Jump-starting
For the jump-starting procedure, use only the jump-starting connection point in the engine com-
partment, consisting of a positive terminal and a ground point.
GWARNING
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 batteries. Wash away battery acid immediately with plenty of
clean water and seek medical attention.
GWARNING
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 ven-
tilation while charging and jump-starting. Do not lean over a battery.
GWARNING
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.
RMake sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
RNever place metal objects or tools on a battery.
RIt is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
RWhen jump-starting, make sure that the battery poles with identical polarity are connected.
RIt is particularly important to observe the described order when connecting and disconnecting
the jumper cables.
RNever connect or disconnect the battery terminals while the engine is running.
GWARNING
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.
!Avoid repeated and lengthy starting attempts. Otherwise, the catalytic converter could be
damaged by the non-combusted fuel.
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.
274Jump-starting
Breakdown assistance
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:
RThe 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.
RYou may only jump-start the vehicle when the engine and exhaust system are cold.
ROnly jump-start from batteries with a 12 V voltage rating.
ROnly use jumper cables which have a sufficient cross-section and insulated terminal clamps.
RIf 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.
RMake sure that the two vehicles do not touch.
Make sure that:
Rthe jumper cables are not damaged.
Rwhen the jumper cables are connected to the battery, uninsulated sections of the terminal clamp
do not come into contact with other metal sections.
Rthe jumper cables cannot come into contact with parts which can move when the engine is
running, such as the V-belt pulley or the fan.
XApply the parking brake firmly.
XShift the transmission to position P.
XMake 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 0in the ignition lock and remove it
(
Ypage 122).
XSwitch off all electrical consumers, e.g. rear window defroster, lighting, etc.
XOpen the hood.
Position number Bidentifies the charged battery of the other vehicle or an equivalent jump-starting
device.
XSlide cover :of positive terminal ;in the direction of the arrow.
XConnect positive terminal ;on your vehicle to positive terminal =of donor battery Busing the
jumper cable, always begin with positive terminal ;on your own vehicle first.
Jump-starting275
Breakdown assistance
Z
XStart the engine of the donor vehicle and run it at idling speed.
XConnect negative terminal?of donor battery Bto ground point Aof your vehicle using the
jumper cable, connecting the jumper cable to battery of other vehicle Bfirst.
XStart the engine.
XBefore disconnecting the jumper cables, let the engine run for several minutes.
XFirst, remove the jumper cables from ground point Aand negative terminal ?, then from pos-
itive clamp ;and positive terminal =. Begin each time at the contacts on your own vehicle first.
XClose cover:of positive clamp ;after removing the jumper cables.
XHave the battery checked at a qualified specialist workshop.
Jump-starting is not considered to be a normal operating condition.
iJumper cables and further information regarding jump-starting can be obtained at any qualified
specialist workshop.
Towing and tow-starting
Important safety notes
GWARNING
Functions relevant to safety are restricted or
no longer available if:
Rthe engine is not running.
Rthe brake system or the power steering is
malfunctioning.
Rthere 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.
GWARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissible
gross weight of your vehicle, the:
Rthe towing eye could detach itself
Rthe 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 (
Ypage 307).
!When COLLISION PREVENTION ASSIST
PLUS, DISTRONIC PLUS 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:
Rwhen towing the vehicle
Rin the car wash
!Only secure the tow rope or tow bar at the
towing eyes. Otherwise, the vehicle could be
damaged.
!Do not use the towing eye for recovery, 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.
!Do not tow with sling-type equipment. This
could damage the vehicle.
!On vehicles with KEYLESS-GO, use the
SmartKey instead of the Start/Stop button.
Turn the SmartKey to position 2in the ignition
lock and shift the automatic transmission to
N. Then, turn the SmartKey back to 0and
leave it in the ignition lock.
!The vehicle can be towed a maximum of
30 miles (50km). The towing speed of 30 mph
(50 km/h) must not be exceeded.
276Towing and tow-starting
Breakdown assistance
If the vehicle has to be towed more than
30 miles (50km), the entire vehicle must be
raised and transported.
!If you tow or tow-start another vehicle, its
weight must not exceed the maximum per-
missible gross vehicle weight of your vehicle.
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.
The battery must be connected and charged.
Otherwise, you:
Rcannot turn the SmartKey to position 2in the
ignition lock
Rcannot shift the automatic transmission to
position N
In the event of damage to the electrical sys-
tem
If the battery is defective, the automatic trans-
mission 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
(
Ypage 274).
Have the vehicle transported on a transporter or
trailer.
Disarm the automatic locking feature before the
vehicle is towed (
Ypage 79). You could other-
wise be locked out when pushing or towing the
vehicle.
Installing/removing the towing eye
Installing the towing eye
GWARNING
The exhaust tail pipe may be very hot. There is
a risk of burns when removing the rear cover.
Do not touch the exhaust pipe. Take particular
care when removing the rear cover.
The mountings for the removable towing eyes
are located in the bumpers. They are at the rear
and at the front, under covers :.
XRemove the towing eye from the vehicle tool
kit (Ypage 266).
XPress the mark on cover:inwards in the
direction of the arrow.
XTake cover :off the opening.
XScrew in the towing eye clockwise as far as it
will go and tighten it.
Removing the towing eye
XUnscrew and remove the towing eye.
XPosition cover :on top of the bumper and
press it in at the bottom until it engages.
XPlace the towing eye in the vehicle tool kit.
Towing a vehicle with both axles on
the ground
It is important that you observe the safety
instructions when towing away your vehicle
(
Ypage 276).
XTurn the SmartKey to position 2in the ignition
lock.
XWhen the vehicle is stationary, depress the
brake pedal and keep it depressed.
XShift the automatic transmission to position
N.
Towing and tow-starting277
Breakdown assistance
Z
XReleaseth ebrak epedal .
XReleas eth eparking brake.
In order to signal achang eof direction when
towin gth evehicl ewit hth ehazard warning
lamp sswitched on ,use th ecombination switch
as usual. In this case, only th eindicator lamp s
for th edirection of travel flash. Afte rresetting
th ecombination switch ,th ehazard warning
lamp start sflashin gagain .
Towing the vehicle with the rear axle
raised
!
Vehicles wit h4MATIC mus tno tbe towed
wit heither th efron tor th erear axl eraised, as
doin gso will damag eth etransmission .
!Vehicles withautomatic transmission mus t
no tbe towed wit hth erear axl eraised. The
vehicle/traile rcombination may otherwise
swerve or eve nrol lover.
Transporting the vehicle
4MATIC vehicles/vehicles with auto-
matic transmission
!When th evehicl eis loade dfor transport, th e
fron tand rear axles mus tbe stationary and on
th esam etransportation vehicle. Positioning
ove rth econnection poin tof th etranspor t
vehicl eis no tpermitted. The driv etrain may
otherwise be damaged.
All vehicles
!You may only secure th evehicl eby th e
wheels, no tby part sof th evehicl esuc has
axl eor steering components. Otherwise, th e
vehicl ecould be damaged. The towin
geye can be used to pull th evehicl e
onto atrailer or transporte rfor transporting pur-
poses.
XTurn th eSmartKey to position 2in th eignition
lock.
XShift th eautomatic transmission to position
N .
As soon as th evehicle ha sbeen loaded:
XPreven tth evehicl efrom rollin gaway by
applyin gth eparking brake.
XShift th eautomatic transmission to posi-
tion P.
XTurn th eSmartKey to position 0in th eignition
loc kand remove it .
XSecureth evehicle.
Notes on 4MATIC vehicles
!
Vehicles wit h4MATIC mus tno tbe towed
wit heither th efron tor th erear axl eraised, as
doin gso will damag eth etransmission .
If th evehicl ehas transmission damag eor dam-
age to th efron tor rear axle, hav eit transporte d
on atransporte ror trailer .
In th eevent of damage to th eelectrical sys -
tem
If th ebattery is defective, th eautomatic trans -
mission will be locke din position P.To shif tth e
automatic transmission to position N,you mus t
provide powe rto th evehicle's electrical system
in th esam eway as when jump-starting
(
Ypage 274).
Hav eth evehicl etransporte don atransporte ror
trailer .
Tow-starting (emergency engine
starting)
!
Vehicles wit hautomatic transmission mus t
no tbe started by tow-starting .This could oth-
erwise damag eth etransmission .
iYou can findinformation on "Jump-starting "
under (Ypage 274).
278Towing and tow-starting
Breakdown assistance