
Display messagesPossible causes/consequences and M Solutions$
(USA only)
J
(Canada
only)Check
Brake
Fluid
LevelThere is insufficient brake fluid in the reservoir.
Risk of accident!XStop the vehicle in a safe location or as soon as it is safe
to do so.XEngage the parking brake.XDo not drive any further.XContact an authorized Mercedes-Benz Center or call
Roadside Assistance.
Do not add brake fluid! This will not solve the problem.
GWarning!
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.
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Display messagesPossible causes/consequences and M Solutions+Key Not
Detected
(message
appears in
red)The SmartKey with KEYLESS-GO is not detected while the
engine is running because the SmartKey is not in the vehicle.XStop the vehicle as soon as it is safe to do so.XEngage the parking brake.XSearch for the SmartKey.
The vehicle cannot be locked centrally nor can the engine
be started again after the engine is stopped.+Key Not
Detected
(message
appears in
red)The SmartKey with KEYLESS-GO is not detected while the
engine is running because there is strong radio-frequency
interference.XStop the vehicle as soon as it is safe to do so.XEngage the parking brake.XRemove the KEYLESS-GO button from the starter switch
( Y page 77).XOperate the vehicle with the SmartKey in the starter switch.+Key Not
Detected
(message
appears in
white)The SmartKey with KEYLESS-GO is momentarily not detected.XChange the position of the SmartKey in the vehicle.XIf necessary, remove the KEYLESS-GO button from the
starter switch ( Y page 77).+Remove
'Start'
Button
and
Insert KeyThe KEYLESS-GO system is malfunctioning.XRemove the KEYLESS-GO button from the starter switch
( Y page 77).XOperate the vehicle with the SmartKey in the starter switch.¥Check
Washer
FluidThe water level has dropped to approximately 1.1 US qts
(1.0 l).XAdd washer fluid ( Y page 217).278Vehicle status messages in the multifunction displayPractical hints
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Display messagesPossible causes/consequences and M SolutionsDPower
Steering
Malfunctio
n
See
Operator's
ManualPower assistance for the steering system is not available. A
considerably higher degree of effort is necessary to steer the
vehicle.XCheck whether you are capable to apply the higher degree
of effort necessary to safely steer the vehicle.
If you are able to steer the vehicle safely:
XContinue driving with added caution.XHave the system checked at an authorized Mercedes-Benz
Center.
If, in any way, you feel that you are not able to steer the vehicle
safely:
XStop the vehicle in a safe location as soon as it is safe to
do so.XApply the parking brake.XDo not continue to drive.XContact an authorized Mercedes-Benz Center.
Engine
Display messagesPossible causes/consequences and M Solutions+Check
Coolant
Level See
Operator's
ManualThe coolant level is too low.XAdd coolant ( Y page 216).XIf you have to add coolant frequently, have the cooling
system checked at an authorized Mercedes-Benz Center.GWarning!
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 the 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.
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Display messagesPossible causes/consequences and M Solutions?Coolant
Low Stop
Vehicle!
Turn
Engine OffThe poly-V-belt could be broken.XStop the vehicle immediately as soon as it is safe to do so.XTurn off the engine immediately.XCheck the poly-V-belt.XIf 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.XIf it is intact: Do not continue to drive the vehicle with this
message displayed. Doing so could result in serious engine
damage that is not covered by the Mercedes-Benz Limited
Warranty.XObserve the coolant temperature gauge in the instrument
cluster.XDrive to the nearest authorized Mercedes-Benz Center
immediately.?The radiator cooling fan is malfunctioning.XObserve the coolant temperature gauge in the instrument
cluster.
If the coolant temperature is below 248‡ (120†), you may
continue driving to an authorized Mercedes-Benz Center.XAvoid placing heavy loads on the engine (e.g. by driving
uphill) as well as stop-and-go traffic.XHave the fan replaced as soon as possible.#The battery is no longer charging.
Possible causes:
R alternator malfunctioning
R broken poly-V-belt
R a malfunction in the electronic systemXStop immediately in a safe location or as soon as it is safe
to do so and check the poly-V-belt.XIf 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.XIf it is intact: Drive to the nearest authorized Mercedes-
Benz Center immediately. Adjust driving to be consistent
with reduced braking responsiveness.Vehicle status messages in the multifunction display281Practical hintsX204_AKB; 3; 23, en-USd2ureepe,Version: 2.11.8.12009-07-16T19:16:58+02:00 - Seite 281Z

Display messagesPossible causes/consequences and M Solutions4Check
Engine
Oil At
Next
RefuelingThe engine oil has dropped to a critical level.XCheck the engine oil level ( Y page 215) and add engine oil
as required ( Y page 216).XIf you must add engine oil frequently, have the engine
checked for possible leaks.If the message Check Engine Oil At Next
Refueling appears while the engine is
running and at operating temperature, the
engine oil level has dropped to approximately
the minimum level.
The message will be stored in the vehicle
status message memory after you have
cleared it from the multifunction display.
Visually check for oil leaks. If there are no
obvious oil leaks, drive to the nearest service
station to refill your engine oil to the required
level.For information on approved engine oils
contact an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only).
! 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.Display messagesPossible causes/consequences and M SolutionsCThe fuel level is low.XRefuel at the next gas station.8Fuel
Level LowThe fuel level has dropped below the reserve mark.XRefuel at the next gas station.8Gas Cap
LooseA loss of pressure has been detected in the fuel system. The
fuel cap may not be closed properly or the fuel system may
be leaking.XCheck the fuel cap ( Y page 212).XIf it is not closed properly: Close the fuel cap.XIf it is closed properly: Have the fuel system checked at
an authorized Mercedes-Benz Center.282Vehicle status messages in the multifunction displayPractical hints
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BrakeProblemPossible causes/consequences and M Solutions!The yellow ABS
indicator lamp
comes on while
the engine is
running.The ABS has detected a malfunction and switched off. The BAS,
the ESP ®
, and the EBP are also switched off.
The brake system is still functioning normally but without the
systems specified above available.
If the ABS control unit is malfunctioning, other systems such as
the navigation system or the automatic transmission may also be
malfunctioning.XContinue driving with added caution. Wheels may lock during
hard braking, reducing steering capability.XAdjust driving to be consistent with reduced braking
responsiveness.XRead and observe messages that may appear in the
multifunction display ( Y page 262).XHave the system checked at an authorized Mercedes-Benz
Center as soon as possible.
Failure to follow these instructions increases the risk of an
accident.
!The yellow ABS
indicator lamp
comes on while
the engine is
running.The ABS has switched off due to insufficient power supply.
The battery might not be charged sufficiently.
When the voltage is above the required value again, the ABS is
operational again. The ABS indicator lamp should go out.XContinue driving with added caution. Wheels may lock during
hard braking, reducing steering capability.XAdjust driving to be consistent with reduced braking
responsiveness.XRead and observe messages that may appear in the
multifunction display ( Y page 262).XIf the ABS indicator lamp does not go out: Have the alternator
and the battery checked.What to do if …289Practical hintsX204_AKB; 3; 23, en-USd2ureepe,Version: 2.11.8.12009-07-16T19:16:58+02:00 - Seite 289Z

ProblemPossible causes/consequences and M Solutions!The yellow ABS
indicator lamp
comes on while
the engine is
running.The ABS is temporarily not available. The ESP ®
, the BAS, and the
EBP are also unavailable.
The self-diagnosis has not been completed yet.
The brake system is still functioning normally but without the
systems specified above.
The indicator lamp will go out after driving a short distance at a
vehicle speed of above 12 mph (20 km/h).
If the ABS indicator lamp does not go out:XContinue driving with added caution. Wheels may lock during
hard braking, reducing steering capability.XAdjust driving to be consistent with reduced braking
responsiveness.XRead and observe messages that may appear in the
multifunction display ( Y page 262).XHave the system checked at an authorized Mercedes-Benz
Center as soon as possible.
Failure to follow these instructions increases the risk of an
accident.
!
d
The yellow ABS
indicator lamp and the
yellow ESP ®
warning
lamp come on while the
engine is running and
an acoustic warning
sounds.The brake system is still functioning normally but due to a
malfunction, the ABS, the BAS, the EBP, and the ESP ®
are
unavailable.XContinue driving with added caution. Wheels may lock during
hard braking, reducing steering capability.XRead and observe messages that may appear in the
multifunction display ( Y page 262).XHave the system checked at an authorized Mercedes-Benz
Center as soon as possible.
Failure to follow these instructions increases the risk of an
accident.
290What to do if …Practical hints
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ProblemPossible causes/consequences and M Solutions!
d
The red brake warning
lamp comes on while
driving. In addition, the
yellow ABS indicator
lamp, and the yellow
ESP ®
warning lamp
come on and an
acoustic warning
sounds.The Electronic Brake Proportioning (EBP) switched off due to a
malfunction.
The ABS, the BAS, and the ESP ®
are also switched off.
The brake system is still functioning normally but without the
systems specified above available.XContinue driving with added caution. Wheels may lock during
hard braking, reducing steering capability.XAdjust driving to be consistent with reduced braking
responsiveness.XRead and observe messages that may appear in the
multifunction display ( Y page 262).XHave the system checked at an authorized Mercedes-Benz
Center as soon as possible.
Failure to follow these instructions increases the risk of an
accident.
$ (USA only)
J (Canada only)
The red brake warning
lamp comes on while
driving and an acoustic
warning sounds.You are driving with the parking brake engaged.XRelease the parking brake.$ (USA only)
J (Canada only)
The red brake warning
lamp comes on while
the engine is running.There is insufficient brake fluid in the reservoir.
Risk of accident!XDo not drive any further. Stop the vehicle in a safe location as
soon as it is safe to do so.XEngage the parking brake.XRead and observe messages that may appear in the
multifunction display ( Y page 262).XContact an authorized Mercedes-Benz Center.
Do not add brake fluid! This will not solve the problem.
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.
! 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.What to do if …291Practical hintsX204_AKB; 3; 23, en-USd2ureepe,Version: 2.11.8.12009-07-16T19:16:58+02:00 - Seite 291Z