Page 385 of 522

384 Practical hintsWhat to do if …Problem
Possible cause/consequence
Suggested solution
ú
(USA only)
±
(Canada only)
The yellow engine mal-
function indicator lamp
comes on while driving.
There may be a malfunction in the
fuel management system
ignition system (gasoline engine)
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 possi-
ble 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 trou-
ble codes. It is located in the front left area
of the footwell next to the parking brake.
i
Some states may by law require you to visit
a workshop immediately as soon as the engine
malfunction indicator lamp comes on. Check lo-
cal requirements.
Page 386 of 522
385 Practical hints
What to do if …
Problem
Possible cause/consequence
Suggested solution
ú
(USA only)
±
(Canada only)
The yellow engine mal-
function indicator lamp
comes on while driving.
A loss of pressure has been detected in the
fuel system. The fuel cap may not be closed
properly or the fuel system may be leaky.
Check the fuel cap.
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.
Your fuel tank is empty.
After refuelling 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.
Page 387 of 522

386 Practical hintsWhat to do if …Problem
Possible cause/consequence
Suggested solution
D
The red coolant temperature
warning lamp comes on when
the engine is running.
There is insufficient coolant in the reservoir.
If this warning lamp comes on frequently,
there is a leak in the cooling system.
If the coolant level is correct, the electric ra-
diator fan may be broken.
Immediately add coolant to prevent
engine from overheating
(page 330).
Have the cooling system checked.
If the coolant temperature is below
248°F (120°C), you can continue
driving to the nearest authorized
Mercedes-Benz Center.
Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.
The red coolant temperature
warning lamp comes on while
driving and you hear a warning
sound.
The coolant temperature has exceeded
248°F (120°C).
Stop as soon as possible in a safe lo-
cation and allow the engine and cool-
ant to cool down.
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 which can occur just by open-
ing the engine hood. Stay away from the en-
gine 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.
Page 388 of 522
387 Practical hints
What to do if …
Problem
Possible cause/consequence
Suggested solution
l
Only vehicles with Distronic*:
The red distance warning lamp
comes on while driving.
You are too close to the vehicle in front of you
to maintain selected speed.
Apply the brakes immediately to in-
crease the following distance.
Only vehicles with Distronic*:
The red distance warning lamp
comes on while driving and you
hear a warning chime sound.
You are gaining too rapidly on the vehicle
ahead of you.
The distance warning system has recog-
nized a stationary obstacle on your prob-
able line of travel.
Apply the brakes immediately.
Carefully observe the traffic situation.
You may need to brake or maneuver
to avoid hitting an obstacle.
A
The yellow fuel tank reserve
warning lamp comes on while
driving.
The fuel level has gone below the reserve
mark.
Refuel at the next gas station
(page 321).
Page 389 of 522

388 Practical hintsWhat to do if …Problem
Possible cause/consequence
Suggested solution
<
The red seat belt telltale comes
on for a maximum of 6 seconds
after starting the engine.
The seat belt telltale reminds you and your
passengers 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
engine.
You hear a warning chime for a
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.
The red seat belt telltale comes
on while the vehicle is standing
still and the engine is running or
during driving.
You and/or your front passenger have for-
gotten to fasten your seat belts.
Fasten your seat belts.
The seat belt telltale goes out.
There are items placed on the front passen-
ger seat and therefore the system senses the
front passenger seat as being occupied.
Remove the items from the front pas-
senger seat and put them in a safe
place.
The seat belt telltale goes out.
Page 390 of 522

389 Practical hints
What to do if …
Problem
Possible cause/consequence
Suggested solution
<
During driving the red seat belt
telltale flashes and you addi-
tionally hear an intermittent
warning chime with increasing
intensity.
The vehicle’s speed once exceeded 15 mph
(25 km/h) and you and/or your front pas-
senger have forgotten to fasten your seat
belts.
Fasten your seat belts.
The seat belt telltale goes out and the
warning chime stops sounding.
There are items placed on the front passen-
ger seat and therefore the system senses the
front passenger seat as being occupied.
Remove the items from the front pas-
senger seat and put them in a safe
place.
The seat belt telltale goes out and the
warning chime stops sounding.
i
After 60 seconds with an unfastened seat
belt the warning chime stops sounding and the
seat belt telltale illuminates continuously. The
seat belt telltale will only go out if both, the driver
and front passenger’s seat belt are fastened, or
the vehicle is standing still and a front door is
opened.
Page 391 of 522
390 Practical hintsWhat to do if …Problem
Possible cause/consequence
Suggested solution
1
The red SRS indicator lamp
comes on while driving.
There is a malfunction in the restraint sys-
tems. The air bags or Emergency Tensioning
Devices (ETDs) could deploy unexpectedly or
fail to activate in an accident.
Drive with added caution to the near-
est authorized Mercedes-Benz Cen-
ter.
Warning!
G
In the event a malfunction of the SRS is indi-
cated as outlined above, the SRS may not be
operational. For your safety, we strongly
recommend that you visit an authorized
Mercedes-Benz Center immediately to have
the system checked; otherwise the SRS may
not be activated when needed in an acci-
dent, 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 392 of 522
391 Practical hints
What to do if …
Problem
Possible cause/consequence
Suggested solution
H
Low tire pressure telltale for the
Advanced TPMS* illuminates
continuously.
The Advanced TPMS* detects a loss of
pressure in at least one tire.
Carefully bring the vehicle to a halt,
avoiding abrupt steering and braking
maneuvers. Observe the traffic situation
around you.
Read and observe messages in the mul-
tifunction display.
If the tire inflation pressure in the respec-
tive tire(s) has (have) been corrected, the
low tire pressure telltale goes out after few
minutes driving.