
towing methods and the vehicle requires
towing with all four wheels on the ground.
Towing the vehicle with all four wheels on the
ground is only permissible for distances up to30 miles (50 km) and at a speed not to exceed
30 mph (50 km/h). For more information, see
“Towing the vehicle”.Display messagesPossible causes/consequences and 0050 Solutions0027
(USA only)
004D
(Canada
only)Reduced
Brake
Effect
Start
EngineThe battery has insufficient voltage and cannot supply
sufficient power to the electro-hydraulic brake system.XStart the engine.
The message disappears when sufficient voltage is
available.GWarning!
Inhalation of exhaust gas is hazardous to your
health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and lead to death. Do not
run the engine in confined areas (such as a
garage) which are not properly ventilated.Display messagesPossible causes/consequences and 0050 Solutions0026Brake WearThe brake pads have reached their wear limit.XHave the brake pads replaced as soon as possible.
!
Brake pad thickness must be visually inspected by a qualified technician at the intervals
specified in the Maintenance Booklet.
GWarning!
Have brake pad replacement and other work
on the electro-hydraulic brake system carried
out by qualified technicians only. Contact an
authorized Mercedes-Benz Center for further
information.
The electro-hydraulic brake system must be
deactivated prior to working on the system.
High pressure is intermittently built up in the
system as part of its automatic self-test.
In addition, the system is automatically
activated when the vehicle is unlocked by
remote control, when the driver or passenger
door is opened, when the SmartKey in the
starter switch is turned to position 1 or the
KEYLESS-GO start/stop button is pressed
once, when the brake pedal is depressed or
when the parking brake is released. Failure to
deactivate the system prior to maintenance
will cause brake pistons to extend and brake
fluid to leak, which may result in injuries
(contusions and acid burns). Extended brake
pistons may also cause injury.238Vehicle status messages in the multifunction displayPractical hints
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Display messagesPossible causes/consequences and 0050 Solutions003FThe battery is no longer charging.
Possible causes:
R alternator malfunctioning
R broken poly-V-belt
R a malfunction in the electronic system
Do not forget that the brake system requires electrical energy
and may be operating with restricted capability. Considerably
greater brake pedal force is required and the stopping
distance is increased.XStop 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.003FBattery/
Alternator
Stop CarThe battery is defective.
The electro-hydraulic brake system requires electrical energy
and therefore has only limited operation. Considerably
greater brake pedal force is required and the stopping
distance is increased.XStop the vehicle in a safe location or as soon as it is safe
to do so.XAdjust driving to be consistent with reduced braking
responsiveness.XContact an authorized Mercedes-Benz Center.00B4Engine
Oil Level
Check
LevelVehicles with oil dipstick only:
The engine oil has dropped to a critical level.XCheck the engine oil level ( Y page 181) and add engine oil
as required ( Y page 183).XIf you must add engine oil frequently, have the engine
checked for possible leaks.Vehicle status messages in the multifunction display247Practical hints230_AKB; 6; 22, en-USd2ureepe,Version: 2.11.8.12009-07-28T18:49:58+02:00 - Seite 247Z

BrakeProblemPossible causes/consequences and 0050 Solutions0031The 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 hill-start assist system (SL 63 AMG only) are
also switched off.
The electro-hydraulic 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 226).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 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 226).XIf the ABS indicator lamp does not go out: Have the alternator
and the battery checked.0027 (USA only)
004D (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.What to do if …255Practical hints230_AKB; 6; 22, en-USd2ureepe,Version: 2.11.8.12009-07-28T18:49:58+02:00 - Seite 255Z

locked or unlocked. It is recommended to
have the batteries replaced at an authorized
Mercedes-Benz Center.
GWarning!
Batteries contain poisonous and corrosive
substances. Therefore, keep the batteries out
of reach of children.
If a battery is swallowed, seek medical help
immediately.
GWarning!
SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. Check with
your local government’s disposal guidelines.
California residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm.
Batteries contain materials that can harm the
environment if disposed of improperly.
Recycling of batteries is the preferred method
of disposal. Many states (USA only) or
provinces (Canada only) require sellers of
batteries to accept old batteries for recycling.
When inserting the batteries, make sure they
are clean and free of lint.
When replacing batteries, always replace
both batteries.
iThe required replacement batteries are
available at any authorized Mercedes-Benz
Center.
Replacement batteries: Lithium, type
CR 2025 or equivalent.
XRemove the mechanical key from the
SmartKey (Y page 267).SmartKeyXPress mechanical key \000G into the SmartKey
opening until battery compartment
cover \000F opens. Do not keep the cover
shut.
XRemove the battery compartment cover.XPat the SmartKey against the palm of your
hand until battery \000

SmartKey with KEYLESS-GOXInsert 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

Be careful not to damage the locking tabs
or clamp the plastic retaining strap.
MOExtended system
The MOExtended system allows you to
continue driving your vehicle even if there is
a total loss of pressure in one or more tires.
You may only use the MOExtended system in
conjunction with the Advanced TPMS
( Y page 190).
The maximum distance in emergency mode
depends on the vehicle’s load. It is 50 miles
(80 km) if the vehicle is partially loaded and
18 miles (30 km) if the vehicle is fully loaded.
The point at which the maximum driving
distance in emergency mode begins is when
the warning message appears in the
multifunction display indicating that there is
a loss of tire inflation pressure.
XDo not exceed the maximum speed of
50 mph (80 km/h).GWarning!
In emergency mode, your vehicle’s driving
characteristics are diminished in such
situations as:
R driving around curves
R while braking
R while accelerating rapidly
Therefore, your driving style must be adapted
accordingly. Avoid abrupt steering and driving
maneuvers, as well as driving over obstacles
(road curbs, potholes, or off-road areas). This
is especially important if the vehicle is heavily
loaded.
The emergency driving distance that can be
achieved greatly depends on the demands
placed on the vehicle. Depending on speed,
load, driving maneuvers, road conditions,
outside temperature, etc., the distance can be
significantly shorter or, if the vehicle is driven
cautiously, somewhat longer.
Do not continue driving in emergency mode if
R you notice knocking sounds
R the vehicle starts to shake
R smoke develops and you smell rubber
R ESP ®
is intervening continuously
R you notice tears on the tire sidewalls
After driving in emergency mode, you must
have the rims inspected by an authorized
Mercedes-Benz Center to check if they are
suitable for further use. The failed tire must
be replaced in any case.
When replacing individual or all tires on the
vehicle, make sure only tires marked with
“MOExtended” are mounted in the size
specified for your vehicle ( Y page 299).
Battery
Safety notes
These batteries should always be sufficiently
charged in order to achieve their rated service
life. Refer to Maintenance Booklet for battery
maintenance intervals.
If you use your vehicle mostly for short-
distance trips, you will need to have the
battery charge checked more frequently.
When replacing a battery, always use a
battery approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, contact an
authorized Mercedes-Benz Center about
steps you need to observe.
GWarning!
Observe all safety instructions and
precautions when handling automotive
batteries.
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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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The factory-equipped battery may only be
replaced with a battery that
R has the same security features
R is of identical size
R is of identical voltage
R is of identical capacity
! As any other battery, the battery may
discharge if you do not operate the vehicle
for an extended period of time. Have the
battery disconnected at a qualified
workshop or an authorized Mercedes-Benz
Center in such a case. You may also
connect an accessory battery charge unit
expressly approved by Mercedes-Benz for
your vehicle model to maintain the battery
charge. Contact an authorized Mercedes-
Benz Center for further information.
The battery, the battery ventilation hose
and the lateral plug must always be
securely installed when the vehicle is in
operation.
! Never loosen or detach battery terminal
clamps while the engine is running or the
SmartKey is in the starter switch or
KEYLESS-GO button is in position 1.
Otherwise the alternator and other
electronic components could be severely
damaged.
Have the battery checked regularly at an
authorized Mercedes-Benz Center.
Refer to Maintenance Booklet for
maintenance intervals or contact an
authorized Mercedes-Benz Center for
further information.
i After battery power was interrupted, do
the following:
R Synchronize the ESP ®
(Y page 228).
R Synchronize the power windows
( Y page 98).Charging the batteryGWarning!
Never charge a battery while still installed in
the vehicle unless the accessory battery
charge unit approved by Mercedes-Benz is
being used. Gases may escape during
charging and could cause an explosion that
may result in personal injury, paint damage or
corrosion.
An accessory battery charge unit specially
adapted for Mercedes-Benz vehicles and
tested and approved by Mercedes-Benz is
available. It permits the charging of the
battery in its installed position. Contact an
authorized Mercedes-Benz Center for
information and availability.
Charge battery in accordance with the
separate instructions for the accessory
battery charger.
Have the battery charged at an authorized
Mercedes-Benz Center. If you charge the
battery yourself, follow the operating
instructions for your charging device.
Only use a battery charge unit with a
maximum charging voltage of 14.8 V.
XCharge battery in accordance with the
instructions of the battery charger
manufacturer.
Jump starting
GWarning!
Failure to follow these directions will cause
damage to the electronic components, and
can lead to a battery explosion and severe
injury or death.
Never lean over batteries while connecting or
jump starting. 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
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