The highly flammable gas mixture forms when
charging the battery as well as when jump-
starting.
Always make sure that neither you nor the
battery is electrostatically charged. A build-
up of electrostatic charge can be caused, for
example:
R by wearing clothing made from synthetic
fibers
R due to friction between clothing and seats
R if you push or pull the battery across the
carpet or other synthetic materials
R if you wipe the battery with a cloth. 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 jumper cables.
R Never connect or disconnect the battery
terminals while the engine is running. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing.
Do not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash battery acid immediately with
water and seek medical attention. H
Environmental note Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately
and recycled to protect the
environment.
Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified
specialist workshop or a
special collection point for
used batteries.
! Have the battery checked regularly at a
qualified specialist workshop.
Observe the service intervals in the
Maintenance Booklet or contact a qualified
specialist workshop for more information.
! You should have all work involving the
battery carried out at a qualified specialist
workshop. In the exceptional case that it is
necessary for you to disconnect the battery
yourself, make sure that:
R you switch off the engine and remove the
SmartKey. On vehicles with KEYLESS-
GO, ensure that the ignition is switched
off. Check that all the indicator lamps in
the instrument cluster are off. Otherwise,
electronic components, such as the
alternator, may be damaged.
R you first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic
system may be damaged.
R the transmission is locked in position P
after disconnecting the battery. The
vehicle is secured against rolling away.
You can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be installed securely
during operation. Battery
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Jump-starting
G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing. Do not inhale any battery gases. Do not lean over
the battery. Keep children away from batteries. Wash battery acid immediately with water and
seek medical attention. G
WARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a risk
of an explosion.
Particularly avoid fire, open 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 jumper cables.
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. G
WARNING
Non-combusted fuel can collect in the exhaust system and ignite. There is a risk of fire. Avoid
repeated and lengthy starting attempts.
! Avoid repeated and lengthy starting attempts. Otherwise, the catalytic converter could be
damaged by the non-combusted fuel.
Do not start the vehicle using a rapid charging device. If your vehicle's battery is discharged,
the engine can be jump-started from another vehicle or from a second battery using jumper
cables. 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 second battery or a jump-starting device.
R You may only jump-start the vehicle when the engine and exhaust system are cold. 240
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R
Do not start the engine if the battery is frozen. Let the battery thaw first.
R Only jump-start from batteries with a 12 V voltage rating.
R Only use jumper cables which have a sufficient cross-section and insulated terminal clamps.
R If the battery is fully discharged, leave the battery that is being used to jump-start connected
for a few minutes before attempting to start. This charges the battery slightly.
R Make sure that the two vehicles do not touch.
Make sure that:
R the jumper cables are not damaged.
R when the jumper cables are connected to the battery, uninsulated sections of the terminal
clamp do not come into contact with other metal sections.
R the jumper cables cannot come into contact with parts such as the V-belt pulley or the fan.
These parts move when the engine is started and while it is running.
X Press the electric parking brake handle.
X Shift the transmission to Pwith the button in the center console.
X Remove the SmartKey from the ignition lock.
X Switch off all electrical consumers (e.g. radio, blower, etc.).
X Open the hood (Y page 214). Position number
Bidentifies the charged battery of the other vehicle or an equivalent jump-
starting device.
X Slide cover Aof positive terminal :in the direction of the arrow.
X Connect positive terminal :on your vehicle to positive terminal ;of donor battery B
using the jumper cable, beginning with your own battery.
X Start the engine of the donor vehicle and run it at idling speed. Jump-starting
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X
Connect negative terminal =of donor battery Bto earth point ?of your vehicle using
the jumper cable, connecting the jumper cable to donor battery Bfirst.
X Start the engine.
X Before disconnecting the jumper cables, let the engine run for several minutes.
X First, remove the jumper cables from earth point ?and negative terminal =, then from
positive clamp :and positive terminal ;. Each time beginning with your vehicle's battery.
X Slide cover Aof the positive terminal in the opposite direction to the arrow.
X Have the battery checked at a qualified specialist workshop.
i Jump-starting is not considered to be a normal operating condition.
i Jumper cables and further information regarding jump-starting can be obtained at any
qualified specialist workshop. Towing and tow-starting
Important safety notes
If the vehicle can no longer be driven because
of an accident or breakdown, you have the
following options:
R transporting the vehicle
As a rule, you should have the vehicle
transported.
R towing the vehicle with the rear axle raised
Only tow the vehicle with the rear axle
raised in exceptional cases.
R towing the vehicle with a tow rope or tow
bar
Only tow the vehicle in exceptional cases.
The engine must be running if you tow the
vehicle with a tow rope or tow bar. Observe
the following notes. G
WARNING
The rear axle locks when:
R the engine is not running
R the engine stalls while the vehicle is being
towed
R there is a malfunction in the power supply
or the vehicle's electrical system
There is a risk of an accident.
In the event of a breakdown, you should
always have the vehicle transported. G
WARNING
If the brake system or power steering is
malfunctioning and your vehicle is then towed
away, significantly more effort may be
required to steer and brake than is normally
required. There is a risk of an accident.
In such cases, use a tow bar. Before towing,
make sure that the steering moves freely.
! Use the SmartKey instead of the Start/
Stop button when towing the vehicle.
Start the engine and keep it running. Turn
the SmartKey to position 2in the ignition.
Set the transmission to Nusing the E-
SELECT lever. Make sure that you then
leave the SmartKey in position 2.
Check the transmission position in the
instrument cluster.
! Make sure that the electric parking brake
is released. If the electric parking brake is
faulty, visit a qualified specialist workshop.
Mercedes-Benz recommends that you use
an authorized Mercedes-Benz Center for
this purpose.
! When towing, pull away slowly and
smoothly. If the tractive power is too high,
the vehicles could be damaged.
! Only secure the tow rope or tow bar at the
towing eyes. Otherwise, the vehicle could
be damaged. 242
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