engine MERCEDES-BENZ B-CLASS 2012 User Guide

Protection of the environment
General notes
H
Environmental note
Daimler's declared policy is one of
comprehensive environmental protection.
The objectives are for the natural resources
that form the basis of our existence on this
planet to be used sparingly and in a manner
that takes the requirements of both nature
and humanity into account.
You too can help to protect the environment
by operating your vehicle in an
environmentally responsible manner.
Fuel consumption and the rate of engine,
transmission, brake and
tire wear are affected
by these factors:
R operating conditions of your vehicle
R your personal driving style
You can influence both factors. You should
bear the following in mind:
Operating conditions:
R avoid short trips as these increase fuel
consumption.
R always make sure that the tire pressures
are correct.
R do not carry any unnecessary weight.
R remove roof racks once you no longer need
them.
R a regularly serviced vehicle will contribute
to environmental protection. You should
therefore adhere to the service intervals.
R always have service work carried out at a
qualified specialist workshop.
Personal driving style:
R do not depress the accelerator pedal when
starting the engine.
R do not warm up the engine when the vehicle
is stationary.
R drive carefully and maintain a safe distance
from the vehicle in front.
R avoid frequent, sudden acceleration and
braking. R
change gear in
good time and use each gear
only up to Ô of its maximum engine speed.
R switch off the engine in stationary traffic.
R keep an eye on the vehicle's fuel
consumption. Environmental concerns and
recommendations
Wherever the operating instructions require
you to dispose of materials, first try to
regenerate or re-use them. Observe the
relevant environmental rules and regulations
when disposing of materials. In this way you
will help to protect the environment. Genuine Mercedes-Benz parts
H
Environmental 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.
! 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 cockpit
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. 20
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Have aftermarket accessories installed at
a qualified specialist workshop.
You could jeopardize the operating safety of
your vehicle if
you use parts, tires and wheels
as well as accessories relevant to safety
which have not been approved by Mercedes.
This could lead to malfunctions in safety-
relevant systems, e.g. the brake system. Use
only genuine Mercedes-Benz parts or parts of
equal quality. Only use tires, wheels and
accessories that have been specifically
approved for your vehicle.
Genuine Mercedes-Benz parts are subject to
strict quality control. Every part has been
specifically developed, manufactured or
selected for and adapted to Mercedes-Benz
vehicles. Only genuine Mercedes-Benz parts
should therefore be used.
More than 300,000 different genuine
Mercedes-Benz parts are available for
Mercedes-Benz models.
All authorized 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 quick and reliable
parts service.
Always specify the vehicle identification
number (VIN) ( Y page 328) and the engine
number (Y page 329) when ordering genuine
Mercedes-Benz parts. Operator's Manual
General notes
Before you first

drive off, read this Operator's
Manual carefully and familiarize yourself with
your vehicle.
For your own safety and a longer vehicle life,
follow the instructions and warning notices in
this manual. Disregarding them may lead to
damage to the vehicle or personal injury.
Vehicle damage resulting from the disregard
of the instructions is not covered by the
Mercedes-Benz Limited Warranty. Vehicle equipment
This Operator's Manual describes all models
and all standard and optional equipment of
your vehicle available at the time of going to
print. 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. The

equipment in your vehicle
may therefore differ from some of the
descriptions or illustrations.
The original purchase agreement lists all
systems installed in your vehicle.
Contact an authorized Mercedes-Benz Center
if you have any questions about equipment or
operation.
The Operator's Manual and Maintenance
Booklet are important documents and should
be kept in the vehicle. Service and vehicle operation
Service and literature
Your vehicle is

covered under the terms of the
warranties printed in the Service and
Warranty Information booklet. Your
authorized Mercedes-Benz Center will
exchange or repair any defective parts
originally installed in the vehicle in
accordance with the terms of the following
warranties:
R New Vehicle Limited Warranty
R Emission Systems Warranty
R Emission Performance Warranty
R California, Connecticut, Maine,
Massachusetts, New York, Pennsylvania,
Rhode Island and Vermont Emission
Control Systems Warranty
R State warranty enforcement laws (lemon
laws) Introduction
21 Z
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Maintenance
The Service and Warranty Booklet describes
all the necessary maintenance work which
should be done at regular intervals.
Always have the Service and Warranty
Booklet with you when you bring the vehicle
to an authorized Mercedes-Benz Center. The
service advisor will record every service for
you in the Service and Warranty Booklet. Roadside Assistance
The Mercedes-Benz Roadside Assistance
Program offers technical help in the event of
a breakdown. Calls to the toll-free Roadside
Assistance Hotline are answered by our
agents 24 hours a day, 365 days a year.
1-800-FOR-MERCedes(1-800-367-6372)
(USA)
1-800-387-0100
(Canada)
For additional information, refer to the
Mercedes-Benz Roadside Assistance
Program brochure (USA) or the "Roadside
Assistance" section in the Service and
Warranty booklet (Canada). You will find both
in your vehicle literature portfolio. Change of address or change of
ownership
In the event of a change of address, please
send us the

"Notification of Address Change"
in the Service and Guarantee booklet or
simply call the Mercedes-Benz Customer
Assistance Center (USA) at the hotline
number
1-800-FOR-MERCedes(1-800-367-6372) or
Customer Service Center (Canada) at
1-800-387-0100. This will assist us in
contacting you in a timely manner should the
need arise.
If you sell your Mercedes, please leave the
entire literature in the vehicle so that it is
available to the next owner. If you have purchased a used car, please send
us the
"Notification

of Used Car Purchase" in
the Service and Guarantee booklet or simply
call the Mercedes-Benz Customer Assistance
Center (USA) at the hotline number
1-800-FOR-MERCedes(1-800-367-6372) or
Customer Service (Canada) at
1-800-387-0100. Vehicle operation outside Canada
If you plan to operate your vehicle in foreign
countries, please be aware that:
R service facilities or

replacement parts may
not be readily available.
R unleaded fuel for vehicles with a catalytic
converter may not be available. Leaded fuel
may cause damage to the catalytic
converter.
R the fuel may have a considerably lower
octane rating. Unsuitable fuel can cause
engine damage.
Some Mercedes-Benz models are available
for delivery in Europe through our European
Delivery Program. For details, consult an
authorized Mercedes-Benz Center or write to
one of the following addresses.
In the USA
Mercedes-Benz USA, LLC
European Delivery Department
One Mercedes Drive
Montvale, NJ 07645-0350
In Canada
Mercedes-Benz Canada, Inc.
European Delivery Department
98 Vanderhoof Avenue
Toronto, Ontario M4G 4C9 22
Introduction
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including interference that may cause
undesired operation of the device."
Diagnostics connection
The diagnostics connection is only intended
for the connection
of diagnostic equipment at
a qualified specialist workshop. G
WARNING
If you connect equipment to the diagnostics
connection in the vehicle, it may affect the
operation of the

vehicle systems. As a result,
the operating safety of the vehicle could be
affected. There is a risk of an accident.
Do not connect any equipment to a
diagnostics connection in the vehicle. G
WARNING
Objects in the driver's footwell can restrict the
pedal travel or obstruct a depressed pedal.
The operating and road safety of the vehicle
is jeopardized. There is a risk of an accident.
Make sure that all objects in the vehicle are
stowed correctly, and that they cannot enter
the driver's footwell. Install the floormats
securely and as specified in order to ensure
sufficient clearance for

the pedals. Do not use
loose floormats.
! If the engine is switched off and
equipment on the diagnostics connection
is used, the starter battery may discharge.
Connecting equipment to the diagnostics
connection can lead to emissions monitoring
information being reset, for example. This
may lead to the vehicle failing to meet the
requirements of the next emissions test
during the main inspection. Qualified specialist workshop
An authorized Mercedes-Benz Center is a
qualified specialist workshop. It has the
necessary specialist knowledge, tools and
qualifications to correctly carry out the work required on your vehicle. This is especially the
case for work relevant to safety.
Observe the notes in the Maintenance
Booklet.
Always have
the

following work carried out at
an authorized Mercedes-Benz Center:
R work relevant to safety
R service and maintenance work
R repair work
R alterations, installation work and
modifications
R work on electronic components Correct use
If you remove any warning stickers, you or
others could fail

to recognize certain dangers.
Leave warning stickers in position.
Observe the following information when
driving your vehicle:
R the safety notes in this manual
R the Technical Data section in this manual
R traffic rules and regulations
R laws and safety standards pertaining to
motor vehicles Problems with your vehicle
If you should

experience a problem with your
vehicle, particularly one that you believe may
affect its safe operation, we urge you to
contact an authorized Mercedes-Benz Center
immediately to have the problem diagnosed
and rectified. If the problem is not resolved to
your satisfaction, please discuss the problem
again with a Mercedes-Benz Center or
contact us at one of the following addresses.
In the USA
Customer Assistance Center
Mercedes-Benz USA, LLC
One Mercedes Drive
Montvale, NJ 07645-0350
In Canada 24
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Warning and indicator lamps
Function Page
:
L Low-beam
headlamps
99
;
T Parking lamps
100
=
K High-beam
headlamps
100
?
÷ ESP
® 227
A
! Electric parking brake
(red)
230
B
!
Electric parking brake
(yellow) 230
C
· Distance warning
233
D
#! Turn signals
100 Function Page
E
6 SRS
230
F
ü Seat belt
224
G
? Coolant
231
H
R Rear fog lamp
100
I
N Front fog lamps
99
J
; Check Engine
231
K
æ Reserve fuel
231
L
å ESP
®
OFF 227
M
! ABS
225
N
J Brakes
22530
Instrument clusterAt a glance
ProCarManuals.com

R
Emergency Tensioning Device
for the front
seat belts and the outer seat belts in the
rear
R Seat belt force limiters for the front seat
belts and the outer seat belts in the rear
SRS reduces the risk of occupants coming
into contact with parts of the vehicle's interior
in the event of an accident. It can also reduce
the effect of the forces to which occupants
are subjected during an accident.
SRS warning lamp G
WARNING
The SRS self-check has detected a
malfunction if the 6 SRS indicator lamp:
R does not light up at all
R does not go out after approximately four
seconds after the engine is started
R lights up
after

the engine is started or while
the vehicle is in motion
For your safety, Mercedes-Benz strongly
recommends that you have the system
checked as soon as possible at a qualified
specialist workshop. SRS may otherwise fail
to activate when it is needed in the event of
an accident, which could lead to serious or
fatal injuries. SRS might also be activated
unexpectedly and unnecessarily, which could
also result in injury.
In addition, work carried out improperly on
SRS may render SRS inoperative or cause
unintended air bag deployment. Work on the
SRS system should only be carried out by
qualified specialist personnel. Consult a
qualified specialist workshop.
If it is necessary to modify an air bag system
to accommodate a person with disabilities,
contact an authorized Mercedes-Benz Center
for details. USA only: for further information,
contact our Customer Assistance Center at
1-800-FOR-MERCedes (1-800-367-6372).
The 6 SRS warning lamp in the instrument
cluster lights up when the ignition is switched on. It goes out no later than a few seconds
after the engine is started.
SRS
functions are

checked regularly when the
ignition is switched on or the engine is
running. Therefore, malfunctions can be
detected in good time.
Triggering of Emergency Tensioning
Device and air bags During the first stage of a collision, the air bag
control unit evaluates important physical
data relating to vehicle deceleration or
acceleration, such as:
R
duration
R direction
R magnitude
Based on the evaluation of this data, the air
bag control unit pre-emptively triggers the
Emergency Tensioning Device in the first
stage.
If there is an even higher rate of vehicle
deceleration or acceleration in a longitudinal
direction, the front

air bags are also deployed.
Your vehicle has adaptive, two-stage front air
bags. The air bag control unit evaluates
vehicle deceleration or acceleration in the
event of a collision. In the first deployment
stage, the front air bag is filled with enough
propellant gas to reduce the risk of injuries.
The front air bag is fully deployed if a second
deployment threshold is reached within a few
milliseconds.
The Emergency Tensioning Device and air bag
triggering thresholds are variable and are
adapted to the detected rate of deceleration
or acceleration of the vehicle. This process is
pre-emptive in nature. The triggering process
must take place in good time at the start of
the collision.
The rate of vehicle deceleration or
acceleration and the direction of the force are
essentially determined by:
R the distribution of forces during the
collision
R the collision angle Occupant safety
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Safety Z
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Belt warning for the driver and front
passenger
Regardless of whether the driver's and front-
passenger seat belts have already been
fastened, the 7 seat belt warning lamp
lights up
for
six seconds each time the engine
is started. It then goes out if the driver and
the front passenger have already fastened
their seat belts.
If the driver's seat belt is not fastened when
the engine is started, an additional warning
tone will sound. This warning tone stops after
a maximum of six seconds or once the
driver's seat belt is fastened.
If after six seconds the driver or front
passenger have not fastened their seat belts
and the doors are closed, the 7 seat belt
warning lamp lights up:
R until the driver's or front passenger's seat
belt is fastened
R if a vehicle speed of 15 mph (25 km/h) is
exceeded, a warning tone also sounds with
increasing intensity for a maximum of
60 seconds or until the driver or front-
passenger seat belt has been fastened.
If the driver/front passenger unfasten their
seat belt while the vehicle is in motion, the
7 seat belt warning lamp lights up and a
warning tone sounds again.
The warning tone ceases even if the driver or
front-passenger seat belt has still not been
fastened after 60 seconds. The 7 seat belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated and the 7 seat
belt warning lamp flashes again if the vehicle
speed again exceeds 15 mph (25 km/h).
The 7 seat belt warning lamp only goes
out if:
R both the driver and the front passenger
have fastened their seat belts.
or
R the vehicle is stationary and a door is open. i
For more information on the 7 seat
belt warning lamp, see "Warning and
indicator lamps in the instrument cluster,
seat belts" ( Y page 224).
Emergency Tensioning Devices, seat
belt force limiters G
WARNING
Pyrotechnic ETDs that were activated must be
replaced.
For your safety, when disposing of the
pyrotechnic ETDs always follow our safety
instructions. These are available at any
authorized Mercedes-Benz Center.
! If the front-passenger seat is not
occupied, do not engage the seat belt
tongue in the buckle on the front-
passenger seat. Otherwise,

the Emergency
Tensioning Device could be triggered in the
event of an accident.
The front seat belts and the outer seat belts
in the rear are equipped with Emergency
Tensioning Devices and seat belt force
limiters.
The ETDs tighten the seat belts in an accident,
pulling them close against the body.
The ETDs do not correct incorrect seat
positions or incorrectly fastened seat belts.
The ETDs do not pull vehicle occupants back
towards the backrest.
The ETDs can only be activated when:
R the ignition is switched on.
R the restraint systems are operational; see
"SRS warning lamp" 6(Y page 39).
R the belt tongue is engaged in the buckle on
each of the front seat belts.
The ETDs on the outside seats in the rear
compartment are triggered independently of
the lock status of the seat belts.
The ETDs are triggered depending on the type
and severity of an accident:
R if, in the event of a head-on or rear-end
collision, the vehicle decelerates or Occupant safety
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R
ADAPTIVE BRAKE ( Y
page 64)
(Y page 64)
R STEER CONTROL ( Y page 64)Important safety notes
If you fail to adapt your driving style or
become distracted, the driving safety
systems can neither reduce the risk of
accident nor override the laws of physics.
Driving safety systems are merely aids
designed to assist driving. You are
responsible for the distance to the vehicle in
front, for vehicle speed and for braking in
good time. Always

adapt your driving style to
suit the prevailing road, weather and traffic
conditions and maintain a safe distance from
the vehicle in front. Drive carefully.
i The driving safety systems described only
work as effectively as possible when there
is adequate contact between the tires and
the road surface. Pay particular attention
to the information regarding tires,
recommended minimum tire tread depths
etc. in the "Wheels and tires" section
(Y page 298).
In wintry driving conditions, always use
winter tires (M+S tires) and if necessary,
snow chains. Only in this way will the
driving safety systems described in this
section work as effectively as possible. ABS (Anti-lock Braking System)
Important safety notes i
Observe the "Important safety notes"
section for driving safety systems
(Y page 59). G
WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking
characteristics may be severely impaired.
Additionally, further driving safety systems are deactivated. There is an increased danger
of skidding and accidents.
Drive on carefully. Have ABS checked
immediately at a qualified specialist
workshop.
When ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe

the information
on the ABS warning lamp ( Y page 225) and
display messages which may be shown in the
instrument cluster (Y page 201).
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the
vehicle when braking.
ABS works from a speed of about 5 mph
(8 km/h) upwards, regardless of road-surface
conditions. ABS works on slippery roads,
even if you only brake gently.
The ! ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
Braking X
If ABS intervenes: continue to
depress the
brake pedal vigorously until the braking
situation is over.
X To make a full brake application:
depress the brake pedal with full force.
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
The pulsating brake pedal can be an
indication of hazardous road conditions, and
functions as a reminder to take extra care
while driving. BAS (Brake Assist System)
i Observe the "Important safety notes"
section ( Y page 59). Driving safety systems
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Up to vehicle speeds of around 155 mph
(250 km/h
),
adaptive Brake Assist is capable
of reacting to moving objects that have
already been recognized as such at least once
over the period of observation. Adaptive
Brake Assist does not react to stationary
obstacles.
If Adaptive Brake Assist is not available due
to a malfunction in the radar sensor system,
the brake system remains available with full
brake boosting effect and BAS.
In particular, the detection of obstacles can
be impaired if there is:
R dirt on the sensors or anything else
covering the sensors
R snow or heavy rain
R interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the
vehicle, have the configuration and operation
of the radar sensor checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle. Adaptive brake lights
If you brake sharply from a speed of more
than 50 km/h

or if braking is assisted by BAS
or Adaptive Brake Assist, the brake lamps
flash rapidly. In this way, traffic traveling
behind you is warned in an even more
noticeable manner.
If you brake sharply to a standstill from a
speed of more than 70 km/h, the hazard
warning lamps are activated automatically. If
the brakes are applied again, the brake lamps
light up continuously. The hazard warning
lamps switch off automatically if you travel
faster than 10 km/h. You can also switch off the hazard warning lamps using the hazard
warning button (Y page 101).
i
Adaptive brake lamps

are only available in
certain countries. ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes"
section ( Y page 59).
ESP ®
monitors driving stability and traction,
i.e. power transmission

between the tires and
the road surface.
If ESP ®
detects that the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilize the
vehicle. The engine output is also modified to
keep the vehicle on the desired course within
physical limits. ESP ®
assists the driver when
pulling away on wet or slippery roads. ESP ®
can also stabilize the vehicle during braking.
ETS (Electronic Traction System) i
Observe the "Important safety notes"
section for driving safety systems
(Y page 59).
ETS traction control is part of ESP ®
.
ETS brakes the drive wheels individually if
they spin. This enables you to pull away and
accelerate on slippery surfaces, for example
if the road surface is slippery on one side.
ETS remains active when you deactivate
ESP ®
.
Important safety notes G
WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilize the vehicle. Additionally, further
driving safety systems are deactivated. This
increases the risk

of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop. 62
Driving safety systems
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!
When testing the electric parking brake
on a braking dynamometer, switch off the
ignition. Application of the brakes by
ESP ®
may otherwise destroy the brake
system.
When towing your vehicle with the front axle
raised, observe the notes on
ESP ®
(Y page 293).
ESP ®
is deactivated if the å ESP®
OFF
warning lamp in
the instrument cluster lights
up continuously when the engine is running.
If the ÷ ESP ®
warning lamp and the
å ESP ®
OFF warning lamp are lit
continuously, ESP ®
is not available due to a
malfunction.
Observe the information on warning lamps
(Y page 227) and display messages which
may be shown in the instrument cluster
(Y page 201).
i Only use wheels with the recommended
tire sizes. Only then will ESP ®
function
properly.
Characteristics of ESP ®General information
ESP
®
is activated automatically when the
engine is started.
If ESP ®
intervenes, the ÷ ESP®
warning
lamp flashes in the instrument cluster.
If ESP ®
intervenes:
X Do not deactivate ESP ®
under any
circumstances.
X Only depress the accelerator pedal as far
as necessary when pulling away.
X Adapt your driving style to suit the
prevailing road and weather conditions.
Vehicles with the ECO start/stop function Deactivating/activating ESP
® Important safety notes
i
Observe the "Important safety notes"
section for driving safety systems
(Y page 59).
You can select between the following states
of ESP ®
:
R ESP ®
is activated.
R ESP ®
is deactivated. G
WARNING
If you deactivate ESP ®
, ESP ®
no longer
stabilizes the vehicle. There is an increased
risk of skidding and an accident.
Only deactivate ESP ®
in the situations
described in the following.
It may be best to deactivate ESP ®
in the
following situations:
R when using snow chains
R in deep snow
R on sand or gravel
i Activate ESP ®
as soon as the situations
described above no

longer apply. ESP®
will
otherwise not be able to stabilize the
vehicle if the vehicle starts to skid or a
wheel starts to spin.
! Avoid spinning the driven wheels for an
extended period with ESP ®
deactivated.
You could otherwise damage the drivetrain.
Deactivating/activating ESP ®
You can deactivate or activate ESP ®
via the
on-board computer.
X To deactivate: (Y page 194).
The å ESP ®
OFF warning lamp in the
instrument cluster lights up.
X To activate: (Y page 194).
The å ESP ®
OFF warning lamp in the
instrument cluster goes out. Driving safety systems
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