MERCEDES-BENZ B-CLASS 2012 Owners Manual

Problems with the engine
Problem Possible causes/consequences and
M SolutionsThe engine does not
start. The HOLD function or DISTRONIC PLUS is activated.
X
Deactivate the HOLD function (Y page 167) or DISTRONIC
PLUS (Y page 159).
X Try to start the engine again. The engine does not
start.
The starter
motor
can be heard. R
There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.
X Turn the SmartKey back to position 0
in the

ignition lock before
attempting to start the engine again.
X Try to start the engine again (Y page 135). Avoid excessively
long and frequent

attempts to start the engine as these will drain
the battery.
If the engine does not start after several attempts:
X Consult a qualified specialist workshop. The engine does not
start. You cannot hear
the starter motor. The on-board voltage is too low because the battery is too weak
or discharged.
X
Jump-start the vehicle (Y page 289).
If the engine does not start despite attempts to jump-start it:
X Consult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center. The starter motor was exposed to a thermal load that was too high.
X
Allow the starter motor to cool down for approximately two
minutes.
X Try to start the engine again.
If the engine still does not start:
X Consult a qualified specialist workshop. Driving
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Problem Possible causes/consequences and
M SolutionsThe engine is not
running smoothly and
is misfiring. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
X
Only depress the accelerator pedal slightly.
X Have the cause rectified immediately at a qualified specialist
workshop.
Otherwise, non-combusted fuel may get into the catalytic
converter and damage it. The coolant
temperature display is
showing more than
248 ‡
(120 †). The
coolant warning lamp
may also be lit and a
warning tone may
sound. The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
X
Stop as soon as possible and allow the engine and the coolant
to cool down.
X Check the coolant level (Y page 269). Observe the warning
notes as you do so and add coolant if necessary. Automatic transmission
Important safety notes
G
WARNING
If the engine speed is above the idling speed
and you engage transmission position D or
R, the vehicle
could pull away suddenly. There
is a risk of an accident.
When engaging transmission position D or R,
always firmly depress the brake pedal and do
not simultaneously accelerate. G
WARNING
The automatic transmission switches to
neutral position N when you switch off the
engine. The vehicle may roll away. There is a
risk of an accident.
After switching off the engine, always switch
to parking position P. Prevent the parked
vehicle from rolling away by applying the
parking brake. DIRECT SELECT lever
Overview of transmission positions The DIRECT SELECT lever is on the right of the
steering column.
j
Park position with parking lock
k Reverse gear
i Neutral
h Drive
i The DIRECT SELECT lever always returns
to its original position. The current
transmission position
P, R

, N or D appears
in the transmission position display
(Y page 141) in the multifunction display. 140
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Transmission position and drive
program display
The current transmission position and drive
program appear in the multifunction display.
:
Transmission position display
; Drive program display
i The arrows in the transmission position
display show how and into which
transmission positions you can change
using the DIRECT SELECT lever.
! If the
transmission
position display in the
multifunction display is not working, you
should pull away carefully to check whether
the desired transmission position is
engaged. Ideally, you should select
transmission position D and drive program
E or S.
Engaging park position P X
Push the DIRECT SELECT lever in the
direction of arrow P.
Transmission position display P

is shown in
the multifunction display.
i When you engage park position P, make
sure that the

transmission position display
shows P in the multifunction display.
i You can only engage park position P when
the vehicle is stationary.
i The automatic transmission shifts into
park position P automatically:
R if you open the driver's door while the
vehicle is stationary in transmission
position D or R
R if you open the door while traveling at
very low speeds in transmission position
D or R In addition, a warning tone sounds and a
display message is shown.
i Depressing the brake and pushing the
DIRECT SELECT lever up or down
disengages the parking lock. The
transmission is in N neutral.
At transmission fluid temperatures below
Ò4 ‡ (Ò 20

†), you can only shift out of park
position P into another transmission
position when the engine is running.
In order to shift from park position P
directly into R or D:
R depress the brake pedal and
R push the DIRECT SELECT lever up or
down past the first point of resistance
! If the engine speed is too high or the
vehicle is moving, do not shift the
automatic transmission directly from D to
R, from R to D or directly to P. The
automatic transmission could otherwise be
damaged.
Engaging reverse gear R !
Only shift the automatic transmission to
R when the vehicle is stationary.
i The ECO start/stop function is not
available when reverse gear is engaged.
Further information on

the ECO start/stop
function ( Y page 136).
X When the vehicle is stationary, depress the
brake pedal.
X Push the DIRECT SELECT lever up past the
first point of resistance.
Shifting to neutral N X
When the vehicle is stationary, depress the
brake pedal.
X Push the DIRECT SELECT lever up or down
to the first point of resistance.
If the engine has been switched off, the
automatic transmission automatically shifts
to N. Automatic transmission
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Remaining in neutral N
If the automatic transmission is to remain in
neutral N, e.g. for washing the vehicle in car
washes with
a
towing device, please observe
the following instructions: G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shift the automatic transmission out of
parking position P.
R starting the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you

and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
R Make sure that the ignition is switched on.
R When the vehicle is stationary, depress the
brake pedal and keep it depressed.
R Shift to neutral N.
R Release the brake pedal.
R If the electric parking brake is engaged,
release it.
R Switch off the ignition and leave the
SmartKey in the ignition lock.
Engaging drive position D X
When the vehicle is stationary, depress the
brake pedal.
X Push the DIRECT SELECT lever down past
the first point of resistance. Transmission positions
B
Park position
Do not shift the transmission into
position P unless the vehicle is
stationary (
Y page 149). The
parking lock should

not be used as
a brake when parking. Always
apply the electronic parking brake
in addition to the parking lock in
order to secure the vehicle.
If the vehicle electronics are
malfunctioning, the transmission
may be locked in position P.
Have the vehicle electronics
checked immediately at a qualified
specialist workshop. C
Reverse gear
Only shift the transmission to
R
when the vehicle is stationary. A
Neutral
No power is transmitted from the
engine to the drive wheels.
Releasing the
brakes

will allow you
to move the vehicle freely, e.g. to
push it or tow it.
If ESP ®
is deactivated or faulty:
only shift the transmission to
position N if the vehicle is in danger
of skidding, e.g. on icy roads.
When you switch off the engine, the
automatic transmission
automatically shifts into neutral N. 7
Drive
The automatic transmission
changes gear automatically. All
forward gears are available.142
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Changing gear
The automatic transmission shifts to the
individual gears automatically when it is in
transmission position D. This automatic
gearshifting behavior is determined by:
R the selected drive program ( Y page 143)
R the position of the accelerator pedal
R the road speed Driving tips
Holding the vehicle stationary on uphill
gradients G
WARNING
If the clutch overheats, the electronic
management system is automatically
deactivated. This interrupts the power
transmission. The vehicle may, for example,
roll backwards on

gradients. There is a risk of
an accident.
Never hold the vehicle stationary on uphill
gradients by depressing the accelerator.
The clutch may overheat if you hold the
vehicle stationary on uphill gradients by
depressing the accelerator pedal. If the clutch
overheats, a warning tone sounds. The Stop
Vehicle Shift to P Leave Engine
Running display message appears in the
multifunction display. You will only be able to
continue your journey once the clutch has
cooled down and the display message in the
multifunction display has disappeared.
Never hold the vehicle stationary on uphill
gradients by depressing the accelerator.
Instead, only ever hold the vehicle stationary
on uphill gradients by:
R depressing the brake pedal
R activating the HOLD function
R engaging the electric parking brake Kickdown Use kickdown for maximum acceleration:
X
Depress the accelerator pedal beyond the
pressure point.
The automatic transmission shifts to a
lower gear depending

on the engine speed.
X Ease off the accelerator pedal once the
desired speed is reached.
The automatic transmission

shifts back up.
Rocking the vehicle free Shifting the transmission repeatedly between
gears
D and R may help to free the vehicle if
it has become stuck in slush or snow. The
vehicle's engine management system limits
the speed to a maximum of 5 mph (9 km/h)
when shifting back and forth. To shift back
and forth between transmission positions D
and R, move the selector lever up and down
beyond the pressure point. Program selector button
General notes The program selector button allows you to
choose between drive programs with
different driving characteristics.
Example: program selector button Automatic transmission
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E Economy Comfortable, economical
driving
S Sport Sporty driving style
M Manual Manual gear shifting
Only change from automatic drive program
E or S to manual drive program
M when the
vehicle is stationary.
X Press program selector button :
repeatedly until the letter for the desired
gearshift program appears in the
multifunction display.
i The automatic transmission shifts to
automatic drive program E each time the
engine is started.
i For further information on the automatic
drive program, see ( Y page 144). Steering wheel paddle shifters
:
Left steering wheel paddle shifter (shifts
down)
; Right steering wheel paddle shifter (shifts
up)
In drive program M, you can change gear
yourself using the steering wheel paddle
shifters.
If you pull the left or right steering wheel
paddle shifter when in automatic drive
program E or S, the automatic transmission
shifts into drive
program M for a limited time.
Depending on which paddle shifter is pulled, the automatic transmission immediately
shifts into the next gear down or up.
i
You can only change gear with the
steering wheel paddle shifters when the
transmission is in position D.
i For further information on the manual
drive program, see ( Y page 144). Automatic drive program
Drive program E is characterized by the
following:
R comfort-oriented engine settings
R optimal fuel consumption resulting from
the automatic transmission shifting up
sooner
R the vehicle pulling away more gently in
forward and reverse gears, unless the
accelerator pedal is depressed fully
R increased sensitivity. This

improves driving
stability on slippery road surfaces, for
example
R the automatic transmission shifting up
sooner. This results in the vehicle being
driven at lower engine speeds and the
wheels being less likely to spin
Drive program S is characterized by the
following:
R sporty engine settings
R the automatic transmission shifting up
later
R the fuel consumption possibly being higher
as a result of the later automatic
transmission shift points Manual drive program
Introduction In manual drive program
M, you can change
gear yourself by using the steering wheel
paddle shifters. For this, the transmission
must be in position D. The gear currently 144
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selected and engaged is shown in the
multifunction display.
Manual drive program
M differs from drive
programs E and S
with regard to spontaneity,
responsiveness and smoothness of gear
changes. Gear Driving situations
=
You can use the engine's braking
effect
5
To use the braking effect of the
engine on downhill gradients and
for driving:
R
on steep mountain roads
R in mountainous terrain
R in arduous conditions 4
To use the braking effect of the
engine on
extremely

steep downhill
gradients and on long downhill
stretches Switching on the manual drive program
Activating permanently
X
Press the program selector button
(Y page 143)

repeatedly until M appears in
the multifunction display.
Manual drive program M remains active
until drive program E or S is engaged.
Activating temporarily
X Pull the right or left steering wheel paddle
shifter (Y page 144).
M is shown in the multifunction display.
Manual drive program M is temporarily
active. Depending on which paddle shifter
is pulled, the automatic transmission
immediately shifts into

the next gear down
or up.
i When manual drive program M is
activated via the steering wheel paddle
shifters, the temporarily active manual
drive program M will be deactivated
automatically after a limited time, if the
driving situation permits. In this case, the automatic transmission shifts into the
automatic drive program that was last
engaged, i.e.
E or S. When driving on
downhill gradients, the temporarily active
manual drive program M will only be
deactivated if the accelerator pedal is
depressed while the vehicle is rolling
downhill.
Upshifting X
Pull the right-hand steering wheel paddle
shifter (Y page 144).
The automatic transmission

shifts up to the
next gear.
X Shift up a gear when the ^ upshift symbol
appears in the display instead of M.
i To prevent engine damage the automatic
transmission shifts up automatically:
R if the maximum engine speed on the
currently engaged gear is reached and
R you continue to accelerate.
Downshifting X
Pull the left-hand steering wheel paddle
shifter (Y page 144).
The automatic transmission

shifts down to
the next gear.
i If you slow down or stop without shifting
down, the automatic transmission
automatically shifts down.
i For maximum acceleration, pull the left-
hand steering wheel

paddle shifter until the
transmission selects the optimum gear for
the current speed.
i If the engine exceeds the maximum
engine speed when shifting down, the
automatic transmission protects against
engine damage by not shifting down. Automatic transmission
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Kickdown
You can also use kickdown for maximum
acceleration in manual drive program
M.
X Depress the accelerator pedal beyond the
pressure point.
The transmission shifts to a lower gear
depending on the engine speed.
X Shift back up once the desired speed is
reached.
i During kickdown, you
cannot change gear
using the steering wheel paddle shifters.
i If you apply full throttle, the automatic
transmission shifts up to the next gear
when the maximum engine speed is
reached. This prevents the engine from
overrevving.
Switching off the manual drive program X
Press the program selector button
(Y page 143) repeatedly until E or S
appears in the multifunction display.
Deactivating the temporary manual drive
program
X Pull and hold the right-hand steering wheel
paddle shifter until the automatic
transmission shifts into the last active
automatic drive program: E or S.
i If manual drive

program M is deactivated,
the automatic transmission in automatic
drive program E or S may shift from the
current gear into a higher or lower gear.
This is dependent on the position of the
accelerator pedal, speed and load. 146
Automatic transmission
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Problems with the transmission
Problem Possible causes/consequences and
M SolutionsThe transmission has
problems shifting gear. The transmission is losing oil.
X
Have the transmission checked at a qualified specialist
workshop immediately. The acceleration ability
is deteriorating.
The transmission no
longer shifts into all of
the gears.
Reverse gear can no
longer be engaged. The transmission is in emergency mode.
X
Stop the vehicle.
X Shift the transmission to position P.
X Switch off the engine.
X Wait at least 10 seconds before restarting the engine.
X Shift the transmission to position D.
X Have the transmission checked at a qualified specialist
workshop immediately. Refueling
Important safety notes
G
WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and
explosion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable,
the auxiliary heating before
refueling. G
WARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make

sure that fuel does not come
into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children.
If you or others come into contact with fuel,
observe the following:
R Wash away fuel from skin immediately
using soap and water.
R If fuel comes into contact with your eyes,
immediately rinse them thoroughly with clean water. Seek medical assistance
without delay.
R If fuel is swallowed, seek medical
assistance without delay. Do not induce
vomiting.
R Immediately change out of clothing which
has come into contact with fuel. G
WARNING
Electrostatic buildup can create sparks and
ignite fuel vapors. There is a risk of fire and
explosion.
Always touch the

vehicle body before opening
the fuel filler flap or touching the fuel pump
nozzle. Any existing electrostatic buildup is
thereby discharged.
! Do not use diesel to refuel vehicles with a
gasoline engine. Do not switch on the
ignition if you accidentally refuel with the
wrong fuel. Otherwise, the fuel will enter
the fuel system. Even small amounts of the
wrong fuel could result in damage to the
fuel system and the engine. The repair
costs are high. Notify a qualified specialist
workshop and have the fuel tank and fuel
lines drained completely. Refueling
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!
Overfilling the fuel
tank could damage the
fuel system.
! Take care not to spill any fuel on painted
surfaces. You could otherwise damage the
paintwork.
! Use a filter when refueling from a fuel can.
Otherwise, the fuel lines and/or injection
system could be blocked by particles from
the fuel can.
Do not get into the vehicle again during the
refueling process. Otherwise, electrostatic
charge could build up again.
If you overfill the fuel tank, fuel could spray
out when the fuel pump nozzle is removed.
For further information on fuel and fuel quality
(Y page 330). Refueling
Opening/closing the fuel filler flap :
To open the fuel filler flap
; Tire pressure table
= To insert the fuel filler cap
? Fuel type to be used
The fuel filler flap is unlocked or locked
automatically when you open or close the
vehicle with the SmartKey.
The position of the fuel filler cap is displayed
æ in
the

instrument cluster. The arrow on
the filling pump indicates the side of the
vehicle. Opening X
Switch the engine off.
X Remove the SmartKey from the ignition
lock.
X Press the fuel filler flap in the direction of
arrow :.
The fuel filler flap swings up.
X Turn the fuel filler flap counter-clockwise
and remove it.
X Insert the fuel filler cap into holder on the
inside of fuel filler flap =.
X Completely insert the filler neck of the fuel
pump nozzle into the tank, hook in place
and refuel.
X Only fill the tank until the pump nozzle
switches off.
i Do not add any more fuel after the pump
stops filling for the first time. Otherwise,
fuel may leak out.
Closing X
Replace the cap on the filler neck and turn
clockwise until it engages audibly.
X Close the fuel filler flap.
i Close the fuel

filler flap before locking the
vehicle.
i If you are driving with the fuel filler cap
open, the 8 reserve fuel warning lamp
flashes. A message appears in the
multifunction display ( Y page 214).
In addition, the ; Check Engine warning
lamp may light up ( Y page 231).
For further information on warning and
indicator lamps in the instrument cluster,
see ( Y page 231).148
Refueling
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