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X
Apply the parking brake.
X Bring the front wheels into the straight-
ahead position.
X Move the selector lever to position P.
X Switch off the engine.
X Remove the SmartKey from the ignition
lock.
The steering wheel lock stays active for as
long as the SmartKey is removed.
X All occupants must get out of the vehicle.
Make
sure that they are not endangered as
they do so.
X Make sure that no one is near the danger
area while a wheel is being changed.
Anyone who is not directly assisting in the
wheel change should, for example, stand
behind the barrier.
X Get out of the vehicle. Pay attention to
traffic conditions when doing so.
X Close the driver's door. Battery (vehicle)
Important safety notes
Special tools and expert knowledge are
required when working on the battery, e.g.
removal and installing. You should therefore
have
all work involving the battery carried out
at a qualified specialist workshop. G
WARNING
Work carried out incorrectly on the battery
can, for example, lead to a short circuit and
damage
your vehicle's electronic system. This
can disrupt driving safety systems such as
ABS (anti-lock braking system) or ESP ®
(Electronic Stability Program).
R If ABS malfunctions, the wheels can lock
during braking. This limits the steerability
of the vehicle when braking and the braking distance may increase. There is a risk of
accident.
R If
ESP ®
malfunctions, the vehicle will not be
stabilised if it starts to skid or a wheel starts
to spin. There is a risk of accident.
You should therefore have all work involving
the battery carried out at a qualified specialist
workshop. 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
Electrostatic build-up can lead to the creation
of sparks, which could ignite the highly
explosive
gases of a battery. There is a risk of
an explosion.
Before handling the battery, touch the vehicle
body to remove any existing electrostatic
build-up. 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 Battery (vehicle)
305
Breakdown assistance
Z
Page 310 of 364

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, 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 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, non-combusted fuel may
damage the catalytic converter and create a risk of fire.
Do not use a rapid charging device to start the vehicle.
Make sure the jumper cables are not damaged.
Make sure the jumper cables are not touching any other metal objects when they are
connected to the battery. 308
Jump-starting
Breakdown assistance
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Position number
B identifies the charged battery of the other vehicle or an equivalent jump-
starting device.
The jump-start terminal point consists of terminals ; and ?.
X Lift up cover : of 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.
X Connect negative terminal A
of donor battery B to ground point = of your vehicle using
the jumper cable, connecting the jumper cable to donor battery B first.
X Start the engine.
X First, remove the jumper cable from ground point = and negative terminal A, then from
positive
terminal ; and positive terminal ?, each time disconnecting from the battery on
your own vehicle first.
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
G
WARNING
The vehicle is braked when the HOLD function
or DISTRONIC PLUS is activated. Therefore, deactivate HOLD and DISTRONIC PLUS if the
vehicle is to be towed.
! The vehicle can be towed a maximum of
30 miles (50km). The towing speed of
30 mph (50 km/h
) must not be exceeded.310
Towing and tow-starting
Breakdown assistance