air condition MERCEDES-BENZ B-CLASS 2012 Owner's Manual

Display messages Possible causes/consequences and
M SolutionsLane Keeping
Assist Inoperative Lane Keeping Assist is faulty.
X
Visit a qualified specialist workshop. Blind Spot Assist
Currently
Unavailable See
Operator's
ManualBlind Spot
Assist Currently
Unavailable See
Operator's Manual Blind Spot Assist is temporarily inoperative. Possible causes are:
R
the sensors are dirty.
R 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.
When the causes stated above no longer apply, the display
message disappears.
Blind Spot Assist is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 149).
X Clean the sensors ( Y page 275).
X Restart the engine. Blind Spot Assist
Inoperative Blind Spot Assist is defective.
The yellow
9 indicator lamps also light up in the exterior
mirrors.
X Visit a qualified specialist workshop. Park Assist
Canceled The driver's door is open and the driver's seat belt has not been
fastened.
X
Repeat the parking process with the seat belt fastened and the
driver's door closed. You have inadvertently touched the multifunction steering wheel
while steering intervention was active.
X
While steering intervention is active, make sure that the
multifunction steering wheel is not touched unintentionally. The vehicle has started to skid and ESP
®
has intervened.
X Use Active Parking Assist again later (Y page 172).216
Display messagesOn-board computer and displays
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Display messages Possible causes/consequences and
M SolutionsPark Assist
Inoperative You have just carried out a large number of turning or parking
maneuvers.
Active Parking Assist will become available again after
approximately ten minutes (
Y page 172).
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Switch off and restart the engine.
If the display message continues to be displayed:
X Visit a qualified specialist workshop. PARKTRONIC is defective.
X
Visit a qualified specialist workshop. DISTRONIC PLUS Off DISTRONIC PLUS has been deactivated (
Y page 159). If it was
deactivated automatically, a warning tone also sounds. DISTRONIC PLUS Now
Available DISTRONIC PLUS is operational again after having been
temporarily
unavailable. You
can now reactivate DISTRONIC PLUS
(Y page 159). DISTRONIC PLUS
Currently
Unavailable See
Operator's Manual DISTRONIC PLUS is temporarily inoperative. Possible causes are:
R
function is impaired due to heavy rain or snow.
R the sensors in the radiator trim are dirty
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 system is outside the operating temperature range.
R the on-board voltage is too low.
A warning tone also sounds.
When the causes stated above no longer apply, the display
message disappears.
DISTRONIC is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 149).
X Clean the sensors in the radiator trim (Y page 275).
X Restart the engine. Display messages
217
On-board computer and displays Z
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Tires
Display messages Possible causes/consequences and
M SolutionsCheck
Tire Pressure Soon The tire pressure loss warning system has detected a significant
loss in pressure.
A warning tone also sounds.
G WARNING
With tire pressures which are too low, there is a risk of the
following hazards:
R they may burst, especially as the load and vehicle speed
increase.
R they may wear
excessively and/or unevenly, which may greatly
impair tire traction.
R the driving characteristics, as well as steering and braking, may
be greatly impaired.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
maneuvers. Pay attention

to the traffic conditions as you do so.
X Secure the vehicle against rolling away ( Y page 149).
X If there is a flat tire, inspect the tires ( Y page 281).
X Check the tire pressures and, if necessary, correct the tire
pressure.
X Restart the tire pressure loss warning system when the tire
pressure is correct (Y page 305). Check Tire Pressure
Then Restart Run
Flat Indicator The tire pressure loss warning system generated a display
message and has not been restarted since.
X
Set the correct tire pressure in all four tires.
X Restart the tire pressure loss warning system ( Y page 305).Run Flat Indicator
Inoperative The tire pressure loss warning system is faulty.
X
Visit a qualified specialist workshop. Display messages
219
On-board computer and displays Z
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Safety systems
Problem Possible causes/consequences and
M Solutions$ (USA only)
J (Canada only)
The red brake system
warning
lamp comes
on
while the engine is
running. A warning tone
also sounds. There is not enough brake fluid in the brake fluid reservoir.
G WARNING
The braking effect may be impaired.
There is a risk of an accident.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road

and traffic conditions. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away ( Y page 149).
X Do not add brake fluid. Adding more will not remedy the
malfunction.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. !
The yellow
ABS

warning
lamp is lit while the
engine is running. ABS (Anti-lock Braking System) is deactivated due to a
malfunction. BAS (Brake Assist), COLLISION PREVENTION
ASSIST, ESP
®
(Electronic Stability Program), the HOLD function
and hill start assist are therefore also deactivated, for example.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
The steerability and braking characteristics may be severely
affected. The braking distance in an emergency braking situation
can increase.
If ESP ®
is not

operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop.
If the ABS control unit is faulty, there is also a possibility that other
systems, such as the navigation system or the automatic
transmission, will not be available. Warning and indicator lamps in the instrument cluster
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On-board computer and displays Z
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Problem Possible causes/consequences and
M Solutions?
The red coolant
warning lamp
comes
on
while the engine is
running. The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator
may be blocked or the electric engine radiator fan may be
malfunctioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X
Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 149).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and add coolant (Y page 269). Observe
the warning notes.
X If you need to add coolant more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the coolant temperature is
under

248 ‡
(120 †). Otherwise, the engine could be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic. ?
The red coolant
warning lamp
comes

on
while the engine is
running. A warning tone
also sounds. The coolant temperature has exceeded 248 ‡ (120 †). The
airflow
to the
engine radiator may be blocked or the coolant level
may be too low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive
when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Vapor from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 149).232
Warning and indicator lamps in the instrument cluster
On-board computer and displays
ProCarManuals.com

X
To raise: using handle :, lift up cargo
compartment floor ; in the direction of
arrow = and pull it upwards.
X Lower cargo compartment floor ; again.
To do
this,
push the trunk floor away so that
it engages in the guide on the upper level.
Cargo compartment floor ; engages in
the upper position.
i Carry out this step using both hands.
X To lower: raise cargo compartment
floor ; slightly
using

handle : and pull it
towards you.
X Lower cargo compartment floor ; again
slowly. Whilst doing so, press the trunk
floor into the lower level.
Cargo compartment floor ; engages in
the lower position. Roof carrier
Important safety notes G
WARNING
When you load the roof, the center of gravity
of the vehicle rises and the driving
characteristics change. If you exceed the
maximum roof load, the driving
characteristics, as well as steering and
braking, will be greatly impaired. There is a
risk of an accident.
Never exceed the maximum roof load and
adjust your driving style.
! Mercedes-Benz recommends that you
only use roof

carriers that have been tested
and approved for Mercedes-Benz vehicles.
This helps to prevent damage to the
vehicle.
Position the load on the roof rack in such a
way that the vehicle will not sustain
damage even when it is in motion.
Ensure that, depending on the vehicle's
equipment, you can raise the panorama
roof with power tilt/sliding panel fully and open the tailgate fully when the roof carrier
is installed.
The maximum roof load is 165 lbs((75 kg).
An incorrectly secured roof carrier or roof
load may

become detached from the vehicle.
You must therefore ensure that you observe
the roof carrier manufacturer's installation
instructions.
Attaching the roof carrier X
Open covers : carefully in
the direction of
the arrow.
X Fold covers : upwards.
X Only secure the roof carrier to the
anchorage points under covers :.
X Observe the manufacturer's installation
instructions. Features
Cup holder
Important safety notes G
WARNING
The cup holder cannot hold a container secure
whilst traveling. If

you use a cup holder whilst
traveling, the container may be flung around
and liquid may be spilled. The vehicle
occupants may come into contact with the
liquid and if it is hot, they may be scalded. You
may be distracted from the traffic conditions
and you could lose control of the vehicle.
There is a risk of an accident and injury. Features
247
Stowage and features
ZProCarManuals.com

Emergency call
Important safety notes
!
You must have a license agreement to
activate the mbrace service. Make sure
that your system
is activated and ready for
use. To register, press the ï MB Info call
button. If any of the steps mentioned are
not carried out, the system may not be
activated.
If you have questions about the activation,
contact one of the following telephone
hotlines:
R USA: Mercedes-Benz Customer
Assistance Center at
1-800-FOR-MERCedes
(1-800-367-6372) or 1-866-990-9007
R Canada: Customer Service at
1-888-923-8367
General notes
An emergency call is dialed automatically if
an air bag or Emergency Tensioning Device is
triggered.
i You cannot end an automatically
triggered emergency call yourself.
An emergency call can also be initiated
manually.
As soon as the emergency call has been
initiated, the indicator lamp in the SOS button
flashes. The Connecting Call message
appears in the multifunction display.
The audio output is muted.
Once the connection has been made, the
Call Connected message appears in the
multifunction display.
All important information on the emergency
is transmitted, for example:
R Current location of the vehicle (as
determined by the GPS system)
R Vehicle identification number
R Information on the severity of the accident
Shortly after the emergency call has been
initiated, a voice connection is automatically
established between the Mercedes-Benz Customer Assistance Center and the vehicle
occupants.
R
If the vehicle occupants respond, the
Mercedes-Benz Customer Assistance
Center attempts to get more information
on the emergency.
R If there is no response from the vehicle
occupants, an ambulance is immediately
sent to the vehicle.
The mbrace system has not been able to
initiate an emergency call if no voice
connection to the

Response Center has been
established. This can occur, for example, if
the relevant mobile phone network is not
available. The indicator lamp in the SOS
button flashes continuously.
The Call Failed message appears in the
multifunction display and must be confirmed.
In this case, seek assistance by other means.
Making an emergency call G
WARNING
It can be dangerous to remain in the vehicle,
even if you

have pressed the SOS button in an
emergency if:
R you see smoke inside or outside of the
vehicle, e.g. if there is a fire after an
accident
R the vehicle is on a dangerous section of
road
R the vehicle is not visible or cannot easily be
seen by other road users, particularly when
dark or in poor visibility conditions
There is a risk of an accident and injury.
Leave the vehicle immediately in this or
similar situations as soon as it is safe to do
so. Move to a safe location along with other
vehicle occupants. In such situations, secure
the vehicle in accordance with national
regulations, e. g. with a warning triangle. Features
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Stowage and features Z
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Special service requirements
The specified
maintenance
interval takes only
the normal operation of the vehicle into
account. Under arduous operating conditions
or increased load on the vehicle,
maintenance work must be carried out more
frequently, for example:
R regular city driving with frequent
intermediate stops
R if the vehicle is primarily used to travel
short distances
R use in mountainous terrain or on poor road
surfaces
R if the engine is often left idling for long
periods
Under these or similar conditions, have, for
example, the air filter, engine oil and oil filter
replaced or changed more frequently. Under
arduous operating conditions, the tires must
be checked more often. Further information
can be obtained at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
Center.
Driving abroad
An extensive Mercedes-Benz Service network
is also available in other countries. You can
obtain further information from any
authorized Mercedes-Benz Center. Care
General notes
H
Environmental note
Dispose of empty packaging and cleaning
cloths in an environmentally responsible
manner.
! For cleaning your vehicle, do not use any
of the following:
R dry, rough or hard cloths
R abrasive cleaning agents
R solvents
R cleaning agents containing solvents Do not scrub.
Do not touch the surfaces or protective
films with hard objects, e.g. a ring or ice
scraper. You could otherwise scratch or
damage the surfaces and protective film.
! Do not park the vehicle for an extended
period straight after
cleaning it, particularly
after having cleaned the wheels with wheel
cleaner. Wheel cleaners could cause
increased corrosion of the brake discs and
brake pads/linings. For this reason, you
should drive for a few minutes after
cleaning. Braking heats the brake discs and
the brake pads/linings, thus drying them.
The vehicle can then be parked.
Regular care of your vehicle is a condition for
retaining the quality in the long term.
Use care products and cleaning agents
recommended and approved by Mercedes-
Benz. Exterior care
Automatic car wash G
WARNING
Braking efficiency is reduced after washing
the vehicle. There is a risk of an accident.
After the vehicle has been washed, brake
carefully while paying attention to the traffic
conditions until full

braking power is restored.
! If DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes
automatically in certain situations. To
prevent damage to the vehicle, deactivate
DISTRONIC PLUS and the HOLD function in
the following or other similar situations:
R when towing the vehicle
R in the car wash
! Never clean your vehicle in a Touchless
Automatic Car Wash as these use special
cleaning agents. These cleaning agents can
damage the paintwork or plastic parts. Care
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Maintenance and care Z
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Cleaning the wheels
!
Do not use
acidic wheel cleaning products
to remove brake dust. This could damage
wheel bolts and brake components.
! Do not park the vehicle for an extended
period straight after cleaning it, particularly
after having cleaned the wheels with wheel
cleaner. Wheel cleaners could cause
increased corrosion of the brake discs and
brake pads/linings. For this reason, you
should drive for a few minutes after
cleaning. Braking heats the brake discs and
the brake pads/linings, thus drying them.
The vehicle can then be parked.
Cleaning the paintwork !
Do not affix:
R stickers
R films
R magnetic plates or similar items
to painted surfaces. You could otherwise
damage the paintwork.
X Remove dirt immediately, where possible,
while avoiding rubbing too hard.
X Soak insect remains with insect remover
and rinse off the treated areas afterwards.
X Soak bird droppings with water and rinse
off the treated areas afterwards.
X Remove coolant, brake fluid, tree resin,
oils, fuels and greases by rubbing gently
with a cloth soaked in petroleum ether or
lighter fluid.
X Use tar remover to remove tar stains.
X Use silicone remover to remove wax.
X Use a suitable touch-up stick, e.g. MB
Touch-Up Stick, to repair slight damage to
the paintwork quickly and provisionally.
The following cannot always be completely
repaired:
R scratches
R corrosive deposits R
areas affected by corrosion
R damage caused by inadequate care
In such cases, visit a qualified specialist
workshop.
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 the dirt has penetrated the paint surface or
if the paintwork has become dull, then the
paintwork should be cleaned. For cleaning,
please use the paint cleaner recommend and
approved by Mercedes Benz.
Do not use these care products in the sun or
on the hood while the hood is hot.
Matte finish care !
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 carried out
at a qualified specialist workshop.
! Do not use wash programs with a hot wax
treatment under any circumstances.
Observe these notes if your vehicle has a
clear matte finish. This will help you to avoid
damage to the paintwork due to incorrect
treatment. Care
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Maintenance and care Z
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X
Open the tailgate.
X Lift the cargo compartment floor up
(Y page 246).
i Towing eye ; is located under tire
inflation compressor :.
Vehicles with a tire-change tool kit X
Open the tailgate.
X Lift the cargo compartment floor up
(Y page 246).
X Remove the tire-change tool kit.
The tire-change tool kit contains:
R Jack
R Lug wrench
R One pair of gloves
R Folding wheel chock Flat tire
Preparing the vehicle
Your vehicle may be equipped with:
R MOExtended tires (tires with run-flat
properties) ( Y page 281)
Vehicle preparation is not necessary on
vehicles with MOExtended tires.
R a TIREFIT kit (Y page 280)
Information on changing/mounting a wheel
(Y page 319).
X Stop the vehicle on solid, non-slippery and
level ground, as far away as possible from
traffic.
X Switch on the hazard warning lamps.
X Secure the vehicle against rolling away
(Y page 149).
X If possible, bring the front wheels into the
straight-ahead position.
X Switch off the engine.
X Remove the SmartKey from the ignition
lock. X
All occupants must get out of the vehicle.
Make sure that
they are not endangered as
they do so.
X Make 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.
X Get out of the vehicle. Pay attention to
traffic conditions when doing so.
X Close the driver's door.
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 a
qualified specialist workshop. MOExtended tires (tires with run-flat
properties)
General notes With MOExtended tires (tires with run flat
characteristics), you can continue to drive
your vehicle even if there is a total loss of
pressure in one or more tires. The affected
tire must
not

show any clearly visible damage.
You can recognize MOExtended tires by the
MOExtended marking which appears on the
sidewall of the tire. You will find this marking
next to the tire size designation, the load-
bearing capacity and the speed index
(Y page 313).
MOExtended tires may only be used in
conjunction with an active tire pressure loss
warning system.
If the pressure loss warning message
appears in the multifunction display:
R Observe the instructions in the display
messages ( Y page 219).
R Check the tire for damage.
R If driving on, observe the following notes. Flat tire
281
Breakdown assistance
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