2012 MERCEDES-BENZ B-CLASS warning light

Warning and indicator lamps in the instrument cluster
Seat belts
Problem Possible causes/consequences and
M Solutionsü
After starting the
engine, the red seat
belt warning
lamp
lights
up for six seconds. The seat belt warning lamp reminds the driver and front passenger
to fasten their seat belts.
X
Fasten your seat belt ( Y page 45).ü
After starting the
engine, the red seat
belt warning
lamp

lights
up. In addition, a
warning tone sounds
for up to six seconds. The driver's seat belt is not fastened.
X
Fasten your seat belt ( Y page 45).
The warning tone ceases. ü
The red seat belt
warning lamp lights up
after the engine starts,
as soon as the driver's
or the front-passenger
door is closed.
The driver or front passenger has not fastened their seat belt.
X
Fasten your seat belt ( Y page 45).
The warning lamp goes out. There are objects on the front-passenger seat.
X
Remove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out. ü
The red seat belt
warning lamp flashes
and an intermittent
audible warning
sounds.
The driver or front passenger has not fastened their seat belt. In
addition,
you are

driving faster than 15 mph (25 km/h) or you have
briefly driven faster than 15 mph (25 km/h).
X Fasten your seat belt ( Y page 45).
The warning lamp goes out and the intermittent warning tone
ceases. There are objects on the front-passenger seat. In addition, you are
driving faster than 15 mph (25 km/h
) or you have briefly driven
faster than 15 mph (25 km/h ).
X Remove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out and the intermittent warning tone
ceases.224
Warning and indicator lamps in the instrument cluster
On-board computer and displays
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Problem Possible causes/consequences and
M Solutions!
The yellow
ABS
warning
lamp is lit while the
engine is running. ABS is temporarily unavailable. BAS, COLLISION PREVENTION
ASSIST,
ESP®
, EBD
(electronic brake force distribution), the HOLD
function and hill start assist are therefore also deactivated, for
example.
Possible causes are:
R Self-diagnosis is not yet complete.
R The on-board voltage may be insufficient.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear 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 a risk of an accident.
X Carefully drive on a suitable stretch of road, making slight
steering movements at a speed above 12 mph (20 km/h).
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop.226
Warning and indicator lamps in the instrument cluster
On-board computer and displays
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Problem Possible causes/consequences and
M Solutions֌
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
, BAS, the HOLD function and hill start assist are temporarily
unavailable.
COLLISION PREVENTION ASSIST may also have failed.
ATTENTION ASSIST is deactivated.
Self-diagnosis is not yet complete.
G WARNING
The brake
system continues to function normally, but without the
functions listed above.
The braking distance in an emergency braking situation can thus
increase.
If ESP ®
is not

operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Carefully drive on a suitable stretch of road, making slight
steering movements at a speed above 12 mph (20 km/h).
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
229
On-board computer and displays Z
ProCarManuals.com

Problem Possible causes/consequences and
M SolutionsF (USA only)
! (Canada only)
The red indicator lamp
for the electric parking
brake flashes or lights
up and/or the yellow
warning lamp for the
electric parking brake
lights up. X
Observe the additional display messages in the multifunction
display. 6
The red SRS warning
lamp is lit while the
engine is running.
There is a malfunction in the SRS (Supplemental Restraint
System).
G WARNING
The air bags or Emergency Tensioning Devices may either be
triggered unintentionally or, in the event of an accident, may not
be triggered.
There is an increased risk of injury.
X Drive on carefully.
X Have SRS checked at a qualified specialist workshop
immediately.
For further information about SRS, see (Y page 38). 230
Warning and indicator lamps in the instrument clusterOn-board computer and displays
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Engine
Problem Possible causes/consequences and
M Solutions;
The yellow Check
Engine warning lamp
lights up while the
engine is running.
There may be a malfunction, for example:
R
in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system
R in the fuel system
The emission limit values may be exceeded and the engine may
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states, you must immediately visit a qualified
specialist workshop as
soon as the yellow Check Engine warning
lamp lights up. This depends on the locally applicable legal
requirements. If in doubt, check whether such legal regulations
apply in the state in which you are currently driving. æ
The yellow reserve fuel
warning lamp lights up
while the engine is
running.
The fuel level has dropped into the reserve range.
X
Refuel at the nearest gas station. æ
The yellow reserve fuel
warning lamp flashes
while the engine is
running.
The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.
X
Check that the fuel filler cap is correctly closed.
X If the fuel filler cap is not correctly closed:
close the

fuel filler
cap.
X If the fuel filler cap is closed: visit a qualified specialist
workshop. ?
The red coolant
warning lamp lights up
while the engine is
running and
the

coolant
temperature gage is at
the start of the scale. The temperature sensor for the coolant temperature gage is
defective.
The coolant
temperature
is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.
X Pull over and stop the vehicle safely and switch off the engine,
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 Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
231
On-board computer and displays Z
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Problem Possible causes/consequences and
M SolutionsX
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 At
coolant temperatures under 248 ‡ (120 †),
drive to the next
qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic. Driving systems
Problem Possible causes/consequences and
M Solutions·
The red distance
warning lamp lights up
while the vehicle is in
motion. A
warning

tone
also sounds. You are approaching a vehicle or a stationary obstacle in your line
of travel at too high a speed.
X
Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to
brake or take evasive action. Warning and indicator lamps in the instrument cluster
233
On-board computer and displays Z
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Stowage compartment in front of the
armrest (vehicles with automatic
transmission)
X
To open: press the marking on cover :.
i You can remove
the non-slip mat and the
insert for cleaning. When removing the
insert you will have to overcome some
slight resistance.
Stowage compartment under the armrest X
To open: on vehicles with moveable
armrests, make sure that the armrest is in
the rearmost position.
X Press button : and fold the armrest up.
i Depending on the vehicle's equipment, a
USB connection and

an AUX IN connection
or a Media Interface are installed in the
stowage compartment. A Media Interface
is a universal interface for mobile audio
equipment, e.g. for an iPod ®
or MP3 player
(see the separate COMAND Operating
Instructions). Stowage compartment under the driver's
seat and front-passenger seat G
WARNING
If you exceed the maximum load for the
stowage compartment, the cover may not be
able to restrain the items. Items may be
thrown out of the stowage compartment and
hit vehicle occupants.

There is a risk of injury,
particularly in the event of sudden braking or
a sudden change in direction.
Never exceed the maximum permissible load
for the stowage compartment. Stow and
secure heavy objects in the cargo
compartment.
The maximum permissible load of the
stowage compartment is 2.6 lbs (1.5 kg). X
To open: pull handle : up and fold
cover ; forwards.
Stowage space in the rear Stowage compartment in the rear center
console238
Stowage areas
Stowage and features
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Depending on the angle of the backrest,
therefore, the right and left rear seats can
be pushed
back
varying distances until the
backrest is resting against the cargo
compartment cover.
If the backrest comes into contact with
surrounding parts of the cargo
compartment paneling, reduce the angle of
the backrest.
Adjusting the seat fore-and-aft position
! When moving the rear seats back, make
sure there are no objects in the footwell or
behind the seats. The rear seats and/or the
objects could otherwise be damaged. X
Lift the left or right release handle and slide
the corresponding seat forwards or
backwards.
X Let go of the release handle again.
Make sure that

you hear the seat engage in
position. Securing cargo
Cargo tie-down rings Observe the following notes on securing
loads:
R
Observe the loading guidelines
(Y page 236).
R Secure the load using the cargo tie-down
rings.
R Distribute the load on the cargo tie-down
rings evenly. R
Do not use
elastic straps or nets to secure
a load, as these are only intended as an
anti-slip protection for light loads.
R Do not route tie-downs across sharp edges
or corners.
R Pad sharp edges for protection.
There are four cargo tie-down rings in the
cargo compartment. :
Cargo tie-down rings
Bag hook G
WARNING
The bag hooks cannot restrain heavy objects
or items of luggage. Objects or items of
luggage could be

flung around and thereby hit
vehicle occupants when braking or abruptly
changing directions. There is a risk of injury.
Only hang light objects on the bag hooks.
Never hang hard, sharp-edged or fragile
objects on the bag hooks.
! The bag hook can bear a maximum load
of 6.6lbs (3kg) and should not be used to
secure a load.
There is one bag hook on either side of the
cargo compartment. Stowage areas
243
Stowage and features Z
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