Battery (vehicle)
12 V battery - important safety notes Plug-in hybrid: be sure to read the separate
operating instructions. You could otherwise 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 and ESP ®
,
see ( Y
page 66) and ( Y
page 70).
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.340
Battery (vehicle)
Breakdo wn assis tance
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 spe-
cialist workshop or a special
collection point for used bat-
teries.
! Have the battery regularly checked at a
qualified specialist workshop.
For more information, please contact a quali-
fied specialist workshop.
! Always have work on batteries carried out at
a qualified specialist workshop.
Should it, in exceptional circumstances, be
absolutely necessary to disconnect the 12-
volt battery yourself, please observe the fol-
lowing: R
Secure the vehicle to prevent it from rolling
away. R
Switch off the ignition. R
Disconnect the negative terminal first and
then the positive terminal.
The transmission is locked in position ]
after disconnecting the battery.
After the work has been done, install the bat-
tery and replace the cover of the positive ter-
minal clamp firmly.
Comply with safety precautions and take pro-
tective measures when handling batteries.
Risk of explosion.
Fire, open flames and smoking are
prohibited when handling the bat-
tery. Avoid creating sparks. Battery acid is caustic. Avoid contact
with skin, eyes or clothing.
Wear suitable protective clothing,
especially gloves, apron and face-
guard.
Rinse any acid spills immediately
with clear water. Contact a physician
if necessary.
Wear eye protection.
Keep children away.
Observe this Operator's Manual.
For safety reasons, Mercedes-Benz recom-
mends that you only use batteries which have
been tested and approved for your vehicle by
Mercedes-Benz. These batteries provide
increased impact protection to prevent vehicle
occupants from suffering acid burns should the
battery be damaged in the event of an accident.
In order for the battery to achieve the maximum
possible service life, it must always be suffi-
ciently charged.
Like other batteries, the vehicle battery may
discharge over time if you do not use the vehicle.
In this case, have the battery disconnected at a
qualified specialist workshop. However, you can
also charge the battery with a charger recom-
mended by Mercedes-Benz. Contact a qualified
specialist workshop for further information.
Have the battery condition of charge checked
more frequently if you use the vehicle mainly for
short trips or if you leave it standing idle for a
lengthy period. Consult a qualified specialist
workshop if you wish to leave your vehicle
parked for a long period of time.
Remove the SmartKey if you park the vehicle
and do not require any electrical consumers.
The vehicle will then use very little energy, thus
conserving battery power.
If the power supply has been interrupted, e.g. if
you reconnect the battery, you will have to: R
set the clock; see the Digital Operator's Man-
ualBattery (vehicle) 341
Breakdown assistance Z
On vehicles with a multimedia system and
navigation system, the clock is set automati-
cally. R
reset the function for folding the exterior mir-
rors in/out automatically, by folding the mir-
rors out once ( Y
page 106)
Charging the 12 V battery
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
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.
G WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing 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.
! Only use battery chargers with a maximum
charging voltage of 14.8 V.
! Only charge the battery using the jump-
starting connection point.
The jump-starting connection point is in the
engine compartment ( Y
page 342).X
Open the hood. X
Connect the battery charger to the positive
terminal and ground point in the same order
as when connecting the donor battery in the
jump-starting procedure ( Y
page 342).
Keep away from fire and open flames. Do not
lean over a battery. Never charge the battery if it
is still installed in the vehicle, unless you use a
battery charger which has been tested and
approved by Mercedes-Benz. A battery charger
unit specially adapted for Mercedes-Benz vehi-
cles and tested and approved by Mercedes-
Benz is available as an accessory. It permits the
charging of the battery in its installed position.
Contact an authorized Mercedes-Benz Center
for further information and availability. Read the
battery charger's operating instructions before
charging the battery.
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
jump-start the vehicle nor charge the battery.
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.
Jump-starting
Plug-in hybrid: be sure to read the separate Operator's Manual. You could otherwise fail to rec-
ognize dangers, e.g. due to high voltage.
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.
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 batteries. Wash away battery acid immediately with plenty of
clean water and seek medical attention.342
Jump-starting
Breakdown assistance
driver's or front-passenger door, which could
damage the transmission.
! Do not tow with sling-type equipment. This
could damage the vehicle.
! 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.
! 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
\\ when the vehicle is being towed.
The battery must be connected and charged.
Otherwise, you: R
cannot turn the SmartKey to position H in
the ignition lock R
cannot release the electric parking brake R
cannot shift the automatic transmission to
position \\
Disarm the automatic locking feature before the
vehicle is towed ( Y
page 239). You could other-
wise be locked out when pushing or towing the
vehicle.
If the vehicle is in a dangerous area, it can be
towed out of that area with both axles on the
ground. In this case, the towing distance must
not be greater than 165 ft (50 m) and must not
exceed a towing speed of 6 mph (10 km/h). For
longer distances, have the vehicle loaded and
transported. Installing/removing the towing eye
Installing the towing eye
The brackets for the screw-in towing eye are
located in the bumpers. They are at the front and
rear behind covers C D .X
Remove the towing eye from the vehicle tool
kit ( Y
page 335). X
To open the cover at the front: press the
mark on cover C 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 D out of the bumper. X
Take cover C or D off the opening.X
Screw in the towing eye clockwise as far as it
will go and tighten it.
Removing the towing eye X
Unscrew and remove the towing eye. X
Position cover C or D in the bumper and
press the cover on until it engages. X
Place the towing eye in the vehicle tool kit.
Towing a vehicle with both axles on
the ground
The automatic transmission shifts to position
] automatically when you open the driver's or
front-passenger door or when you remove the
SmartKey from the ignition lock.346
Towing and tow-starting
Breakdown assistance