charging MERCEDES-BENZ R-Class 2012 W251 Owner's Manual

B
Back support see Lumbar support
Backup lamp
Changing bulbs .............................. 123
Display message ............................ 224
BAS (Brake Assist System) ................. 65
Basic settings see Settings
Battery (key)
Checking .......................................... 76
Battery (SmartKey)
Important safety notes ....................76
Replacing ......................................... 76
Battery (vehicle)
Charging ........................................ 312
Display message ............................ 227
Important safety notes ..................310
Jump starting ................................. 313
Belt
see Seat belts
Blind Spot Assist
Activating/deactivating .................210
Display message ............................ 230
Notes/function .............................. 189
Trailer towing ................................. 191
BlueTEC
Adding DEF .................................... 161
BlueTEC (DEF) .................................... 357
Brake Assist System see BAS (Brake Assist System)
Brake fluid
Display message ............................ 217
Notes ............................................. 359
Brake fluid level ................................ 286
Brake lamps Display message ............................ 223
Brakes
ABS .................................................. 65
BAS .................................................. 65
Brake fluid (notes) .........................359
Display message ............................ 214
Driving tips .................................... 166
Important safety notes ..................166
Maintenance .................................. 167
Parking brake ........................ 164, 168
Warning lamp ................................. 239Breakdown
see Flat tire
see Towing away
Bulbs
see Changing bulbs
C
California Important notice for retail
customers and lessees ....................22
Calling up a malfunction
see Display messages
Capacities
see Technical data
Car
see Vehicle
Care
Carpets .......................................... 294
Car wash ........................................ 288
Display ........................................... 292
Exterior lights ................................ 291
Gear or selector lever ....................293
Matte finish ................................... 290
Notes ............................................. 287
Paint .............................................. 290
Plastic trim .................................... 292
Power washer ................................ 289
Rear view camera .......................... 292
Roof lining ...................................... 294
Seat belt ........................................ 293
Seat cover ..................................... 293
Sensors ......................................... 291
Steering wheel ............................... 293
Tail pipes ....................................... 292
Trim pieces .................................... 293
Washing by hand ........................... 289
Wheels ........................................... 289
Windows ........................................ 291
Wiper blades .................................. 291
Wooden trim .................................. 293
Cargo compartment cover
Extending ....................................... 260
Notes/how to use .........................258
Cargo compartment enlargement
Full ................................................. 253
Important safety notes ..................253
Partial ............................................ 253
Index5

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 24).
Exterior lighting
Important safety notes
For reasons of safety, Mercedes-Benz
recommends that you drive with the lights
switched on even during the daytime. In some
countries, operation of the headlamps varies
due to legal requirements and self-imposed
obligations.
Information about driving abroad
Converting to symmetrical low beam
when driving abroad: switch the headlamps
to symmetrical low beam in countries in
which traffic drives on the opposite side of the
road to the country where the vehicle is
registered. This prevents glare to oncoming
traffic. Symmetrical lights do not illuminate
as large an area of the edge of the road.
Have the headlamps converted at a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center, as close to the border
as possible before driving in these countries.
Converting to asymmetrical low beam
after returning: have the headlamps
converted back to asymmetrical low beam at
a qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center, as soon as
possible after crossing the border again.
Light switch
Operation1 WLeft-hand standing lamps2XRight-hand standing lamps3$Lights off/daytime running lamps4ÃAutomatic headlamp mode/daytime
running lamps5 TParking lamps, license plate and
instrument cluster lighting6 LLow-beam/high-beam headlamps7RVehicles without front fog lamps:
rear fog lamp7 NVehicles with front fog lamps: front
fog lamp8 RVehicles with front fog lamps: rear
fog lamp
The turn signals, high-beam headlamps and
the high-beam flasher are operated using the
combination switch ( Y page 117).
! Switch off the parking lamps and standing
lamps when you leave the vehicle. This
prevents the battery from discharging.
The exterior lighting (except the parking/
standing lamps) switches off automatically if
you:
R remove the SmartKey from the ignition lock
R open the driver's door with the SmartKey
in position 0
If you hear a warning tone when you leave the
vehicle, the lights may still be switched on.
114Exterior lightingLights and windshield wipers

Rear overhead control panel (second row of seats)
:Switches the reading lamp on/off
Rear overhead control panel (third row of seats)
:p Switches the left-hand reading lamp
on/off;p Switches the right-hand reading
lamp on/off
Interior lighting control
Important notes
In order to prevent the vehicle's battery from
discharging, the interior lighting functions are
automatically deactivated after some time
except for when the SmartKey is in position
2 in the ignition lock.
Automatic interior lighting control
XTo switch on/off: press the | button.
When the automatic interior lighting
control is activated, the button is flush with
the overhead control panel.The interior lighting automatically switches
on if you:
R unlock the vehicle
R open a door
R remove the SmartKey from the ignition lock
The interior light is activated for a short while
when the SmartKey is removed from the
ignition lock. You can activate this delayed
switch-off using the on-board computer
( Y page 208).
Manual interior lighting controlXTo switch the front interior lighting on/
off: press the c button.XTo switch the rear interior lighting on/
off: press the v button.XTo switch the reading lamps on/off:
press the p button.
Crash-responsive emergency lighting
The interior lighting is activated automatically
if the vehicle is involved in an accident.
XTo switch off the crash-responsive
emergency lighting: press the hazard
warning lamp button.
or
XLock and then unlock the vehicle using the
key.
Replacing bulbs
Important safety notes
Xenon bulbs
If your vehicle is equipped with Xenon bulbs,
you can recognize this by the following: the
cone of light from the Xenon bulbs moves
from the top to the bottom and back again
when you start the engine. For this to be
observed, the lights must be switched on
before starting the engine.
Replacing bulbs119Lights and windshield wipersZ

The battery and the 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 or charging. Always have this work
performed at a qualified specialist workshop,
e.g. an authorized Mercedes-Benz Center.
i If 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 90).
R reset the panorama roof with power tilt/
sliding panel ( Y page 92).
R reset the function for automatically
folding the exterior mirrors in/out by
folding the mirrors out once
( Y page 110).
R reset the side windows ( Y page 89).
Charging the battery
GWARNING
Never charge a battery still installed in the
vehicle unless a battery charger 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.
A battery charger unit specially adapted for
Mercedes-Benz vehicles 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.
Charge the battery in accordance with the
separate instructions for the 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 313).
XOpen the hood ( Y page 282).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 313).XRead the battery charger's operating
instructions before charging the battery.312BatteryBreakdown assistance

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 36
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 37
.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.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 empty battery a little.
i Jumper cables and further information about jump-starting can be obtained from any
authorized Mercedes-Benz Center, for example.
XMake sure that the two vehicles do not touch.XApply the parking brake firmly.XShift the transmission to position P.36
Only vehicles with a gasoline engine.
37 Only vehicles with a gasoline engine.Jump-starting313Breakdown assistanceZ