ignition MERCEDES-BENZ B-CLASS 2012 Manual Online

Checking and adding other service
products
Checking coolant level G
WARNING
The engine cooling system is pressurized,
particularly when the engine is warm. When
opening the cap,
you could be scalded by hot
coolant spraying out. There is a risk of injury.
Let the engine cool down before opening the
cap. Wear eye and hand protection when
opening the cap. Open the cap slowly half a
turn to allow pressure to escape.
! The coolant may only be checked and
corrected when the engine is cool (coolant
temperature below 104 ‡ (40 †).
Checking the coolant when the coolant
temperature is above 104 ‡ (40 †) may
result in damage to the engine or to the
engine cooling system. Example
X
Park the vehicle on a level surface.
Only check the coolant level when the
vehicle is on

a level surface and the engine
has cooled down.
X Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X Check the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
104 ‡ (40 †).
X Turn the SmartKey to position
0 (

Y page 135) in the ignition lock. X
Slowly turn cap : half a turn counter-
clockwise to allow excess pressure to
escape.
X Turn cap : further counter-clockwise
and
remove it.
If the coolant is at the level of marker bar
= in the filler neck when cold, there is
enough coolant in coolant expansion
tank ;.
X If necessary, add coolant that has been
tested and approved by Mercedes-Benz.
X Replace cap : and turn

it clockwise as far
as it will go.
For further information on coolant, see
(Y page 333).
Adding washer fluid to the windshield
washer system/headlamp cleaning
system G
WARNING
Windshield washer concentrate is highly
flammable. If it comes into contact with hot
engine components or the exhaust system it
could ignite. There is a risk of fire and injury.
Make sure that no windshield washer
concentrate is spilled next to the filler neck. Example
X
To open: pull cap : upwards by the tab.
X Add the premixed washer fluid.
X To close:
press cap :
onto the filler neck
until it engages. Engine compartment
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Maintenance and care Z
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The washer fluid reservoir is used for both the
windshield washer
system
and the headlamp
cleaning system.
The recommended minimum amount when
topping up is 1 liter. If the water level drops
below this, a message appears in the
multifunction display prompting you to refill
the washer fluid ( Y page 223).
Further information on windshield washer
fluid/antifreeze ( Y page 334).Maintenance
ASSYST PLUS
Service messages The ASSYST PLUS service interval display
informs you of the next service due date.
Information on
the

type of service and service
intervals (see the separate Maintenance
Booklet).
You can obtain further information from an
authorized Mercedes-Benz Center or at
http://www.mbusa.com (USA only).
i The ASSYST PLUS service interval display
does not show any information on the
engine oil level. Observe the notes on the
engine oil level ( Y page 267).
The multifunction display shows a service
message for several seconds, e.g.:
R Next Service A in .. Days
R Service A Due
R Service A Exceeded by .. Days
Depending on the operating conditions of the
vehicle, the remaining time or distance until
the next service due date is displayed.
The letter A or B, possibly in connection with
a number or another letter, shows the type of
service. A stands for a minor service and B for
a major service.
You can obtain further information from an
authorized Mercedes-Benz Center.
The ASSYST PLUS service interval display
does not take into account any periods of time during which the battery is
disconnected.
Maintaining the time-dependent service
schedule:
X
Note down the service due date displayed
in the multifunction display before
disconnecting the battery.
or
X After reconnecting the battery, subtract
the battery
disconnection

periods from the
service date shown on the display.
Hiding a service message X
Press % or a.
Displaying service messages X
Switch on the ignition.
X Using = or ;, select the Serv.
menu.
X Press 9 or : to select the ASSYST
PLUS submenu and

press a to confirm.
The service due date appears in the
multifunction display.
Information about Service Resetting the ASSYST PLUS service
interval display
!
If the ASSYST PLUS service interval
display has been inadvertently reset, this
setting can be corrected at a qualified
specialist workshop.
Have service work

carried out as described
in the Maintenance Booklet. This may
otherwise lead to increased wear and
damage to the major assemblies or the
vehicle.
A qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center, will reset
the ASSYST PLUS service interval display
after the service work has been carried out.
You can also obtain further information on
maintenance work, for example. 270
Maintenance
Maintenance and care
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These notes also apply to light alloy wheels
with a clear matte finish.
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.
Cleaning the windows G
WARNING
You could become trapped by the windshield
wipers if they

start moving while cleaning the
windshield or wiper blades. There is a risk of
injury.
Always switch off the windshield wipers and
the ignition before cleaning the windshield or
wiper blades.
! Only fold the windshield wipers away from
the windshield when vertical. Otherwise,
you will damage the hood.
! Do not use dry cloths, abrasive products,
solvents or cleaning agents containing
solvents to clean the inside of the windows.
Do not touch the insides of the windows
with hard objects, e.g. an ice scraper or
ring. There is otherwise a risk of damaging
the windows.
! Clean the water drainage channels of the
windshield and the rear window at regular
intervals. Deposits such as leaves, petals
and pollen may under certain
circumstances prevent water from draining
away. This can lead to corrosion damage
and damage to electronic components.
X Clean the inside and outside of the
windows with a damp cloth and a cleaning
product that is recommended and
approved by Mercedes-Benz. Cleaning wiper blades G
WARNING
You could become trapped by the windshield
wipers if they

start moving while cleaning the
windshield or wiper blades. There is a risk of
injury.
Always switch off the windshield wipers and
the ignition before cleaning the windshield or
wiper blades.
! Only fold the windshield wipers away from
the windshield when vertical. Otherwise,
you will damage the hood.
! Do not pull the wiper blade. Otherwise,
the wiper blade could be damaged.
! Do not clean wiper blades too often and
do not rub them too hard. Otherwise, the
graphite coating could be damaged. This
could cause wiper noise.
X Fold the windshield wiper arms away from
the windshield.
X Carefully clean the wiper blades with a
damp cloth.
X Fold the windshield wiper arms back again
before switching on the ignition.
! Hold the wiper

arm securely when folding
back. The windshield could be damaged if
the wiper arm smacks against it suddenly.
Cleaning the exterior lighting !
Only use cleaning agents or cleaning
cloths which are suitable for plastic light
lenses. Unsuitable cleaning agents or
cleaning cloths could scratch or damage
the plastic light lenses.
X Clean the plastic lenses of the exterior
lighting using a wet sponge and a mild
cleaning agent, e.g. Mercedes-Benz car
shampoo or cleaning cloths.274
Care
Maintenance and care
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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
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If you come into contact with the tire sealant,
observe the following:
R
Rinse off the tire sealant from your skin
immediately with water.
R If the tire sealant comes into contact with
your eyes, immediately rinse them
thoroughly with clean water.
R If tire sealant is swallowed, immediately
rinse your mouth out thoroughly and drink
plenty of water. Do not induce vomiting,
and seek medical attention immediately.
R Immediately change out of clothing which
has come into contact with tire sealant.
R If an allergic
reaction occurs, seek medical
attention immediately.
Using the TIREFIT kit TIREFIT is a tire sealant.
You can use TIREFIT to seal punctures of up
to 0.16
in

(4 mm), particularly those in the tire
tread. You can use TIREFIT at outside
temperatures down to Ò4 ‡ (Ò20 †). TIREFIT sticker, 2-part
X
Do not remove any foreign objects which
have penetrated the tire, e.g. screws or
nails.
X Remove the tire sealant bottle, the
accompanying TIREFIT sticker and the tire
inflation compressor
from

the stowage well
underneath the cargo compartment floor
(Y page 280). X
Affix part : of the TIREFIT sticker within
the driver's field of vision.
X Affix part ; of
the
TIREFIT sticker near the
valve on the wheel with the defective tire. X
Remove filler hose B and plug =
from the
bottom section of the tire inflation
compressor housing.
X Slide the yellow filler hose connector into
the mounting on yellow cap A of tire
sealant bottle : until the plug engages.
X With the sealing rings in front, slide yellow
cap A of tire sealant bottle : into the
mounting of tire inflation compressor ;
until the cap and both hooks engage. X
Remove the cap from valve C on the
faulty
tire.
X Screw filler hose D onto valve.
X Insert plug = into the socket of the
cigarette lighter (

Y page 250) or into a 12 V
power socket in your vehicle (Y page 250).
X Turn the SmartKey to position 1 in the
ignition lock (Y page 135). Flat tire
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Breakdown assistance Z
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shorter. The starting characteristics can be impaired, particularly at low temperatures. Have
the thawed-out battery checked at a qualified specialist workshop.
Do not
start
the vehicle using a rapid charging device. 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:
R The 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.
R You may only jump-start the vehicle when the engine and exhaust system are cold.
R Do not start the engine if the battery is frozen. Let the battery thaw first.
R Jump-starting may only be performed from batteries with a nominal voltage of 12 V.
R Only use jumper cables which have a sufficient cross-section and insulated terminal clamps.
R If 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 battery slightly.
R Make sure that the two vehicles do not touch.
Make sure that:
R the jumper cables are not damaged.
R bare parts of the terminal clamp do not come into contact with other metal parts while the
jumper cables are connected to the battery.
R the jumper cables cannot come into contact with parts which can move when the engine
is running, such as the V-belt pulley or the fan.
X Secure the vehicle by applying the electric parking brake.
X Shift the transmission to position P.
X Turn the SmartKey to position 0 in the ignition lock and remove it.
X Switch off all electrical consumers (e.g. radio, blower, etc.).
X Open the hood (Y page 266).290
Jump-starting
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!
Only secure the
tow rope or tow bar at the
towing eyes. Otherwise, the vehicle could
be damaged.
! Do not use the towing eyes for recovery
purposes as this could damage the vehicle.
If in doubt, recover the vehicle with a crane.
! When towing, pull away slowly and
smoothly. If the tractive power is too high,
the vehicles could be damaged.
! The vehicle can be towed a maximum of
30 miles (50km). The towing speed of
30 mph (50km/h) must not be exceeded.
If the vehicle has to be towed more than
30 miles (50km), the front axle must be
raised or the entire vehicle raised and
transported.
! Do not tow with sling-type equipment.
This could damage the vehicle.
! Vehicles with automatic transmission
must not be started by tow-starting. This
could otherwise damage the transmission.
It is better to have the vehicle transported
than to have it towed.
When towing a vehicle, the transmission must
be in position N.
The battery must be connected and charged.
Otherwise, you:
R cannot turn the SmartKey to position 2 in
the ignition lock
R cannot shift the transmission to position
N.
i Deactivate the automatic locking feature
(Y page 198). You could otherwise be
locked out when pushing or towing the
vehicle. Installing/removing the towing eye
Installing the towing eye X
Remove the towing eye from the stowage
space.
The towing eye is beneath the cargo
compartment floor with

the vehicle tool kit
(Y page 280).
Vehicles with the TIREFIT kit: the towing
eye is beneath the tire inflation
compressor.
X Press the mark on cover : inwards in the
direction of the arrow.
X Take cover : off the opening.
X Screw in and tighten the towing eye
clockwise to the stop.
Removing the towing eye X
Unscrew and remove the towing eye.
X Attach cover : to the bumper and press
until it engages.
X Place the towing eye in the stowage well
beneath the cargo compartment floor
(Y page 280) in the cargo compartment.
X Vehicles with the TIREFIT kit: put back the
tire inflation compressor.292
Towing and tow-starting
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Towing the vehicle with the front axle
raised
! The ignition must be switched off if the
vehicle is being towed with the front axle
raised. Otherwise, ESP®

may intervene and
damage the brake system.
X Turn the SmartKey to position 2 in the
ignition lock.
X When the vehicle is stationary, depress the
brake pedal and keep it depressed.
X Shift the automatic transmission to
position P.
X Release the brake pedal.
X Release the electric parking brake.
X Deactivate automatic locking
(Y page 198).
X Switch on the hazard warning lamps
(Y page 101).
X Turn the SmartKey to position 0 in the
ignition lock and

leave the SmartKey in the
ignition lock.
When towing your vehicle with the front axle
raised, it is important that you observe the
safety instructions ( Y page 291).Towing a vehicle with both axles on
the ground
G
WARNING
The power assistance for the steering and the
brake force booster do not work when the
engine is not running. You will then need
much more effort to brake and steer the
vehicle. Adapt your style of driving
accordingly.
i In order to signal a change of direction
when towing with

the hazard warning lamps
switched on, use the combination switch as
usual. In this case, only the turn signals for
the desired direction flash. When you reset
the combination switch, the hazard
warning lamps start flashing again. The automatic transmission automatically
shifts
to position P

when you open the driver's
or front-passenger door or when you remove
the SmartKey from the ignition lock. In order
to ensure that the automatic transmission
stays in position N when towing the vehicle,
you must observe the following points:
X Make sure that the vehicle is stationary.
X Turn the SmartKey to position 2 in the
ignition lock.
X Depress and hold the brake pedal.
X Shift the automatic transmission to
position N.
X Leave the SmartKey in position 2 in the
ignition lock.
X Release the brake pedal.
X Release the electric parking brake.
X Switch on the hazard warning lamps
(Y page 101).
It is important that you observe the safety
instructions when towing away your vehicle
(Y page 291). Transporting the vehicle
! Only lash the

vehicle down by the wheels
or wheel rims, not by parts of the vehicle
such as axle or steering components.
Otherwise, the vehicle could be damaged.
X Turn the SmartKey to position 2 in the
ignition lock.
X Shift the transmission to position N.
As soon as the vehicle is loaded:
X Prevent the vehicle from rolling away by
applying the electric parking brake.
X Shift the transmission to position P.
X Turn the SmartKey to position 0 in the
ignition lock and remove it.
X Secure the vehicle.
The towing eye can be used to pull the vehicle
onto a trailer or transporter for transporting
purposes. Towing and tow-starting
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Tow-starting (emergency engine
starting)
! Vehicles with automatic transmission
must not be tow-started. You could
otherwise damage the automatic
transmission.
When tow-starting, it is important that you
observe the safety
instructions (Y page 291).Fuses
Important safety notes
G
WARNING
If you manipulate or bridge a faulty fuse or if
you replace it with a fuse with a higher
amperage, the electric cables could be
overloaded. This could result in a fire. There
is a risk of an accident and injury.
Always replace faulty

fuses with the specified
new fuses having the correct amperage.
! Only use fuses that have been approved
for Mercedes-Benz vehicles and which
have the correct fuse rating for the system
concerned. Only use fuses marked with an
"S". Otherwise, components or systems
could be damaged.
The fuses in your vehicle serve to close down
faulty circuits. If a fuse blows, all the
components on the circuit and their functions
stop operating.
Blown fuses must be replaced with fuses of
the same rating, which you can recognize by
the color and value. The fuse ratings are listed
in the fuse allocation chart.
If a newly inserted fuse also blows, have the
cause traced and rectified at a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center. Before changing a fuse
X Secure the vehicle against rolling away
(Y page 149).
X Switch off all electrical consumers.
X Turn the SmartKey to position 0 in the
ignition lock and remove it (Y page 135).
All indicator lamps

in the instrument cluster
must be off.
The fuses are located in various fuse boxes:
R Fuse box in

the engine compartment on the
left-hand side of the vehicle, when viewed
in the direction of travel
R Fuse box in the front-passenger footwell
The fuse allocation chart is on the fuse box in
the front-passenger footwell ( Y page 295). Fuse box in the engine compartment
G
WARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured
by the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood.
! Make sure that

no moisture can enter the
fuse box when the cover is open.
! When closing the cover, make sure that it
is lying correctly on the fuse box. Moisture
seeping in or dirt could otherwise impair
the operation of the fuses. 294
Fuses
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Checking tire pressures manually
To determine and set the correct tire
pressure, proceed as follows:
X
Remove the valve cap of the tire that is to
be checked.
X Press the tire pressure gauge securely onto
the valve.
X Read the tire pressure and compare it with
the recommended value on the Tire and
Loading Information placard on the
B-pillar on the
driver's side of your vehicle.
X If necessary, increase the tire pressure to
the recommended value ( Y page 301).
X If the tire pressure is too high, release air
by pressing down

the metal pin in the valve
using the tip of a pen, for example. Then,
check the tire pressure again using the tire
pressure gauge.
X Screw the valve cap onto the valve.
X Repeat these steps for the other tires. Tire pressure loss warning system
Important safety notes While the vehicle is in motion, the tire
pressure loss warning system monitors the
set
tire
pressure

using the rotational speed of
the wheels. This enables the system to detect
significant pressure loss in a tire. If the speed
of rotation of a wheel changes as a result of
a loss of pressure, a corresponding warning
message will appear in the multifunction
display.
The tire pressure warning system does not
warn you of an incorrectly set tire pressure.
Observe the notes on the recommended tire
pressure ( Y page 301).
The tire pressure loss warning system does
not replace the need to regularly check your
vehicle's tire pressures, since an even loss of
pressure on several tires at the same time
cannot be detected by the tire pressure loss
warning system. The tire pressure loss warning system is not
able to
warn

you of a sudden loss of pressure,
e.g. if the tire is penetrated by a foreign
object. In the event of a sudden loss of
pressure, bring the vehicle to a halt by braking
carefully. Avoid abrupt steering maneuvers.
The function of the tire pressure loss warning
system is limited or delayed if:
R snow chains are mounted to your vehicle's
tires.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style
(cornering at high speeds or driving with
high rates of acceleration).
R you are driving with a heavy load (in the
vehicle or on the roof).
Restarting the tire pressure loss
warning system Restart the tire pressure loss warning system
if you have:
R
changed the tire pressure
R changed the wheels or tires
R mounted new wheels or tires
X Before restarting, make sure that the tire
pressures are set properly on all four tires
for the respective operating conditions.
The recommended tire pressures can be
found in the table on the fuel filler flap.
The tire pressure loss warning system can
only give reliable warnings if you have set
the correct tire

pressure. If an incorrect tire
pressure is set, these incorrect values will
be monitored.
X Observe the notes on tire pressure
(Y page 301).
X Make sure that the SmartKey is in
position 2 (Y page 135)

in the ignition lock. Tire pressure
305
Wheels and tires Z
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