Page 364 of 481

363 Practical hints
What to do if …
Problem
Possible cause/consequence
Suggested solution
;
3
(USA only)
(Canada only)
The red brake warning
lamp comes on while driv-
ing and you hear a warning
sound.
You are driving with the parking brake
set.
Release the parking brake
(page 52).
The red brake warning
lamp comes on while driv-
ing.
There is insufficient brake fluid in the
reservoir.
Risk of accident! Carefully 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 the brake warning lamp illumi-
nated can result in an accident. Have your
brake system checked immediately if the
brake warning lamp stays on. 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.
Page 365 of 481

364 Practical hintsWhat to do if …Problem
Possible cause/consequence
Suggested solution
?
±
(USA only)
(Canada only)
The yellow 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 ex-
cessive 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 system. It allows the accu-
rate identification of system malfunctions
through the readout of diagnostic trouble
cod es . It is l oc ate d i n the f ront l ef t a rea of the
footwell near the hood release.
Your fuel tank is empty.
After refueling start, turn off and restart the
engine three or four times in succession.
The limp-home mode is canceled. You do not
need to have your vehicle checked.
Additionally you see
the message
Check
gas cap
See Operator’s
Manual
in the multi-
function display.
A loss of pressure has been detect-
ed in the fuel system. The fuel cap
may not be closed properly or the
fuel system may be leaking.
Check the fuel cap (
page 304).
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked by an autho-
rized Mercedes-Benz Center.
Page 367 of 481

366 Practical hintsWhat to do if …4
The yellow fuel reserve warning lamp
flashes after starting the engine.
The fuel cap is not closed properly.
Close the fuel cap.
<
The red seat belt telltale comes on
after starting the engine with all
doors closed.
The seat belt telltale reminds you
and your passenger to fasten your
seat belts before driving off.
Fasten your seat belts (
page 71).
The red seat belt telltale flashes and
you additionally hear an intermittent
warning signal with increasing inten-
sity for a maximum of 60 seconds
when the vehicle’s speed exceeds
15 mph (25 km/h).
You and/or your passenger have
forgotten to fasten your seat belts.
There are items placed on the pas-
senger seat and therefore the sys-
tem senses the passenger seat as
being occupied.
Fasten your seat belts (
page 71).
Remove the items from the passenger seat
and put them in a safe place.
1
The red SRS indicator lamp comes
on while driving.
There is a malfunction in the re-
straint 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 au-
thorized Mercedes-Benz Center.
Problem
Possible cause/consequence
Suggested solution
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
authorized Mercedes-Benz Center immedi-
ately 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 also result in an accident and/or
injury to you or to others.
Page 376 of 481

375 Practical hints
What to do if …
Display symbol
Display message
Possible cause/consequence
Possible solution
USA only:;Canada only:!
Release
parking brake
You are driving with the parking
brake set.
Release parking brake (
page 52).
USA only:;Canada only:3
Brake fluid
Visit workshop
There is insufficient brake fluid in
the reservoir.
Risk of accident! Stop the vehicle and notify
an authorized Mercedes-Benz Center. Do
not add brake fluid! This will not solve the
problem.
2
Brake wear
Visit workshop
The brake pads have reached their
wear limit.
Have the brake pads replaced as soon as
possible.
Warning!
G
Driving with the message
Brake fluid
Visit workshop
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 re-
sult 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.
Page 377 of 481

376 Practical hintsWhat 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/conse-
quence
Possible solution
Ï
Coolant
Stop, engine off
The poly-V-belt could be
broken.
Stop the vehicle and immediately turn off the engine.
Check the poly-V-belt (
page 437).
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 128).
!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.
Page 378 of 481

377 Practical hints
What to do if …
Display symbol
Display message
Possible cause/consequence
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 313).
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.
Page 380 of 481

379 Practical hints
What 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 280,
SLK 350) appears while the engine is run-
ning and at operating temperature, the en-
gine 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/consequence
Possible solution
N
Check 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 308) and
add engine oil as required (page 312).
If you must add engine oil frequently, have
the engine checked for possible leaks.
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 312) and check the
engine oil level (page 308).
!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.
Page 381 of 481
380 Practical hintsWhat to do if …Display symbol
Display message
Possible cause/consequence
Possible solution
N
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 312) and check the
engine oil level (page 308).
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.