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In order for the battery to achieve the maximum
possible service life, it should always be suffi-
ciently charged.
Like other batteries, the vehicle battery may
discharge over time if you do not use the vehicle. In such cases, have the battery disconnected at
a qualified specialist workshop. However, you
can also charge the battery with a charger rec-
ommended by Mercedes-Benz. For more infor-
mation, please contact a qualified specialist
workshop.
Have the battery charge checked more fre-
quently if you use the vehicle mainly for short
trips or if you leave it standing idle for an exten- ded period. Consult a qualified specialist work-
shop if you wish to leave your vehicle parked up
for a long period of time.
When you park the vehicle, remove the key if you do not require any electrical consumers. The
vehicle will then use very little energy, thus con- serving battery power.
If the power supply has been interrupted, e.g. if
the battery was discharged, you will have to:
R set the clock using the multimedia system;
see the separate operating instructions
R reset the function for folding the exterior mir-
rors in/out automatically, by folding the mir-
rors out once (Y page 113) Charging the battery
G
WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, naked flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery. G
WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not breathe in any battery gases. Do not
lean over the battery. Keep the batteries out of the reach of children. Immediately rinse off
battery acid thoroughly with plenty of clean
water and seek medical attention at once. G
WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery, gases can escape from the battery. There is a risk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
! Only use battery chargers with a maximum
charging voltage of 14.8 V.
! Only charge the battery using the jump-start
connection point.
The jump-starting connection point is in the
engine compartment (Y page 325).
X Open the bonnet.
X Connect the battery charger to the positive
terminal and earth point in the same order as
when connecting the donor battery in the
jump-starting procedure (Y page 325).
If the indicator/warning lamps do not light up in
the instrument cluster at low temperatures, it is very likely that the discharged battery has fro-
zen. In this case, you may neither jump-start the vehicle nor charge the battery. The service life of
a battery that has been thawed may be reduced. The starting characteristics may be impaired,
especially at low temperatures. Have the
thawed battery checked at a qualified specialistworkshop.
Only charge the installed battery with a battery
charger which has been tested and approved by Mercedes-Benz. A battery charger unit specially
adapted for Mercedes-Benz vehicles and tested and approved by Mercedes-Benz is available as
an accessory. This device permits charging of
the battery while it is installed. Contact a
Mercedes-Benz Service Centre for information
and availability. Read the battery charger's
operating instructions before charging the bat-
tery. 324
Battery (vehicle)Breakdown assistance
Page 328 of 369

Jump-starting
For the jump-starting procedure, use only the jump-starting connection point, consisting of a pos- itive terminal and an earth point, in the engine compartment. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing. Do not breathe in any battery gases. Do not lean over the battery. Keep the batteries out of the reach of children. Immediately rinse off battery acid
thoroughly with plenty of clean water and seek medical attention at once. G
WARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, naked flames, creating sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting. Do not lean over a battery. G
WARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or sparks
are created, the hydrogen gas can ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
R Never place metal objects or tools on a battery.
R It is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
R When jump-starting, make sure that the battery poles with identical polarity are connected.
R It is particularly important to observe the described order when connecting and disconnecting
the jump leads.
R Never connect or disconnect the battery terminals while the engine is running. G
WARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting the
vehicle or charging the battery, gases can escape from the battery. There is a risk of an explosion.
Allow the frozen battery to thaw out before charging it or jump-starting.
! Vehicles with a petrol engine:
avoid repeated and lengthy starting attempts. Otherwise, the
non-combusted fuel may damage the catalytic converter.
If the indicator/warning lamps do not light up in the instrument cluster at low temperatures, it is very likely that the discharged battery has frozen. In this case you may neither jump-start the vehicle norcharge the battery. Let the battery thaw first. The service life of a battery that has been thawed may
be reduced. The starting characteristics may be impaired, especially at low temperatures. Have the
thawed battery checked at a qualified specialist workshop. Jump-starting
325Breakdown assistance Z
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Do not use a rapid charging device to start the vehicle. If your vehicle's battery is discharged, the
engine can be jump-started from another vehicle or from a donor battery using jump leads. Observe the following points:
R the battery is not accessible in all vehicles. If the other vehicle's battery is not accessible, jump-
start the vehicle using a donor battery or a jump-starting device
R vehicles with a petrol engine: jump-start the vehicle only when the engine and exhaust system
are cold
R do not start the engine if the battery is frozen. Let the battery thaw first
R jump-starting may be performed only using batteries with a nominal voltage of 12 V
R only use jump leads that are not damaged and have a sufficient cross-section and insulated
terminal clamps.
R make sure that the two vehicles do not touch
Make sure that:
R the jump leads are not damaged
R non-insulated parts of the terminal clamps do not come into contact with other metal parts while
the jump leads are connected to the battery
R the jump leads cannot come into contact with parts that can move when the engine is running,
such as the V-belt pulley or the fan
X Secure the vehicle by applying the electric parking brake.
X Manual transmission: depress the clutch pedal fully and shift to neutral.
X Automatic transmission: shift the transmission to position j.
X Turn the key to position gin the ignition lock and remove it.
X Switch off all electrical consumers, e.g. rear window heating, lighting etc.
X Open the bonnet. Position number
Bidentifies the charged battery of the other vehicle or an equivalent jump-starting
device.
X Press together cover :of positive clamp ;and slide it back.
X Connect positive terminal ;on your vehicle to positive terminal =of donor battery Busing the
jump lead. beginning with your own battery.
X Start the engine of the donor vehicle and run it at idling speed. 326
Jump-startingBreakdown assistance