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 at low temperatures, it is very likely that the dis-
charged battery has frozen. 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 charac-
teristics may be impaired, especially at low temperatures. Have the thawed battery checked at a
qualified specialist workshop. 354
Jump-startingBreakdown assistance
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 second 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 second 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 Use only jump leads that 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 empty battery a little.
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 Shift the transmission to position P.
X Make sure that the ignition is switched off . All indicator lamps on the instrument cluster must be
off. When using the key, turn the key to position 0in the ignition lock and remove it (Y page 148).
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 Slide cover :of positive terminal ;in the direction of the arrow.
X Connect positive terminal ;on your vehicle to positive terminal =of donor battery Busing the
jump lead, always beginning with positive terminal ;on your own vehicle first.
X Start the engine of the donor vehicle and run it at idling speed. Jump-starting
355Breakdown assistance Z
X
Connect negative terminal ?of donor battery Bto earth point Aof your vehicle using the jump
lead, connecting the jump lead to donor battery Bfirst.
X Start the engine.
X Before disconnecting the jump leads, let the engines run for several minutes.
X First, remove the jump leads from earth point Aand negative terminal ?, then from positive
clamp ;and positive terminal =. Each time, begin at the contacts on your own vehicle first.
X After removing the jump leads, close cover :of positive terminal clamp ;.
X Have the battery checked at a qualified specialist workshop.
Jump-starting is not considered to be a normal operating condition.
i Jump-starting cables and further information regarding jump-starting can be obtained at any
qualified specialist workshop. Towing away and tow-starting
Important safety notes
G
WARNING
Safety-relevant functions are restricted or not
available if:
R the engine is not running.
R the brake system or the power steering is
malfunctioning
R the voltage supply or the vehicle's electrical
system is malfunctioning.
If your vehicle is towed, significantly greater
force may be required to steer the vehicle or
to brake. There is a risk of an accident.
In such circumstances, use a towing bar.
Make sure that the steering is moving freely
before towing. G
WARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissible gross weight of your vehicle, the:
R towing eye may be torn off
R car/trailer combination may swerve or
even overturn
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 380).
! 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 away
R in a car wash
! Make sure that the electric parking brake is
released. If the electric parking brake is faulty, visit a qualified specialist workshop.
! Only secure the tow cable or tow bar to the
towing eyes or, if available, to the trailer tow
hitch. You could otherwise damage the vehi-
cle.
! Observe the following points when towing
with a tow rope:
R Secure the tow rope on the same side on
both vehicles.
R Make sure that the tow rope is not longer
than legally permitted. Mark the tow rope in
the middle, e.g. with a white cloth
(30 x 30 cm). This will make other road
users aware that a vehicle is being towed.
R Only secure the tow cable to the towing
eyes or, if available, to the trailer tow hitch.
R Observe the brake lamps of the towing
vehicle while driving. Always maintain a dis- 356
Towing away and tow-startingBreakdown assistance
tance a distance so that the tow rope does
not sag.
R Do not use steel cables or chains to tow
your vehicle. You could otherwise damage
the vehicle.
! Do not use the trailer tow hitch for recovery
or towing. Do not use the towing eye for
recovery. This could damage the vehicle. If in doubt, have the vehicle recovered using a
crane.
! When towing, pull away slowly and
smoothly. Pull the towed vehicle as straight as possible and not at an acute angle. If the trac-
tive power is too high, the vehicles could be
damaged.
When towing, it is preferable to use a rigid tow- ing bar as opposed to a tow rope. A rigid towing
bar helps to keep the tractive power low.
! To tow vehicles with KEYLESS-GO, use the
key instead of the Start/Stop button. The
automatic transmission may otherwise
switch to position Pwhen you open the driv-
er's or front-passenger door which could
damage the transmission.
! Vehicles with differential locks: make sure
the differential locks are in automatic mode.
When towing, the differential locks must not
be switched on. The transmission may other- wise be damaged.
! You may tow the vehicle for a maximum of
50km. A towing speed of 50 km/h must not
be exceeded.
For towing distances over 50 km, the entire
vehicle must be lifted up and transported.
Observe the legal requirements for the relevant countries when towing.
It is better to have the vehicle transported than
to have it towed.
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.
The battery must be connected and charged.
Otherwise, you:
R cannot turn the key to position 2in the igni-
tion lock
R cannot release the electric parking brake
R cannot shift the automatic transmission to
position N Deactivate the automatic locking feature before
towing the vehicle (Y page 253). You could oth-
erwise be locked out when pushing or towing
the vehicle.
Deactivate tow-away protection before the vehi-
cle is towed away (Y page 79). Fitting/removing the towing eye
Fitting the towing eye The mountings for the removable towing eyes
are located in the bumpers. They are at the front and rear behind covers :;.
X Remove the towing eye from the vehicle tool
kit (Y page 345).
X To open the cover at the front: press the
mark on cover :inwards in the direction of
the arrow.
X To open the cover at the rear: insert a flat,
blunt object into the cutout and lever
cover ;out of the bumper.
X Take cover :or; off the opening.
X Screw in the towing eye clockwise as far as it
will go and tighten it.
Removing the towing eye X
Loosen the towing eye and unscrew it.
X Position cover :or; in the bumper and
press the cover on until it engages.
X Place the towing eye in the vehicle tool kit. Towing away and tow-starting
357Breakdown assistance Z
Towing the vehicle with both axles on
the ground
The automatic transmission automatically shifts to position Pwhen you open the driver's or front-
passenger door or when you remove the key
from the ignition lock.
In order to ensure that the automatic transmis-
sion stays in position Nwhen towing away the
vehicle, you must observe the following points:
X Make sure that the vehicle is stationary.
X Turn the key to position 2in the ignition lock.
X Depress the brake pedal and keep it
depressed.
X Shift the automatic transmission to position
N.
X Leave the key in position 2in the ignition lock.
X Release the brake pedal.
X Release the electric parking brake.
X Switch on the hazard warning lamps
(Y page 122).
In order to signal a change of direction when
towing the vehicle with the hazard warning
lamps switched on, use the combination switch
as usual. In this case, only the turn signals for
the desired direction flash. When you reset the
combination switch, the hazard warning lamps
start flashing again. Transporting the vehicle
4MATIC vehicles/vehicles with auto-
matic transmission !
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.
All vehicles !
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 transport. X Turn the key to position 2in the ignition lock.
X Shift the automatic transmission to position
N.
As soon as the vehicle is loaded: X Secure the vehicle against rolling away by
applying the electric parking brake.
X Shift the automatic transmission to position
P.
X Turn the key to position 0in the ignition lock
and remove it.
X Secure the vehicle. Information for 4MATIC vehicles
! Vehicles with 4MATIC must not be towed
with the front or rear axle raised; otherwise,
the transmission may be damaged.
Vehicles with 4MATIC may either be towed away
with both axles on the ground or be loaded up
and transported.
If the vehicle has transmission damage or dam- age to the front or rear axle, have it transportedon a transporter 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 on-board
electrical system in the same way as when jump- starting (Y page 354).
Have the vehicle transported on a transporter or trailer. 358
Towing away and tow-startingBreakdown assistance