2007 MERCEDES-BENZ SLK CLASS engine

351 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
on for a maximum of 6 seconds
after starting the engine.The seat belt telltale reminds you and your
passenger to fasten your seat belts before
driving off.Fasten your seat belts.
Regardless of whether the seat belts
are fastened or not, the seat belt tell-
tale always comes on and remains lit
for 6 seconds after starting the en-
gine.
maximum of 6 seconds after
starting the engine.You have forgotten to fasten your seat belt.Fasten your seat belt.
The warning chime stops sounding.
on while the vehicle is standing
still and the engine is running or
during driving.You and/or your passenger have forgotten to
fasten your seat belts.Fasten your seat belts.
The seat belt telltale goes out.
There are items placed on the passenger seat
and therefore the system senses the passen-
ger seat as being occupied.Remove the items from the passenger
seat and put them in a safe place.
The seat belt telltale goes out.

353 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
4The yellow fuel reserve warning lamp
flashes after starting the engine.The fuel cap is not closed properly.Close the fuel cap.
The yellow fuel reserve warning lamp
comes on when the engine is
running.
Additionally you see the message
Reserve fuel in the multifunction
display.
The fuel level has gone below the
reserve mark.Refuel at the next gas station (page 291).
After refueling you will see the message
1 message in the multifunction display.
Press reset buttonJto confirm the
message (
page 26).
1The red SRS indicator lamp comes
on when the engine is running.There is a malfunction in the
restraint systems. The air bags or
emergency tensioning devices
(ETDs) could deploy unexpectedly or
fail to deploy in an accident.Drive with added caution to the nearest
authorized Mercedes-Benz Center.
Warning!G
In the event a malfunction of the SRS is
indicated as outlined above, the SRS may
not be operational. For your safety, we
strongly recommend that you contact an
authorized Mercedes-Benz Center
immediately to have the system checked;
otherwise the SRS may not be deployed
when needed in an accident, which could
result in serious or fatal injury, or it might
deploy unexpectedly and unnecessarily
which could also result in an accident
and/or injury to you or to others.

366 Practical hints
What to do if …
Symbol messages
Display symbolDisplay messagePossible cause/consequencePossible solution
#The battery is no longer charging.
Possible causes:

Alternator malfunctioning

Broken poly-V-belt
Do not forget that the brake system
requires electrical energy and may
be operating with restricted capa-
bility. Considerably greater brake
pedal force is required and the stop-
ping distance is increased.
Stop the vehicle immediately in a safe loca-
tion 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. Contact
an authorized Mercedes-Benz Center.
If it is in order:
Contact an Mercedes-Benz Center
immediately. Adjust driving to be consis-
tent with reduced braking responsive-
ness.
USA only:
;
Canada only:
!
Release
parking brakeYou are driving with the parking
brake set.Release the parking brake (page 53).

367 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
USA only:
;
Canada only:
3
Check
brake fluid levelThere is insufficient brake fluid in
the reservoir.Risk of accident!
Stop the vehicle in a safe location or as soon as
it is safe to do so.
Turn off the engine.
Apply the parking brake (page 59).
Do not drive any further.
Contact an authorized Mercedes-Benz Center.
Do not add brake fluid! This will not solve the
problem.
2Brake wearThe brake pads have reached their
wear limit.Have the brake pads replaced as soon as
possible.
Warning!G
Driving with the message Check brake
fluid level
displayed can result in an
accident. Have your brake system checked
immediately. Do not add brake fluid before
checking the brake system.
Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot engine
parts and the brake fluid catching fire. You
can be seriously 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 Maintenance Booklet.

368 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
•Coolant
Stop, turn engine
offThe coolant is too hot.
Among other possible causes,
the poly-V-belt could be broken.Stop the vehicle in a safe location or as soon as it is
safe to do so.
Turn off the engine.
Apply the parking brake (page 59).
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. Contact an
authorized Mercedes-Benz Center.
If it is intact:
Wait for the message to disappear before restarting
the engine.
Doing otherwise could result in serious engine
damage that is not covered by the Mercedes-Benz
Limited Warranty.
(Continued on next page)

369 Practical hints
What to do if …
During severe operating conditions, e.g.
stop-and-go traffic, the coolant tempera-
ture may rise close to 248°F (120°C).
Display symbolDisplay messagePossible cause/consequencePossible solution
Observe the coolant temperature display
(
page 127).
If the temperature rises again:
Contact an authorized Mercedes-Benz
Center immediately.
Warning!G
Driving when your engine is overheated 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.

370 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
•The cooling fan for the coolant is
malfunctioning.Observe the coolant temperature display
(
page 127).
If the coolant temperature is below 120°C,
you may continue driving to the nearest
specialist workshop.
Avoid heavy loads on the engine (e.g. by
driving uphill) as well as stop-and-go traffic.
Have the fan replaced as soon as possible.
/Top up coolant
See Oper. ManualThe coolant level is too low.Add coolant (page 300).
Comply with all warnings while doing so.
If you have to add coolant frequently,
have the cooling system checked by an au-
thorized 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 could 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 engine
damage.

372 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
NCheck oil level
when next refuelingSLK 280 and SLK 350 only:
The engine oil level has dropped to
a critical level.Check the engine oil level (page 296) and
add engine oil as required (
page 299).
If you must add engine oil frequently, have
the engine checked for possible leaks.
USA only:
Add 1 qt. engine oil
when next refueling
Canada only:
Add 1 liter engine oil
when next refueling
SLK 55 AMG only:
The engine oil level is too low.Add engine oil (page 299) and check the
engine oil level (
page 296).
Cannot measure
motor oil levelSLK 55 AMG only:
The measuring system is malfunc-
tioning.Have the measuring system checked by an
authorized Mercedes-Benz Center.