2005 MERCEDES-BENZ SLK CLASS check engine

357 Practical hints
What to do if …
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).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 (
page 411).
If it is broken:

Do not continue to drive. Otherwise the engine will overheat
due to an inoperative water pump which may result in dam-
age to the engine. Notify an authorized Mercedes-Benz
Center.
If it is in order:

Do not continue to drive the vehicle with this message dis-
played. Doing so could result in serious engine damage that
is not covered by the Mercedes-Benz Limited Warranty.
Drive immediately to the nearest authorized
Mercedes-Benz Center.

Observe the coolant temperature display (
page 122).
!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.

358 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
Ï
Coolant
Stop, engine off
The coolant is too hot.

Stop the vehicle and turn off the engine.

Only start the engine again after the mes-
sage disappears. You could otherwise dam-
age the engine.
/
Coolant
Check level
The coolant level is too low.

Add coolant (
page 293).

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

360 Practical hintsWhat to do if …When the message
Add 1 qt.
(Canada:
1 liter
) engine oil when next
refueling (SLK 55 AMG) or
Check oil
level when next refueling (SLK 350)
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 specified in the Factory
Approved Service Products pamphlet.
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
SLK 55 AMG only:
The engine oil level is too low.

Add engine oil (
page 292) and check the
engine oil level (page 288).
Check oil level
when next refueling
SLK 350 only:
The engine oil level has dropped to
a critical level.

Check the engine oil level (
page 288) and
add engine oil as required (page 292).

If you must add engine oil frequently, have
the engine checked for possible leaks.
!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.

361 Practical hints
What to do if …
Display symbol
Display message
Possible cause
Possible solution
:
Engine oil level
Stop, engine off
SLK 55 AMG only:
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 292) and check the
engine oil level (page 288).
Engine oil level
Visit workshop
SLK 55 AMG only:
The measuring system is malfunc-
tioning.

Have the measuring system checked by an
authorized Mercedes-Benz Center.
Engine oil level
Reduce oil level
SLK 55 AMG only:
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.
Observe all legal requirements with respect
to its disposal.
Engine oil
Visit workshop
SLK 55 AMG only:
There may be water in the engine
oil.

Have the engine oil checked.

396 Practical hintsBatteryThe battery is located in the engine com-
partment on the right-hand side below the
windshield washer fluid reservoir.
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 294).
Never lean over batteries while connecting
them, as you could otherwise be injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come into contact with
eyes, skin or clothing. In case it does, imme-
diately 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.
Warning!
G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof batteries only to avoid the
risk of acid burns in the event of an acci-
dent.!Never loosen or detach battery termi-
nal clamps while the engine is running
or the SmartKey is in the starter switch.
Otherwise the alternator and other
electronic components could be se-
verely damaged.
Have the battery checked regularly by
an authorized Mercedes-Benz Center.
Refer to Maintenance Booklet for main-
tenance intervals or contact an autho-
rized Mercedes-Benz Center for further
information.

399 Practical hints
Jump 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.


Only use 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, as you could otherwise be
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.
!Avoid repeated and lengthy starting at-
tempts.
Do not attempt to start the engine us-
ing a battery quick charge unit.
If the 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.

400 Practical hintsJump starting
Make sure the two vehicles do not
touch.

Switch off all electrical consumers.

Apply parking brake.

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

Open the hood (
page 287).

Remove the cover from positive under
hood terminal2 in front of discharged
battery.1Positive terminal of charged battery
2Positive under hood terminal in front of
discharged battery
3Negative under hood terminal in front
of discharged battery
4Negative terminal of charged battery

Connect positive terminal1 of the
charged battery with positive under
hood terminal2 in front of the dis-
charged battery with one jumper cable.
Clamp the cable to positive terminal1
of the charged battery first.

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

Connect negative terminal4 of the
charged battery with negative under
hood terminal3 in front of the dis-
charged battery with the second jump-
er cable. Clamp the cable to negative
terminal4 of the charged battery
first.

Start the engine of the disabled vehi-
cle.
You can now switch on the electrical con-
sumers. Do not switch on the lights under
any circumstances.

Remove the jumper cables first from
negative terminals3 and4 and then
from positive terminals2 and1.
You can now switch 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
(page 294).
!Never invert the terminal connections.
iVehicles with automatic transmission*:
Do not tow-start vehicle.

427 Technical data
Fuels, coolants, lubricants, etc.
If the coolant level is low, water and
MB Anticorrosion/Antifreeze should be
used to bring it up to the proper level (have
cooling system checked for signs of leak-
age). Please make sure the mixture is in
accordance 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 an authorized Mercedes-Benz Center.Anticorrosion/antifreeze
Your vehicle contains a number of alumi-
num parts. The use of aluminum compo-
nents in motor vehicle engines
necessitates that anticorrosion/antifreeze
coolant used in such engines be specifical-
ly formulated to protect the aluminum
parts. (Failure to use such anticorro-
sion/antifreeze coolant will result in a
significantly shortened service life.)
Therefore, the following product is strongly
recommended for use in your vehicle:
Mercedes-Benz 325.0
anticorrosion/antifreeze agent.Before the start of the winter season (or
once a year in hot southern regions), you
should have the anticorrosion/antifreeze
concentration checked. The coolant is also
regularly checked each time you bring your
vehicle to an authorized Mercedes-Benz
Center for service.