2008 MERCEDES-BENZ SLK350 check engine

351 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
USA only:
?
Canada only:
±
The yellow engine malfunction
indicator lamp comes on when
the engine is running.There is a malfunction in:

The fuel injection system

The ignition system

The emission control system

Systems which effect 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 pos-
sible 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 malfunc-
tions through the readout of diagnostic
trouble codes. It is located in the front left
area of the footwell near the hood release.
iSome states may by law require you to visit
a workshop as soon as the engine malfunction
indicator lamp comes on. Check local require-
ments.

352 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
vThe yellow ESP® warning lamp
comes on when the engine is
running.The ESP® has been switched off
with the ESP® switch or has been
switched off due to a malfunction.
Risk of accident!
When the ESP
® is switched off, it
will not stabilize the vehicle if the
system recognizes that the vehicle
starts to skid or that a wheel is
spinning.
The cruise control is deactivated
and cannot be switched on.
Switch the ESP® back on (page 89).
Exceptions: (
page 86).
If leaving the ESP® switched off, adapt your
speed and driving to the prevailing road,
weather and traffic conditions.
If the ESP
® cannot be switched back on:
Continue driving with added caution.
Observe additional messages that may appear
in the multifunction display (
page 363).
Have the system checked at an authorized
Mercedes-Benz Center as soon as possible.
The yellow ESP® warning lamp
flashes when the engine is running.The ESP® or traction control has
come into operation because of
detected traction loss in at least
one tire.
The cruise control is deactivated.When driving off, apply as little throttle as
possible.
While driving, ease up on the accelerator.
Adapt your speed and driving to the prevailing
road and weather conditions.
Do not deactivate the ESP®.
Exceptions: (
page 86).
Failure to follow these instructions increases the
risk of an accident.

355 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.

372 Practical hints
What to do if …
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).

373 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.

374 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
•Coolant
Stop, turn engine
off
.
The 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)

376 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
/Top Up Coolant
See Operator’s 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.

377 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
±Display Malfunction
Drive To WorkshopCertain electronic systems are un-
able to relay information to the con-
trol 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.
NCheck oil level
when next refueling
.
SLK 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.