of
equal specification (see Factory Approved
Service Products pamphlet) are used to re-
new the coolant concentration or bring it
back up to the proper level.
To provide important corrosion protection,
the solution must be at least 45% anticor-
rosion/antifreeze (equivalent to freeze
protection to approx. -22°F [-30°C]). If you
use a solution that is more than 55% anti-
corrosion/antifreeze (freeze protection to
approx. -49°F [-45°C]), the engine temper-
ature will increase due to the lower heat transfer capability of the solution. There-
fore, do not use more than this amount of
anticorrosion/antifreeze.
If the coolant level is low, water and MB
Anticorrosion /Antifreeze should be used
to bring it up to the proper level (have cool-
ing system checked for signs of leakage).
Please make sure the mixture is in accor-
dance with label instructions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you
are not sure about the water quality, con-
sult your authorized Mercedes-Benz
Center.