Battery (vehicle)
12 V battery – important safety notes Hybrid vehicles: make sure that you read the
separate Operator's Manual. You could other-
wise fail to recognize dangers, e.g. due to high
voltage.
Special tools and expert knowledge are required
when working on the battery, e.g. removal and
installation. 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 lead, for example, to a short circuit and
thus damage the vehicle electronics. This can
lead to function restrictions applying to
safety-relevant systems, e.g the lighting sys-
tem, the ABS (anti-lock braking system) or the
ESP ®
(Electronic Stability Program). The oper-
ating safety of your vehicle may be restricted.
You could lose control of the vehicle, for
example: R
when braking R
in the event of abrupt steering maneuvers
and/or when the vehicle's speed is not
adapted to the road conditions
There is a risk of an accident.
In the event of a short circuit or a similar inci-
dent, contact a qualified specialist workshop
immediately. Do not drive any further. You
should have all work involving the battery car-
ried out at a qualified specialist workshop.
For further information about ABS ( Y
page 66)
and ESP ®
( Y
page 71).
Mercedes-AMG vehicles:
G WARNING
Electrostatic build-up can lead to the creation
of sparks, which could ignite the highly explo-
sive 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. The highly flammable gas mixture forms when
charging the battery as well as when jump-start-
ing.
Always make sure that neither you nor the bat-
tery is electrostatically charged. A build-up of
electrostatic charge can be caused, for exam-
ple: 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 car-
pet or other synthetic materials R
if you wipe the battery with a cloth
G WARNING
During the charging process, a battery produ-
ces 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 con-
tact with vehicle parts. R
Never place metal objects or tools on a bat-
tery. R
It is important that you observe the descri-
bed 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 dis-
connecting 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 skin, eyes or clothing. Do
not inhale any battery gases. Do not lean over
the battery. Keep children away from batter-
ies. Wash away battery acid immediately with
plenty of clean water and seek medical atten-
tion.
All vehicles:332
Battery (vehicle)
Breakdo wn assis tance
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.
If, at low temperatures, the indicator lamps/warning lamps in the instrument cluster do not light up,
it is highly likely that the discharged battery has frozen. In this case, you may neither charge the
battery nor jump-start the vehicle. The service life of a thawed-out battery may be shorter. The
starting characteristics can be impaired, particularly at low temperatures. Have the thawed-out
battery checked at a qualified specialist workshop.
All vehicles:
! 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. R
All vehicles except Mercedes-AMG vehicles: 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 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 which can move when the engine is
ru nning, such as the V-belt pulley or the fan. X
Secure the vehicle by applying the electric parking brake. X
Shift the transmission to position P .X
Make sure that the ignition is switched off. All indicator lamps in the instrument cluster must be
off. When using the SmartKey, turn the SmartKey to position 0 in the ignition lock and remove it
( Y
page 145).X
Switch off all electrical consumers, e.g. rear window defroster, lighting, etc. X
Open the hood.336
Jump-starting
Breakdown assistance
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 Hybrid vehicles: make sure that you read the
separate operating instructions. You could oth-
erwise fail to recognize dangers, e.g. due to high
voltage.
G WARNING
Functions relevant to safety are restricted or
no longer available if: R
the engine is not running. R
the brake system or the power steering is
malfunctioning. R
there is a malfunction in the voltage supply
or the vehicle's electrical system.
If your vehicle is being towed, much more
force may be necessary to steer or brake.
There is a risk of an accident.
In such cases, use a tow bar. Before towing,
make sure that the steering moves freely.
G WARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissible
gross weight of your vehicle, the: R
the towing eye could detach itself R
the vehicle/trailer combination could roll-
over.
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the per-
missible gross weight of your vehicle.
Details on the permissible gross vehicle weight
of your vehicle can be found on the vehicle iden-
tification plate ( Y
page 370).
! When Active Brake Assist, Distance Pilot
DISTRONIC or the HOLD function is activated,
the vehicle brakes automatically in certain
situations. To avoid damage to the vehicle, deactivate
these systems in the following or similar sit-
uations: R
when towing the vehicle R
in the car wash
! Make sure that the electric parking brake is
released. If the electric parking brake is faulty,
visit a qualified specialist workshop.
! Secure the tow rope or tow bar to the towing
eye only. Otherwise, the vehicle could
become damaged.
! Do not use the towing eyes for recovery pur-
poses as this could damage the vehicle. If in
doubt, recover the vehicle with a crane.
! When towing, pull away slowly and
smoothly. If the tractive power is too high, the
vehicles could be damaged.
! Shift the automatic transmission to N an d
do not open the driver's or front passenger's
door during towing. The automatic transmis-
sion may otherwise shift to position P , which
could damage the transmission.
! Do not tow with sling-type equipment. This
could damage the vehicle.
! The vehicle can be towed a maximum of
30 miles (50km). The towing speed of 30 mph
(50 km/ h) must not be exceeded.
If the vehicle has to be towed more than
30 miles (50km), the entire vehicle must be
raised and transported.
It is better to have the vehicle transported than
to have it towed away.
If the vehicle has suffered transmission damage,
have it transported on a transporter or trailer.
The automatic transmission must be in position
N when the vehicle is being towed.
If the automatic transmission cannot be shifted
to position N , have the vehicle transported on a
transporter or trailer.338
Towing and tow-starting
Breakdown assistance
the combination switch, the hazard warning
lamp starts flashing again.
Transporting the vehicle
General notes
! When the vehicle is loaded for transport, the
front and rear axles must be stationary and on
the same transportation vehicle. Positioning
over the connection point of the transport
vehicle is not permitted. The drive train may
otherwise be damaged.
! You may only secure the vehicle by the
wheels, not by parts of the vehicle such as
axle or steering components. Otherwise, the
vehicle could be damaged.
The towing eye can be used to pull the vehicle
onto a trailer or transporter for transporting pur-
poses. X
Turn the SmartKey to position 2 in the ignition
lock. X
Shift the automatic transmission to position
N .
As soon as the vehicle has been loaded: X
Prevent the vehicle from rolling away by
applying the electric parking brake. X
Shift the automatic transmission to posi-
tion P .X
Turn the SmartKey to position 0 in the ignition
lock and remove it. X
Secure the vehicle. Notes on 4MATIC vehicles
! Vehicles with 4MATIC must not be towed
with either the front or the rear axle raised, as
doing so will damage the transmission.
Vehicles with 4MATIC may either be towed away
with both axles on the ground or be loaded up
and transported.
If the vehicle's transmission, front, or rear axle is
damaged, have the vehicle transported on a
truck or trailer.
In the event of damage to the electrical sys-
tem: if the battery is defective, the automatic
transmission will be locked in position P . To shift
the automatic transmission to position N , you
must provide power to the vehicle's electrical
system in the same way as when jump-starting
( Y
page 335).
Have the vehicle transported on a transporter or
trailer.
Tow-starting (emergency engine
starting)
! Vehicles with automatic transmission must
not be tow-started. You could otherwise dam-
age the automatic transmission.
i Information on "Jump-starting"
( Y
page 335).
Fuses
Important safety notes
G WARNING
If you manipulate or bridge a faulty fuse or if
you replace it with a fuse with a higher amper-
age, the electric cables could be overloaded.
This could result in a fire. There is a risk of an
accident and injury.
Always replace faulty fuses with the specified
new fuses having the correct amperage.
Blown fuses must be replaced with fuses of the
same rating, which you can recognize by the
color and value. The fuse ratings are listed in the
fuse allocation chart. The fuse allocation chart is
in the vehicle document wallet.340
Fuses
Breakdown assistance