air condition MERCEDES-BENZ R-Class 2012 W251 Owner's Guide

Display messagesPossible causes/consequences and M SolutionsBlind Spot Assist
Currently
Unavailable, See
Operator's ManualBlind Spot Assist is temporarily inoperative if:
R the sensors are dirty.
R its function is impaired due to heavy rain or snow.
R the radar sensor system is outside the operating temperature
range.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
The yellow 9 indicator lamps also light up in the exterior
mirrors.
Blind Spot Assist is operational again and the display message
disappears if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system detects that the sensors are fully available again.
R the radar sensor system is back within the operating
temperature range.
If the display message continues to be displayed:XClean the sensors ( Y page 291).XRestart the engine.Blind Spot Assist
InoperativeBlind Spot Assist is defective.
The yellow 9 indicator lamps also light up in the exterior
mirrors.XVisit a qualified specialist workshop.Cruise Control
InoperativeCruise control is defective.XVisit a qualified specialist workshop.Cruise Control
--- MPH A condition for activating cruise control has not been fulfilled.
You attempted to save a speed of less than 20 mph (30 km/h).XIf the situation allows, drive faster than 20 mph ( 30 km/h) and
save the speed.XCheck the activation conditions for cruise control
( Y page 170).DISTRONIC
--- MPH An activation condition for DISTRONIC is not fulfilled.XCheck the activation conditions for DISTRONIC ( Y page 173).DISTRONIC
OverrideDISTRONIC is no longer controlling the speed of the vehicle.XTake your foot off the accelerator pedal.230Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsDISTRONIC
InoperativeDISTRONIC is defective or the display has failed.XVisit a qualified specialist workshop.DISTRONIC
Currently
Unavailable See
Operator's ManualDISTRONIC is deactivated and is temporarily inoperative if:
R the DISTRONIC cover in the radiator grill is dirty.
R its function is impaired due to heavy rain, snow or fog.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
R the radar sensor system has not detected any vehicles or
stationary objects, e.g. traffic signs, for a long time.
R the system is outside the operating temperature range.
DISTRONIC becomes available again and the display message
disappears if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system detects that the sensors are fully available again.
R the system is within the operating temperature range.
If the display message continues to be displayed:XClean the DISTRONIC cover in the radiator grill ( Y page 291).XRestart the engine.GWARNING
DISTRONIC cannot take weather conditions into account. Switch off DISTRONIC or do not turn
it on if the sensor is dirty or visibility is diminished as a result of snow, rain or fog. The distance
control may be impaired even before the system is able to detect a dirty sensor. The DISTRONIC
Currently Unavailable See Operator's Manual message will be displayed in the
multifunction display and DISTRONIC will be turned off.
Tires
GWARNING
Do not drive with a flat tire. A flat tire affects the ability to steer or brake the vehicle. You may
lose control of the vehicle. Continued driving with a flat tire will cause excessive heat build-up
and possibly a fire.
GWARNING
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires wear excessively and/or unevenly, adversely affect
handling and fuel economy, and are more likely to fail from being overheated.
Display messages231On-board computer and displaysZ

Stowage compartments under the
armrest
The stowage compartment and the stowage
tray can be opened separately.
i In vehicles with the Rear Seat
Entertainment System, a DVD player is
installed in the stowage compartment; see
the separate operating instructions.XTo open the stowage tray: press release
button : and fold the armrest upwards.XTo open the stowage compartment:
press release button ; and fold the
armrest upwards.=Stowage tray?Coin holder
i The Roadside Assistance
º (Y page 272) and MB info call
E (Y page 272) buttons are in the
stowage tray = under the armrest.
Stowage compartments in the rear
Stowage compartments above the center
air vents, 2nd row of seats
Depending on the equipment in the vehicle, a
control panel may be installed instead of the
upper stowage compartment, e.g. if the
vehicle has rear-compartment air
conditioning for the 2nd and 3rd rows of
seats.
Stowage compartment in the center
console, 2nd row of seats
XTo open: press the release button under
the armrest and fold the armrest upwards.
Stowage compartments in the 3rd row of
seats
There is a stowage compartment in the side
trim on both sides. In vehicles with rear-
compartment air conditioning (2nd and 3rd
row of seats), a swiveling side air vent is
installed instead of the stowage
compartment.
250Stowage areasStowing and features

cleaning. Braking heats the brake discs and
the brake pads/linings, thus drying them.
The vehicle can then be parked.
Cleaning the paintwork
Scratches, corrosive deposits, areas affected
by corrosion and damage caused by
inadequate care cannot always be completely
repaired. In such cases, visit a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
XRemove impurities immediately, where
possible, whilst avoiding rubbing too hard.XSoak insect remains with insect remover
and rinse off the treated areas afterwards.XSoak bird droppings with water and rinse
off the treated areas afterwards.XRemove coolant, brake fluid, tree resin,
oils, fuels and greases by rubbing gently
with a cloth soaked in petroleum ether or
lighter fluid.XUse tar remover to remove tar stains.XUse silicone remover to remove wax.
! Do not affix:
R stickers
R films
R magnetic plates or similar items
to painted surfaces. You could otherwise
damage the paintwork.
If water no longer forms "beads" on the paint
surface, use the paint care products
recommended and approved by Mercedes-
Benz. This is the case approximately every
three to five months, depending on the
climate conditions and the care product used.
If dirt has penetrated the paint surface or the
paint has become dull, the paint cleaner
recommended and approved by Mercedes-
Benz should be used.
Do not use these care products in the sun or
on the hood while the hood is hot.
XUse a suitable touch-up stick, e.g. MB
Touch-Up Stick, to correct smaller areas of
paint damage quickly and provisionally.
Matte finish care
If your vehicle has a clear matte finish,
observe the following instructions in order to
avoid damage to the paintwork due to
incorrect care.
These notes also apply to light alloy wheels
with a clear matte finish.
! Never polish the vehicle or the light alloy
wheels. Polishing causes the finish to
shine.
! The following may cause the paint to
become shiny and thus reduce the matte
effect:
R Vigorous rubbing with unsuitable
materials.
R Frequent use of car washes.
R Washing the vehicle in direct sunlight.
! Never use paint cleaner, buffing or
polishing products, or gloss preserver, e.g.
wax. These products are only suitable for
high-gloss surfaces. Their use on vehicles
with matte finish leads to considerable
surface damage (shiny, spotted areas).
Always have paintwork repairs performed
at a qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center.
! Do not use wash programs with a hot wax
treatment under any circumstances.
i The vehicle should preferably be washed
by hand using a soft sponge, car shampoo
and plenty of water.
i Use only insect remover and car shampoo
from the range of recommended and
approved Mercedes-Benz care products.
290CareMaintenance and care

Flat tire
Preparing the vehicle
Your vehicle may be equipped with a
collapsible spare wheel or MOExtended tires
(tires with run-flat properties) ( Y page 309).
i Vehicle preparation is not necessary on
vehicles with MOExtended tires.
i Vehicles equipped with MOExtended tires
are not equipped with a TIREFIT kit at the
factory. It is therefore recommended that
you additionally equip your vehicle with a
TIREFIT kit if you mount tires that do not
feature run-flat properties, e.g. winter tires.
A TIREFIT kit can be obtained from an
authorized Mercedes-Benz Center.
XVehicles with the AIRMATIC package: make
sure that highway level is selected
( Y page 180).XStop the vehicle as far away as possible
from traffic on solid, non-slippery and level
ground.XSwitch on the hazard warning lamps.XFirmly depress the parking brake.XBring the front wheels into the straight-
ahead position.XMove the DIRECT SELECT lever to P.XSwitch off the engine.XVehicles without KEYLESS-GO: remove
the SmartKey from the ignition lock.XVehicles with KEYLESS-GO: open the
driver's door.
The on-board electronics have status 0,
which is the same as the SmartKey having
been removed.XVehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock
( Y page 145).XAll occupants must get out of the vehicle.
Make sure that they are not endangered as
they do so.XMake sure that no one is near the danger
area while a wheel is being changed.Anyone who is not directly assisting in the
wheel change should, for example, stand
behind the barrier.XGet out of the vehicle. Pay attention to
traffic conditions when doing so.XClose the driver's door.
i Only operate the tire inflation compressor
using the socket in the footwell of the
second row of seats ( Y page 268), even if
the ignition is turned off.
An emergency cut-off ensures that the on-
board electrical system voltage does not
drop too low. If the on-board electrical
system voltage is too low, power to the
sockets is automatically cut off. This
ensures that there is sufficient power to
start the engine.
TIREFIT kit
Using the TIREFIT kit
You can use the TIREFIT kit to seal small
punctures, particularly those in the tire tread.
You can use TIREFIT at outside temperatures
down to -4 ‡ (-20 †).
GWARNING
TIREFIT is a limited repair device. TIREFIT
cannot be used for cuts or punctures larger
than approximately 0.16 in (4 mm) and tire
damage caused by driving with extremely low
tire inflation pressure, or on a flat tire, or a
damaged wheel.
Do not drive the vehicle under such
circumstances.
Contact the nearest authorized Mercedes-
Benz Center for assistance or call Roadside
Assistance.
XDo not remove any foreign objects which
have penetrated the tire, e.g. screws or
nails.XRemove the tire sealant bottle, the
accompanying "max. 80 km/h" sticker and
the tire inflation compressor from theFlat tire299Breakdown assistanceZ

and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver's door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
You will find a table of recommended tire
pressures on the Tire and Loading
Information placard on the B-pillar on the
driver's side ( Y page 333). You will find a
table of tire pressures for various operating
conditions on the inside of your vehicle's fuel
filler flap.
To test tire pressure, use a suitable tire
pressure gauge. The outer appearance of a
tire does not permit any reliable conclusion
about the tire pressure. On vehicles equipped
with the electronic tire pressure monitoring
system, the tire pressure can be checked
using the on-board computer.GWARNING
Should the tire pressure drop repeatedly:
R check the tire for foreign bodies.
R check whether the wheel is losing air or the
valve is leaking.
R make sure that only a valve cap approved
by Mercedes-Benz is installed on the tire
valve.
Tire pressures that are too low have a
negative effect on vehicle safety, which could
lead you to cause an accident.
Only correct tire pressures when the tires are
cold. The tires are cold when the vehicle has
been parked for at least three hours or driven
for less than 1 mile (1.6 km). The tire
temperature changes depending on the
outside temperature, the vehicle speed and
the tire load. If the tire temperature changes
by 18 ‡ (10 †), the tire pressure changes by
approximately 10 kPa (0.1 bar/1.5 psi). Take
this into account when checking the pressure
of warm tires and only correct the tire
pressure if it is too low for the current
operating conditions. If you check the tire
pressure when the tires are warm, the
resulting value will be higher than if the tires
were cold. This is normal. Do not reduce the
tire pressure to the value specified for cold
tires. The tire pressure would otherwise be
too low.
Observe the recommended tire pressure
specifications for cold tires on the Tire and
Loading Information placard on the B-pillar on
the driver's side.
i The specifications given on the following
Tire and Loading Information placard are
examples. Tire pressure specifications are
vehicle-specific and may deviate from the
data shown here. The tire pressures
applicable to your vehicle can be found on
the Tire and Loading Information placard on
your vehicle.
You will find recommended tire pressure
specifications : for cold tires and for a fully
loaded vehicle on the Tire and Loading
Information placard. The tire pressure
information is applicable to all tires mounted
at the factory.
326Tire pressureWheels and tires

Important notes on tire pressureGWARNING
If the tire pressure drops repeatedly, check
the tires for punctures from foreign objects
and/or whether air is leaking from the valves
or from around the rim.
The tire temperature and pressure increase
when the vehicle is in motion. This is
dependent on the driving speed and the load.
If you wish to drive at high speeds of
100 mph (160 km/h) or higher when this is
allowed, use the tire pressure table on the
inside of the fuel filler flap to set the correct
tire pressures when the tires are cold. If the
tire pressure is not set correctly, this can lead
to an excessive build up of heat and a sudden
loss of pressure.
For further information, consult a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
i Driving comfort can be impaired if the tire
pressure value recommended in the tire
pressure table for speeds over
100 mph(160 km/h) is adopted.
Make sure that the tire pressure for normal
speeds is adopted again.
Additional specifications of tire pressure
values for loads can also be found on the tire
pressure table on the inside of the fuel filler
flap.
The tire pressure for emergency spare wheels
can be found:
R printed in yellow on the rim of the
emergency spare wheel
R in the "Wheel and tire combinations"
section ( Y page 347) in this manual
R on the Tire and Loading Information placard
on the B-pillar on the driver's side.
i Specifications shown in the examples of
tire pressure tables are for illustration
purposes only. Tire pressure specifications
are vehicle-specific and may deviate from
the data shown here. Tire pressure
specifications applicable to your vehicle
are located in your vehicle's tire pressure
table.
Unless stated otherwise, the tire pressures
specified on the fuel filler flap apply for all
tires approved for this vehicle.
Tire pressure table for all tires permitted for this
vehicle by the factory (example)
If a tire size precedes a tire pressure, the tire
pressure information following is only valid
for that tire size. The load conditions "partially
laden" and "fully laden" are defined in the
table for different numbers of passengers and
amounts of luggage. The actual number of
seats may differ.
Tire pressure table with tire dimensions (example)
Some tire pressure tables show only the rim
diameters instead of the full tire size, e.g.
R18 . The rim diameter is part of the tire
dimension and can be found on the sidewall
of the tire ( Y page 340).
Tire pressure327Wheels and tiresZ

Rim
This is the part of the wheel on which the tire
is mounted.
GAWR (Gross Axle Weight Rating)
The GAWR is the maximum permissible axle
weight. The actual load on an axle must never
exceed the gross axle weight rating. The
gross axle weight rating can be found on the
vehicle identification plate on the B-pillar on
the driver's side.
Tire speed rating
The tire speed rating is part of the tire
identification. It specifies the speed range for
which the tire is approved.
GTW (Gross Trailer Weight)
The GTW is the weight of a trailer including
the weight of the load, luggage, accessories
etc. on the trailer.
GVW (Gross Vehicle Weight)
The gross vehicle weight comprises the
weight of the vehicle including fuel, tools, the
spare wheel, accessories installed,
occupants, luggage and the drawbar
noseweight if applicable. The gross vehicle
weight must not exceed the gross vehicle
weight rating GVWR as specified on the
vehicle identification plate on the B pillar on
the driver's side.
GVWR (Gross Vehicle Weight Rating)
The GVWR is the maximum permissible gross
weight of a fully loaded vehicle (the weight of
the vehicle including all accessories,
occupants, fuel, luggage and the drawbar
noseweight if applicable). The gross vehicle
weight rating is specified on the vehicle
identification plate on the B-pillar on the
driver's side.
Maximum loaded vehicle weight
The maximum weight is the sum of the curb
weight of the vehicle, the weight of the
accessories, the total load limit and the
weight of the optional equipment installed at
the factory.
Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa is the
equivalent of 1 psi. Another unit for tire
pressure is bar. There are 100 kilopascals
(kPa) to 1 bar.
Load index
In addition to the load bearing index, the load
index may also be imprinted on the sidewall
of the tire. This specifies the load bearing
capacity more precisely.
Curb weight
The weight of a vehicle with standard
equipment including the maximum capacity
of fuel, oil and coolant. It also includes the air-
conditioning system and optional equipment
if these are installed in the vehicle, but does
not include passengers or luggage.
Maximum load rating
The maximum load rating in kilograms or
pounds is the maximum weight for which a
tire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire.
344Definition of terms for tires and loadingWheels and tires

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).
Genuine Mercedes-Benz parts
All Mercedes-Benz Centers maintain a supply
of genuine Mercedes-Benz parts for
necessary service and repair work. In
addition, strategically located parts delivery
centers provide for quick and reliable parts
service.
There are more than 300,000 different
genuine Mercedes-Benz parts available for
Mercedes-Benz models.
Genuine Mercedes-Benz parts are subject to
strict quality control. Each part has been
specially developed, manufactured or
selected for Mercedes-Benz vehicles and
fine-tuned for them.
Therefore, only genuine Mercedes-Benz parts
should be used.
GWARNING
Driving safety may be impaired if non-
approved parts, tires and wheels or safety-
relevant accessories are used.
This could lead to malfunctions in safety-
relevant systems, e.g. the brake system. This
could cause you to lose control of your vehicle
and cause an accident.
For this reason, Mercedes-Benz recommends
that you use genuine Mercedes-Benz parts or
parts of equal quality. Only use tires, wheels
and accessories that have been specifically
approved for your vehicle.
! Air bags and Emergency Tensioning
Devices, as well as control units and
sensors for these restraint systems may be
installed in the following areas of your
vehicle:
R doors
R door pillars
R door sills
R seats
R dashboard
R instrument cluster
R center console
Do not install accessories such as audio
systems in these areas. Do not carry out
repairs or welding. You could impair the
operating efficiency of the restraint
systems.
Have aftermarket accessories installed at
a qualified specialist workshop. Mercedes-
Benz recommends that you use an
authorized Mercedes-Benz Center for this
purpose.HEnvironmental note
Daimler AG also supplies reconditioned major
assemblies and parts which are of the same
quality as new parts. They are covered by the
same Limited Warranty entitlements as new
parts.
Always specify the vehicle identification
number (VIN) ( Y page 353) and the engine
number ( Y page 354) when ordering genuine
Mercedes-Benz parts.
Warranty
The Service and Warranty Information
booklet contains detailed information about
the warranties covering your vehicle.
352WarrantyTechnical data

CapacitiesVehicle modelCapacityFuel, coolant,
lubricants etc.Engine oil and
filterR 350 BlueTEC9.0 US qt (8.5 l)Approved engine
oilsR 3507.9 US qt (7.5 l)Cooling systemAll modelsApprox. 10.0 US qt (9.5 l)MB 326.0 corrosion
inhibitor/antifreeze
agentTank capacityAll models21.1 US gal (80.0 l)Gasoline engines:
premium-grade
unleaded gasoline
(at least 91 octane,
average value
between 96 RON/
86 MON)
Diesel engines:
ULTRA-LOW
SULFUR HIGHWAY
DIESEL FUEL (ULSD,
maximum sulfur
content 15 ppm)ReserveAll modelsApprox. 3.4 US gal (13.0 l)DEF tankR 350 BlueTEC7.5 US gal (28.2 l)DEF in accordance
with ISO 22241Air-
conditioning
systemAll models—Refrigerant R134a
and special PAG
lubricant (never
R 12)Windshield/
headlamp
cleaning
systemAll models7.4 US qt (7.0 l)MB windshield
washer
concentrate 45
( Y page 360)
Mixing ratio for
washer fluid
( Y page 360)45
Mixed with water or premixed washer fluid with antifreeze protection.Service products and capacities355Technical dataZ