Page 572 of 723
569 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
;
(USA only)
3
(Canada only)
The red brake warning
lamp comes on while the
engine is running and an
acoustic warning sounds.There is insufficient brake fluid in the reser-
voir.Risk of accident!
Carefully stop the vehicle in a safe loca-
tion or as soon as it is safe to do so.
Engage the electronic parking brake
(
page 637).
Contact 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 en-
gine 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.
ProCarManuals.com
Page 573 of 723
570 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
±The yellow engine malfunc-
tion 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 excessive
emissions values and may switch the en-
gine to its limp-home (emergency opera-
tion) 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 accurate identification of
system malfunctions through the read-
out of diagnostic trouble codes. It is lo-
cated in the front left area of the
footwell.
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.
ProCarManuals.com
Page 574 of 723
571 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
±The yellow engine malfunc-
tion 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 au-
thorized Mercedes-Benz Center.
Your fuel tank is empty.After refueling, start, turn off, and re-
start the engine three or four times in
succession.
The limp-home mode is canceled. You do
not need to have your vehicle checked.
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Page 576 of 723
573 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
vThe yellow ESP® warning lamp
comes on while the engine is
running.The ESP® is deactivated.
Risk of accident!
Adapt your speed and driving to the prevail-
ing road, weather, and traffic conditions.Switch the ESP® back on (page 69).
Exceptions: (
page 71).
If the ESP
® cannot be switched back on:
Have the system checked at an autho-
rized Mercedes-Benz Center as soon as
possible.
ESP® is switched off due to a malfunction.
Risk of accident!
Adapt your speed and driving to the prevail-
ing road, weather, and traffic conditions.Continue driving with added caution.
Read and observe messages in the mul-
tifunction display (
page 580).
Have the system checked at an autho-
rized Mercedes-Benz Center as soon as
possible.
The yellow fuel tank reserve warning lamp
in the fuel gauge comes on while driving.The fuel level has gone below the reserve
mark.Refuel at the next gas station
(
page 509).
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 telltale al-
ways comes on and remains lit for
6 seconds after starting the engine.
ProCarManuals.com
Page 577 of 723
574 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
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 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.
telltale flashes and you addition-
ally 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.
iAfter 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 arefastened, or the vehicle is standing still and a
front door is opened.
ProCarManuals.com
Page 578 of 723
575 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
=The red SRS indicator lamp
comes on while the engine is
running.There is a malfunction in the supplemental
restraint systems. The air bags or emergen-
cy 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 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 contact an au-
thorized Mercedes-Benz Center immediate-
ly 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 unexpect-
edly and unnecessarily which could result in
an accident and/or injury to you or to
others.
ProCarManuals.com
Page 586 of 723
583 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
DISTRONIC PLUS
currently unavailable
See Oper. ManualDISTRONIC Plus* is switched off and is
temporarily unavailable.
DISTRONIC Plus* is deactivated if:
the DISTRONIC Plus* cover in the radia-
tor grille is dirty
the radar sensors* do not sense any
other vehicles or objects, i.e. road sign
or similar to this, for a long time
the system is overheated
its function is impaired as a result of
heavy precipitation or fog
the battery voltage is insufficient
Clean the DISTRONIC Plus* cover in the radiator grille
(
page 558).
Restart the vehicle.
Try activating DISTRONIC Plus* again later.
Wait until the system cools down or the battery recovers.
DISTRONIC Plus* will be operational again without you needing to
restart the engine if:
the dirt (e.g. slush) loosens while you are driving
the system detects that the sensors* are fully available again
the message in the multifunction display disappears
DISTRONIC Plus* is switched off because
the radar sensor system* is temporarily in-
operative due to electromagnetic interfer-
ence near television and radio transmitter
stations, toll stations, speed measuring sys-
tems, etc.Wait until the message in the multifunction display disappears.
ProCarManuals.com
Page 594 of 723
591 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Shift to P or N
to start engineYou have attempted to start the engine
while the automatic transmission was set to
position R or D.Shift the automatic transmission to P or N (page 389).
Tire pressure monitor
inoperativeThe Advanced TPMS or a wheel sensor is
malfunctioning.Have the Advanced TPMS checked by an authorized
Mercedes-Benz Center.
Tire pressure monitor
inoperative
No wheel sensorsThe Advanced TPMS is deactivated because
wheels without proper sensors were in-
stalled.Have the wheel sensors installed by an authorized
Mercedes-Benz Center.
As soon as all wheels with sensors have been mounted, the
Advanced TPMS is switched back on after driving for several
minutes.
Tire pressure monitor
currently unavailableThe Advanced TPMS is unable to monitor
the tire inflation pressure due to:
a nearby radio interference source
the on-board voltage is too low
excessive wheel sensor temperatures
As soon as the causes for the malfunction are no longer present,
the Advanced TPMS automatically becomes active again after a
few minutes driving.
Warning!G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
may lose control of the vehicle.
Continued driving with a flat tire will cause
excessive heat build-up and possibly a fire.
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