Battery MERCEDES-BENZ R-Class 2011 W251 Owner's Guide

Immediately rinse acid
splashes off with clean
water. Consult a doctor if
necessary.Wear eye protection.Keep children away.Observe this Operator's
Manual.HEnvironmental note
Do not dispose of batteries in the household
rubbish. Dispose of defective batteries in an
environmentally responsible manner. Take
them to an authorized Mercedes-Benz Center
or to a special collection point for old
batteries.
GWarning
Failure to follow these instructions can result
in severe injury or death.
Never lean over batteries while connecting.
You might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking etc.
GWarning
Do not place any metal objects on the battery
as this could result in a short circuit.
Use leak-proof batteries only to avoid the risk
of acid burns in the event of an accident.
Take care that you do not become statically
charged, e.g. by wearing synthetic clothing or
rubbing against textiles. For this reason, you
also should not pull or push the battery over
carpets or other synthetic materials.
Never touch the battery first. First, touch the
outside body of the vehicle in order to release
any possible electrostatic charges.
Do not rub the battery with rags or cloths. The
battery could explode if touched due to
electrostatic charge or due to spark
formation.
! Switch off the engine and remove the
SmartKey before disconnecting the
terminal clamps from the battery. On
vehicles with KEYLESS-GO, make sure that
the ignition is switched off. Check that all
the indicator lamps in the instrument
cluster are off. You may otherwise destroy
electronic components, such as the
alternator.
! 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, e.g. an authorized Mercedes-
Benz Center. You can also charge the
battery with a charger recommended by
Mercedes-Benz. Contact an authorized
Mercedes-Benz Center for further
information.
The battery, breather hose and cover of the
positive terminal clamp must be installed
securely during operation.
i 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.
Mercedes-Benz recommends that you do not
carry out work on batteries yourself, e.g.
removing, charging or replacing. Always have
this work performed at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
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iIf the power supply has been interrupted,
e.g. if the battery has been reconnected,
you must carry out the following tasks:
R set the clock ( Y page 206)
On vehicles with COMAND and a
navigation system, the clock is set
automatically.
R reset the sliding sunroof ( Y page 93)
R reset the panorama roof with power tilt/
sliding panel ( Y page 94)
R reset the function for folding the exterior
mirrors in/out automatically by folding
the mirrors out once ( Y page 112)
R reset the side windows ( Y page 88)
Charging the battery
GWarning
Never charge a battery while still installed in
the vehicle unless the accessory battery
charge unit approved by Mercedes-Benz is
being used. Gases may escape during
charging and cause explosions that may
result in paint damage, corrosion or personal
injury.
An accessory battery charge unit specially
adapted for Mercedes-Benz vehicles and
tested and approved by Mercedes-Benz is
available. It permits the charging of the
battery in its installed position. Contact an
authorized Mercedes-Benz Center for
information and availability.
Charge the battery in accordance with the
separate instructions for the accessory
battery charger.
GWarning!
There is a risk of acid burns during the
charging process due to the gases which
escape from the battery. Do not lean over the
battery during the charging process.
GWarning!
Battery acid is caustic. Avoid contact with the
skin, eyes or clothing.
! Only charge the installed battery with a
battery charger which has been tested and
approved by Mercedes-Benz. These battery
chargers allow the battery to be charged
while still installed.
! 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 311).XOpen the hood ( Y page 278).XConnect the battery charger to the positive
terminal and earth point in the same order
as when connecting the donor battery in
the jump-starting procedure
( Y page 311).310BatteryRoadside Assistance
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Jump-startingGWarning
Failure to follow these directions will cause damage to the electronic components, and can lead
to a battery explosion and severe injury or death.
Never lean over batteries while connecting or jump starting. You might get injured.
Battery fluid contains sulfuric acid. Do not allow this fluid to come in contact with eyes, skin or
clothing. In case it does, immediately flush affected area with water, and seek medical help if
necessary.
A battery will also produce hydrogen gas, which is flammable and explosive. Keep flames or
sparks away from battery, avoid improper connection of jumper cables, smoking, etc.
Attempting to jump start a frozen battery can result in it exploding, causing personal injury.
Read all instructions before proceeding.
! Avoid repeated and lengthy starting attempts. Otherwise, non-combusted fuel may
damage the catalytic converter 41
and create a risk of fire.
Do not use a rapid-charging device to start the engine.
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.
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:
XThe 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.XOnly jump-start the vehicle when the engine is cold and the catalytic converter system has
cooled down 42
.XDo not start the engine if the battery is frozen. Let the battery thaw first.XJump-starting may only be performed from batteries with a nominal voltage of 12 V.
If you jump-start using a battery with higher voltage, it may damage the electrical systems
of the vehicle.XOnly use jumper cables which have a sufficient cross-section and insulated terminal clamps.XMake sure that the jumper cables cannot come into contact with parts, such as the pulley
or the fan. These parts move when the engine is started and while it is running.XIf 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 a little.
i Jumper cables and further information about jump-starting can be obtained from any
authorized Mercedes-Benz Center.
XMake sure that the two vehicles do not touch.XApply the parking brake firmly.41 Only vehicles with a gasoline engine.
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XShift the transmission to position P.XSwitch off all electrical consumers (e.g. radio, blower etc.).XOpen the hood ( Y page 278).
Position number C identifies the charged battery of the other vehicle or an equivalent jump-
starting device.
! Never swap the terminal connections.
XLift up cover : of positive terminal ; in the direction of the arrow.XConnect positive terminal ; on your vehicle to positive terminal = of donor battery C
using the jumper cable, beginning with your own battery.XStart the engine of the donor vehicle and run it at idling speed.XRemove cover A from earth point B.XConnect negative terminal ? of donor battery C to earth point B of your vehicle using
the jumper cable, connecting the jumper cable to donor battery C first.XStart the engine.XFirst remove the jumper cable from earth point B and negative terminal ?, then from
positive terminal ; and positive terminal =, each time disconnecting from the battery on
your own vehicle first.XHave the battery checked at a qualified specialist workshop, e.g. an authorized Mercedes-
Benz Center.312Jump-startingRoadside Assistance
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Towing away
Important safety guidelines
GWarning
With the engine not running, there is no power
assistance for the brake and steering
systems. In this case, it is important to keep
in mind that a considerably higher degree of
effort is necessary to brake and steer the
vehicle. Adapt your driving accordingly.
If possible, have the vehicle transported by a
suitable vehicle with both axles raised,
instead of having it towed.
If it is not possible to load the vehicle due to
external conditions, tow the vehicle with both
axles on the ground the shortest distance
possible to a place where it is possible to load
the vehicle.
! When towing, pull away slowly and
smoothly. If the tractive power is too high,
the vehicles could be damaged.
! Do not use the towing eye for recovery,
as this could damage the vehicle. If in
doubt, recover the vehicle with a crane.
! You must not start the vehicle by tow-
starting. This could otherwise damage the
automatic transmission.
! Do not tow with sling-type equipment.
This could damage the vehicle.
! Only secure the tow rope or tow bar at the
towing eyes, or the trailer tow hitch, if
available. You could otherwise damage the
vehicle.
! When towing vehicles with KEYLESS-GO,
use the key instead of the Start/Stop
button. Otherwise, the automatic
transmission may shift to position P when
the driver's or front-passenger door are
opened, which could lead to damage to the
transmission.
! The vehicle must not be towed with raised
front or rear axles. This could otherwise
damage the transmission.
The battery must be connected and charged
when towing. Otherwise, you cannot switch
on the ignition and select N with the
automatic transmission.
i Switch the automatic door lock off before
towing ( Y page 208). Otherwise, you could
lock yourself out of the vehicle when
pushing or towing the vehicle.
Installing the towing eye
Vehicles with a trailer tow hitch: if possible,
fasten the towing mechanism to the trailer
tow hitch ( Y page 193).
XRemove the towing eye and the lug wrench
(if supplied) from the vehicle tool kit
( Y page 294).GWarning
In order to avoid possible serious burns or
injury, use extreme caution when removing
the rear cover, because the rear exhaust pipe
is extremely hot.
The mountings for the removable towing eyes
are located in the bumpers. They are at the
front and at the rear, behind the covers.
XPress the mark on cover : inwards, in the
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Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the maximum axle load of one axle
by two.
PSI (pounds per square inch)
Standard unit of measurement for tire
pressure.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tire pressure
Pressure inside the tire applying an outward
force to every square inch of the tire's
surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold. For this,
the vehicle must have been stationary for at
least three hours or not have traveled more
than 1.6 km (1 mile) in this time.
Tire tread
The part of the tire that comes into contact
with the road.
Tire bead
The tire bead contains steel wire which is
bound by steel cords that hold the tire on the
wheel rim.
Sidewall
The part of the tire between the tread and the
tire bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
part and more than 2.3 kilograms (5 lbs).
These optional extras, such as high-
performance brakes, level control, a roof rack
or a high-performance battery, are not
included in the unladen weight and the weight
of the accessories.
TIN (Tire Identification Number)
A unique identification number which can be
used by a tire manufacturer to identify tires,
for example for a product recall, and thus
identify the purchasers. The TIN is made up
of the manufacturer's identity code, tire size,
tire type code and the manufacturing date.
Load bearing index
The load bearing index (also load index) is a
code that contains the maximum load bearing
capacity of a tire.
Traction
Traction is the result of friction between the
tires and the road surface.
TWR (permissible trailer drawbar
noseweight)
The TWR is the maximum permissible weight
that the ball coupling of the trailer tow hitch
can support.
Wear indicator
Narrow bars (tread wear bars) that are
distributed over the tire tread. If the tire tread
is level with the bars, the wear limit of 1
/ 16 in
(1.6 mm) has been reached.
342Definitions for tires and loadingTires and wheels
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