On board computer MERCEDES-BENZ C-Class 2011 W204 Repair Manual

Display messagesPossible causes/consequences and M Solutions+
Key Detected in
VehicleThe KEYLESS-GO key has been detected inside the vehicle during
locking.XRemove the KEYLESS-GO key from the vehicle.+
Remove 'Start'
Button and Insert
KeyKEYLESS-GO is temporarily malfunctioning or is defective. A
warning tone also sounds.XInsert the SmartKey into the ignition lock and turn it to the
desired position.XVisit a qualified specialist workshop.+
Close Doors to
Lock VehicleAt least one door is open. A warning tone also sounds.XClose all doors and lock the vehicle again.
Warning and indicator lamps in the instrument cluster
Brakes
ProblemPossible causes/consequences and M Solutions$ (USA only)
J (Canada only)
The red brake system
warning lamp comes on
while the vehicle is
moving. A warning tone
also sounds.You are driving with the parking brake engaged.XRelease the parking brake.
The warning lamp goes out and the warning tone ceases.$ (USA only)
J (Canada only)
The red brake system
warning lamp comes on
while the engine is
running. A warning tone
also sounds.GRisk of accident
There is insufficient brake fluid in the fluid reservoir.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.XEngage the parking brake.XConsult a qualified specialist workshop immediately.XObserve the additional display messages in the multifunction
display.
Do not add brake fluid. This will not rectify the problem.
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GWarning
Driving with the brake warning lamp illuminated 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.
Seat belts
ProblemPossible causes/consequences and M Solutions7
After starting the
engine, the red seat
belt warning lamp lights
up for 6 seconds.The seat belt warning lamp reminds the driver and front passenger
to fasten their seat belts.XFasten your seat belt ( Y page 50).7
After starting the
engine, the red seat
belt warning lamp lights
up. In addition, a
warning tone sounds
for up to 6 seconds.GRisk of injury
The driver's seat belt is not fastened.
XFasten your seat belt ( Y page 50).
The warning tone ceases.7
The red seat belt
warning lamp lights up
after the engine starts,
as soon as the driver's
or the front-passenger
door is closed.GRisk of injury
The driver or front passenger has not fastened their seat belt.
XFasten your seat belt ( Y page 50).
The warning lamp goes out.GRisk of injury
There are objects on the front-passenger seat.
XRemove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out.204Warning and indicator lamps in the instrument clusterOn-board computer and displays
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ProblemPossible causes/consequences and M Solutions7
The red seat belt
warning lamp flashes
and an intermittent
audible warning
sounds.GRisk of injury
The driver or front passenger has not fastened their seat belt. In
addition, you are driving faster than 15 mph (25 km/h) or you have
briefly driven faster than 15 mph (25 km/h).
XFasten your seat belt ( Y page 50).
The warning lamp goes out and the intermittent audible warning
ceases.GRisk of injury
There are objects on the front-passenger seat. In addition, you are
driving faster than 15 mph (25 km/h) or you have briefly driven
faster than 15 mph (25 km/h).
XRemove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out and the intermittent audible warning
ceases.Warning and indicator lamps in the instrument cluster205On-board computer and displaysBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 205Z

Safety systemsProblemPossible causes/consequences and M Solutions!
The yellow ABS warning
lamp is lit while the
engine is running. GRisk of accident
ABS (Anti-lock Brake System) is deactivated due to a malfunction.
Therefore, ESP ®
(Electronic Stability Program), BAS (Brake Assist),
EBD (Electronic Brake force Distribution) and hill start assist are
also deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.
If the ABS control unit is faulty, there is also a possibility that other
systems, such as the navigation system or the automatic
transmission, will not be available.
!
The yellow ABS warning
lamp is lit while the
engine is running.GRisk of accident
ABS is temporarily unavailable. ESP ®
, BAS and EBD, for example,
are therefore not available either.
Self diagnosis is not yet complete.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XCarefully drive a suitable distance making slight steering
movements at a speed above 12 mph (20 km/h).
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.206Warning and indicator lamps in the instrument clusterOn-board computer and displays
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ProblemPossible causes/consequences and M Solutionsäå!
The yellow ESP ®
and
ESP ®
OFF warning
lamps and the yellow
ABS warning lamp are
lit while the engine is
running. A warning tone
also sounds.GRisk of accident
EBD is faulty. Therefore, ABS, BAS and hill start assist are not
available either, due to a malfunction.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.äå!
The yellow ESP ®
and
ESP ®
OFF warning
lamps and the yellow
ABS warning lamp are
lit while the engine is
running.GRisk of accident
ABS and ESP ®
are faulty. Therefore, BAS and hill start assist are
not available either, due to a malfunction.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.ä
The yellow ESP ®
warning lamp flashes
while the vehicle is in
motion.GRisk of accident
ESP ®
or traction control has intervened because there is a risk of
skidding or at least one wheel has started to spin.
Cruise control is deactivated.
XOnly depress the accelerator pedal as far as necessary when
pulling away.XRelease the accelerator pedal while the vehicle is in motion.XAdapt your driving style to suit the road and weather conditions.XDo not deactivate ESP ®
.
Exceptions: ( Y page 63).Warning and indicator lamps in the instrument cluster207On-board computer and displaysBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 207Z

ProblemPossible causes/consequences and M Solutionsä
The yellow ESP ®
warning lamp flashes
while the vehicle is in
motion.At least one wheel is spinning and ETS (Electronic Traction
System) is deactivated to prevent the brakes on the drive wheels
from overheating.XObserve the additional display messages in the multifunction
display.
ETS switches back on again as soon as the brakes have cooled
down.
The display message disappears and the ä warning lamp goes
out.
å
The yellow ESP ®
OFF
warning lamp is lit while
the engine is running. GRisk of accident
ESP ®
is deactivated. ESP ®
will not stabilize the vehicle if it starts
to skid or if a wheel starts to spin.
XReactivate ESP ®
.
Exceptions: ( Y page 63).XAdapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
XHave ESP ®
checked at a qualified specialist workshop.M (C 63 AMG only)
The yellow SPORT
handling mode warning
lamp is lit while the
engine is running. GRisk of accident
SPORT handling mode is activated. ESP ®
only stabilizes the vehicle
in extreme situations. ESP ®
intervention may not be able to
provide sufficient assistance in such situations, and the vehicle
may start to skid.
XReactivate ESP ®
.
Exceptions: ( Y page 63).
If ESP ®
cannot be activated:
XHave ESP ®
checked at a qualified specialist workshop.208Warning and indicator lamps in the instrument clusterOn-board computer and displays
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ProblemPossible causes/consequences and M Solutionsäå
The yellow ESP ®
and
ESP ®
OFF warning
lamps are lit while the
engine is running.GRisk of accident
ESP ®
, BAS and hill start assist are unavailable, due to a
malfunction. ESP ®
will not stabilize the vehicle if it starts to skid
or if a wheel starts to spin.
The brake system continues to function normally, but without the
functions listed above.
XObserve the additional display messages in the multifunction
display.XDrive on carefully.XVisit a qualified specialist workshop.6
The red SRS warning
lamp is lit while the
engine is running. GRisk of injury
The restraint systems are malfunctioning. The air bags or ETDs
may either be triggered unintentionally or, in the event of an
accident, not be triggered at all.
XDrive on carefully.XVisit a qualified specialist workshop immediately.GWarning
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 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 injury.
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EngineProblemPossible causes/consequences and M Solutions;
The yellow Check
Engine warning lamp
lights up while the
engine is running.There may be a malfunction, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system
R the fuel system
The emission limit values may have been exceeded and the engine
may be breaking in emergency mode.XHave the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states, you are required by law to visit a qualified
specialist workshop as soon as the Check Engine warning lamp
lights up. If necessary, check whether this is the case in the
state you are in.
8
The yellow reserve fuel
warning lamp flashes
while the engine is
running.The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.XCheck that the fuel filler cap is correctly closed.XIf the fuel filler cap is not correctly closed: close the fuel filler
cap.XIf the fuel filler cap is closed: visit a qualified specialist
workshop.8
The yellow reserve fuel
warning lamp lights up
while the engine is
running. The amount of fuel in the tank has dropped into the reserve range.XRefuel at the nearest gas station.?
The red coolant
warning lamp lights up
while the engine is
running and the coolant
temperature gauge is
at the start of the scale.The temperature sensor for the coolant temperature gauge is
faulty.
The coolant temperature is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions. Do not continue
driving under any circumstances.XEngage the parking brake.XConsult a qualified specialist workshop.210Warning and indicator lamps in the instrument clusterOn-board computer and displays
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ProblemPossible causes/consequences and M Solutions?
The red coolant
warning lamp comes on
while the engine is
running.The coolant level is too low.
If the coolant level is correct, the airflow to the radiator may be
blocked or the electric radiator fan may be malfunctioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XAllow the engine and coolant to cool.XCheck the coolant level and add the coolant ( Y page 240).
Observe the warning notes.XIf the coolant needs adding more often than usual, have the
engine coolant system checked.XMake sure that the air supply to the radiator is not blocked, e.g.
by snow, slush or ice.XAt coolant temperatures below 248 ‡ (120 †), continue driving
to the next qualified specialist workshop.XAvoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-start driving.?
The red coolant
warning lamp comes on
while the engine is
running. A warning tone
also sounds.The coolant has exceeded a temperature of 248 ‡ (120 †). The
airflow to the radiator may be blocked or the coolant level may be
too low.
The engine is not being cooled sufficiently and may be damaged.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XAllow the engine and coolant to cool.GWarning
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 opening the
engine hood. Stay away from the engine if you see or hear steam coming from it.
Stop the vehicle in a safe location away from other traffic. Turn off the engine, get out of the
vehicle and do not stand near the vehicle until the engine has cooled down.
! If the coolant temperature exceeds 248 ‡(120 †) do not continue driving. The engine will
otherwise be damaged.
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TiresProblemPossible causes/consequences and M Solutionsh
USA only:
The yellow combination
low tire pressure
warning lamp/TPMS
malfunction warning
lamp is lit.GRisk of accident
The tire pressure monitor has detected a loss of pressure in at
least one of the tires.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XObserve the additional display messages in the multifunction
display.XCheck the tire pressure. If necessary, correct the tire pressure
( Y page 277).XIf necessary, change a wheel ( Y page 286).h
USA only:
The yellow combination
low tire pressure
warning lamp/TPMS
malfunction warning
lamp flashes for sixty
seconds and then
remains lit.The tire pressure monitor is faulty.XObserve the additional display messages in the multifunction
display.XVisit a qualified specialist workshop.GWarning
Each tire, including the spare (if provided), should be checked every other week when cold and
inflated to the inflation pressure recommended by the vehicle manufacturer on the Tire and
Loading Information placard on the driver's door B-pillar or, if available, the tire inflation pressure
label on the inside of the fuel filler flap. If your vehicle has tires of a different size than the size
indicated on the Tire and Loading Information placard or, if available, the tire inflation pressure
label, you should determine the proper tire inflation pressure for those tires.
As an added safety feature, your vehicle has been equipped with a tire pressure monitoring
system (TPMS) that illuminates a low tire pressure warning lamp when one or more of your tires
are significantly underinflated. Accordingly, when the low tire pressure warning lamp illuminates,
you should stop and check your tires as soon as possible, and inflate them to the proper pressure.
Driving on a significantly underinflated tire causes the tire to overheat and can lead to tire failure.
Underinflation also reduces fuel efficiency and tire tread life, and may affect the vehicle's handling
and stopping ability. Please note that the TPMS is not a substitute for proper tire maintenance,
and it is the driver's responsibility to maintain correct tire pressure, even if underinflation has
not reached the level to trigger illumination of the TPMS low tire pressure warning lamp.
Your vehicle has also been equipped with a TPMS malfunction indicator to indicate when the
system is not operating properly. The TPMS malfunction indicator is combined with the low tire
pressure warning lamp. When the system detects a malfunction, the warning lamp will flash for
approximately one minute and then remain continuously illuminated. This sequence will continue
212Warning and indicator lamps in the instrument clusterOn-board computer and displays
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