
Display messagesPossible causes/consequences and 0050 Solutions0027
(USA only)
004D
(Canada
only)ABS and
ESC
Currently
Unavailabl
e See
Oper.
ManualIn addition, the yellow ESC warning lamp 00F2, the yellow
ESC OFF warning lamp 00C7, and the yellow ABS indicator
lamp 0031 come on.
The brake system still functions normally but due to
insufficient power supply, the ABS, the BAS, the BAS PLUS,
the ESC, the hill-start assist system, the HOLD function, the
Adaptive Brake Lights, the PRE-SAFE ®
system, and the
PRE-SAFE ®
Brake are unavailable.
The ATTENTION ASSIST is disabled.XContinue driving with added caution. Wheels may lock
during hard braking, reducing steering capability.XAdjust driving to be consistent with reduced braking
responsiveness.
When the voltage is above the required value again, the ABS,
the BAS, the BAS PLUS, the ESC, the hill-start assist system,
the HOLD function, the Adaptive Brake Lights, the
PRE-SAFE ®
system, and the PRE-SAFE ®
Brake are operational
again and the message should disappear.
If the message does not disappear:
XHave the alternator and the battery checked.
Failure to follow these instructions increases the risk of an
accident.
0027
(USA only)
004D
(Canada
only)EBR, ABS,
and ESC
Inoperativ
e See
Oper.
ManualIn addition, the yellow ESC warning lamp 00F2, the yellow
ESC OFF warning lamp 00C7, and the yellow ABS indicator
lamp 0031 come on and an acoustic warning sounds.
The brake system is still functioning normally but due to a
malfunction, the ABS, the BAS, the BAS PLUS, the EBP, the
ESC, the HOLD function, the Adaptive Brake Lights, the PRE-
SAFE ®
system, and the PRE-SAFE ®
Brake are unavailable.
The ATTENTION ASSIST is disabled.XContinue driving with added caution. Wheels may lock
during hard braking, reducing steering capability.XAdjust driving to be consistent with reduced braking
responsiveness.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.
468Vehicle status messages in the multifunction displayPractical hints
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Display messagesPossible causes/consequences and 0050 Solutions0049
(USA only)
0024
(Canada
only)Parking
Brake See
Oper.
ManualIn addition, the red indicator lamp for the electronic parking
brake flashes and the yellow warning lamp for the electronic
parking brake comes on.
The electronic parking brake is malfunctioning.XSwitch ignition off and back on again, and engage or release
electronic parking brake.
or
XDrive off carefully.XContact an authorized Mercedes-Benz Center as soon as
possible.0049
(USA only)
0024
(Canada
only)Parking
Brake See
Oper.
ManualWhen you engage or release the electronic parking brake, the
red indicator lamp for the electronic parking brake flashes for
approximately 10 seconds. Afterward, it goes out or comes
on continuously. The yellow warning lamp for the electronic
parking brake comes on.
The electronic parking brake is malfunctioning or overheated
for example due to overvoltage or undervoltage.XDrive off carefully.XContact an authorized Mercedes-Benz Center as soon as
possible.
In the event of overvoltage or undervoltage:
XRemove the cause of the overvoltage or undervoltage, e.g.
charge the battery or restart the engine.XSwitch ignition off and back on again, and engage or release
electronic parking brake.
If the electronic parking brake still cannot be released:
XContact an authorized Mercedes-Benz Center as soon as
possible.
If overheated:
XLet vehicle cool down, and do not engage electronic parking
brake during this time.
or
XSwitch ignition off and back on again, and engage or release
electronic parking brake.Vehicle status messages in the multifunction display471Practical hints221_AKB; 6; 20, en-USd2ugruen,Version: 2.11.8.12009-09-24T13:28:17+02:00 - Seite 471Z

Display messagesPossible causes/consequences and 0050 Solutions00B1Key Does
Not
Belong to
VehicleThe SmartKey in the starter switch does not belong to the
vehicle.XRemove the SmartKey from the starter switch.00B1Replace
Key
BatteryThe batteries in the SmartKey with KEYLESS-GO are
discharged.XReplace the batteries ( Y page 502).00B1Key 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 electronic parking brake.XSearch for the SmartKey.
The vehicle cannot be locked centrally nor can the engine
be started again after the engine is stopped.00B1Key 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 electronic parking brake.XRemove the KEYLESS-GO button from the starter switch
( Y page 285).XOperate the vehicle with the SmartKey in the starter switch.00B1Key Not
Detected
(message
appears in
red)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 285).XOperate the vehicle with the SmartKey in the starter switch.00B1Key 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 285).XOperate the vehicle with the SmartKey in the starter switch.00B1Key Being
Initialize
d… Please
WaitThe SmartKey with KEYLESS-GO is being initialized in the
vehicle.XWait until the message disappears from the multifunction
display.Vehicle status messages in the multifunction display479Practical hints221_AKB; 6; 20, en-USd2ugruen,Version: 2.11.8.12009-09-24T13:28:17+02:00 - Seite 479Z

Display messagesPossible causes/consequences and 0050 Solutions00AECoolant
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.00AEThe 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.003FThe 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.482Vehicle status messages in the multifunction displayPractical hints
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BrakeProblemPossible causes/consequences and 0050 Solutions0031The yellow ABS
indicator lamp
comes on while
the engine is
running.The brake system is still functioning normally but due to a
malfunction, the ABS, the BAS, the BAS PLUS, the ESC, the
hill-start assist system, the HOLD function, the Adaptive Brake
Lights, the PRE-SAFE ®
system, and the PRE-SAFE ®
Brake are
unavailable.
The ATTENTION ASSIST is disabled.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 452).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.
0031The yellow ABS
indicator lamp
comes on while
the engine is
running.The brake system still functions normally but due to insufficient
power supply, the ABS, the BAS, the BAS PLUS, the ESC, the
hill-start assist system, the HOLD function, the Adaptive Brake
Lights, the PRE-SAFE ®
system, and the PRE-SAFE ®
Brake are
unavailable.
The ATTENTION ASSIST is disabled.
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 452).XIf the ABS indicator lamp does not go out: Have the alternator
and the battery checked.490What to do if …Practical hints
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Unlocking the driver’s doorXInsert mechanical key \000G into the driver’s
door lock.
XTurn mechanical key \000G counterclockwise
to position \000J.
XPull the door handle past the resistance
point until the locking knob moves up.
The driver’s door is unlocked.
XPull the door handle once more to open the
driver’s door.
XTurn mechanical key \000G back and remove
it from the driver’s door lock.
Unlocking the trunk
A minimum height clearance of 5.9 ft (1.8 m)
is required to open the trunk lid.
XInsert mechanical key \000G into the trunk lid
lock.
XTurn mechanical key \000G counterclockwise
to position \000J.
! When you open the trunk, the trunk lid
swings open upwards. Always make sure
there is sufficient overhead clearance.
XTurn mechanical key \000G back and remove
it from the trunk lid lock.
Locking the vehicle
If you cannot lock the vehicle with the
SmartKey or with KEYLESS-GO, lock it as
follows:
XOpen the driver’s door and the rear left
door.
XClose the front passenger door, the right
rear door, and the trunk.
iIf you cannot close the trunk with the
remote trunk opening/closing switch,
lower the trunk lid manually and close it
with hands placed flat on the trunk lid until
it is engaged in its lock.
XPress the central locking switch
(Y page 279).
The locking knobs of the front passenger
door and the rear doors move down.
XIf the vehicle battery is disconnected or
drained: Press down the locking knobs on
the front passenger door and the rear
doors.
XExit the vehicle.XCheck whether the trunk is locked.XIf it is not locked, lock it with the
mechanical key (Y page 283).
Except for the driver’s door, the vehicle
should now be locked.
XClose the driver’s door.XEnter the vehicle through the rear left door.XPress down the locking knob of the driver’s
door.
! To prevent inadvertent lockout, make
sure to have the SmartKey with you before
proceeding with the next step. The next
step will lock the vehicle.
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XInsert the new battery with the positive
terminal (+) facing up. Use a lint-free cloth.
XInsert the tabs of the battery compartment
cover into the housing and press the cover
closed.
XSlide mechanical key \000F back into the
SmartKey.
XCheck the operation of the SmartKey.
Replacing batteries (SmartKey with
KEYLESS-GO)
XInsert mechanical key \000F into opening.XPress mechanical key \000F in direction of
arrow.
Battery compartment \000G is unlatched.
XPull battery compartment \000G out of the
SmartKey housing.
XPull out batteries \000

Risk of explosion.Fire, open flames and
smoking are prohibited
when handling batteries.
Avoid creating sparks.
Battery acid is caustic. Do
not allow it to come into
contact with skin, eyes or
clothing.
Wear suitable protective
clothing, especially gloves,
apron and faceguard.
Wear eye protection.
Rinse any acid spills
immediately with clear
water. Contact a physician
if necessary.
Keep children away.Follow the instructions in
this Operator’s Manual.
A battery contains materials that can harm
the environment if disposed of improperly. A
large 12 V storage battery contains lead.
Recycling of the battery is the preferred
method of disposal. Many states (USA only)
or provinces (Canada only) require sellers of
batteries to accept the old battery for
recycling.
GWarning!
Failure to follow these instructions can result
in severe injury or death.
Never lean over batteries while connecting.
You might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking etc.
GWarning!
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof batteries only to avoid the risk
of acid burns in the event of an accident.
Take care that you do not become statically
charged, e.g. by wearing synthetic clothing or
rubbing against textiles. For this reason, you
also should not pull or push the battery over
carpets or other synthetic materials.
Never touch the battery first. First touch the
outside body of the vehicle in order to release
any possible electrostatic charges.
Do not rub the battery with rags or cloths. The
battery could explode if touched due to
electrostatic charge or due to spark
formation.
! The battery is a Valve-Regulated Lead
Acid (VRLA) battery, also referred to as
“fleece” battery.
Such batteries do not require topping-up of
the electrolyte level. VRLA batteries
therefore do not have cell caps and the
battery cover is non-removable. Do not
attempt to open the battery as otherwise
the battery will be damaged.
VRLA batteries do not require topping-up of
the electrolyte level. They cannot be
opened to check the electrolyte level.
However, the battery condition must be
checked periodically by performing a
battery conductance test. Refer to
Maintenance Booklet for battery condition
testing intervals.
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