ECU MERCEDES-BENZ B-CLASS HATCHBACK 2015 Owner's Manual

Suitability of the seats for attaching ISOFIX child restraint systems
If you use a baby car seat of category 0 or 0+ or a rearward-facing child restraint system of category
I on a rear seat, you must adjust the driver's or front-passenger seat so that the seat does not touch the child restraint system.
If you use a category I, forward-facing child restraint system, you should remove the head restraint
of the respective seat (Y page 90), if possible. The backrest of the child restraint system must, as
far as possible, lie flat against the backrest of the seat.
Always observe the notes in the "Child restraint system" section (Y page 49) and the child restraint
system manufacturer's installation instructions.
When you remove the child restraint system you must replace the head restraints again immediately
(Y page 89). All vehicle occupants must adjust their head restraints correctly before beginning the
journey.
Legend for the table:
XI SOFIX position that is not suitable for ISOFIX child restraint systems in this weight category
and/or size category.
IUF Suitable for forward-facing ISOFIX child seat securing systems that belong to the "Universal" category which are approved for use in this weight category.
IL Suitable for ISOFIX child restraint systems as recommended; see the "Recommended child restraint systems" table (Y page 58).
The manufacturer will also recommend a suitable ISOFIX child restraint system. For this, your vehicle and the seat must be listed in the child restraint system manufacturer's model list. For
more information, contact the child restraint system manufacturer or visit their website. Weight category Size category Equipment Rear seat left,
right Carry-cot
F ISO/L1 X
G ISO/L2 X
0
up to 10 kg
up to approximately 6 months E ISO/R1 IL
0+
up to 13 kg
up to approximately 15 months E ISO/R1 IL
D ISO/R2 IL
C ISO/R3
IL
3 I
9 kg to 18 kg
between approximately 9 months
and 4 years D ISO/R2 IL
C ISO/R3
IL
3 B ISO/F2 IUF
B1 ISO/F2X IUF
A ISO/F3 IUF
The child restraint system must not touch the roof or be put under strain by the head restraints.
Adjust the head restraint position accordingly. Also observe the child restraint system manufac-
turer's installation instructions.
3 If you are using a child restraint system of size category C (ISO/R3), make sure that the front seat backrest
does not rest against the child restraint system. Children in the vehicle
57Safety Z

Child-proof locks
Important safety notes G
WARNING
If children are travelling in the vehicle, they
could:
R open doors, thus endangering other people
or road users
R exit the vehicle and be caught by oncoming
traffic
R operate vehicle equipment and become
trapped, for example
There is a risk of an accident and injury.
Always activate the child-proof locks and
override feature if children are travelling in the vehicle. When leaving the vehicle, always take the key with you and lock the vehicle. Never
leave children unattended in the vehicle.
Override feature for:
R the rear doors (Y page 60)
R the rear side windows (Y page 61)G
WARNING
If you leave children unattended in the vehi-
cle, they may be able to set the vehicle in
motion, for example, if they:
R release the parking brake
R shift the transmission out of park position P
R start the vehicle's drive system
In addition, they may operate vehicle equip-
ment. There is a risk of an accident and injury.
When leaving the vehicle, always take the key
with you and lock the vehicle. Never leave
children unattended in the vehicle. G
WARNING
If persons (particularly children) are exposed
to heat or cold for a prolonged period, there is a risk of serious or even fatal injuries. Never
leave persons (particularly children) unatten-
ded in the vehicle. G
WARNING
If the child restraint system is placed in direct sunlight, the parts could become very hot.
Children could be suffer burns by touching
these parts, in particular on the metallic parts
of the child restraint system. There is a risk of injury.
If you and your child leave the vehicle, always
make sure that the child restraint system is
not in direct sunlight. Cover it with a blanket, for example. If the child restraint system has
been exposed to direct sunlight, leave it to
cool down before securing the child in it.
Never leave children unattended in the vehi-
cle.
Child-proof locks for the rear doors You secure each door individually with the child-
proof locks on the rear doors. A door secured
with a child-proof lock cannot be opened from
inside the vehicle. When the vehicle is unlocked, the door can be opened from the outside.
X To activate: press the child-proof lock lever
up in the direction of arrow :.
X Make sure that the child-proof locks are work-
ing properly.
X To deactivate: press the child-proof lock
lever down in the direction of arrow ;.60
Children in the vehicleSafety

Override feature for the rear side win-
dows X
To enable/disable: press button:.
If indicator lamp ;is lit, operation of the rear
side windows is disabled. Operation is only
possible using the switches in the driver's
door. If indicator lamp ;is off, operation is
possible using the switches in the rear com-
partment. Pets in the vehicle
G
WARNING
If you leave animals unsupervised or unse-
cured in the vehicle, they may push a button
or a switch, for example.
They could:
R activate vehicle equipment and become
trapped, for example
R switch vehicle systems on or off, thus
endangering other road users
In the event of an accident, sudden braking or
abrupt changes of direction, unsecured ani-
mals could be flung around the vehicle, injur-
ing the vehicle occupants. There is a risk of an accident and injury.
Never leave animals unattended in the vehi-
cle. Always secure animals correctly during a
journey, e.g. in an animal transport box. Driving safety systems
Driving safety systems overview
In this section, you will find information about
the following driving safety systems:
R ABS (A nti-lock Braking System)
(Y page 61)
R BAS (Brake AssistSystem) (Y page 62)
R COLLISION PREVENTION ASSIST PLUS
(Y page 62)
R Adaptive brake lights (Y page 65)
R ESP ®
(Electronic StabilityProgram)
(Y page 65)
R EBD (e lectronic brake force distribution)
(Y page 66)
R ADAPTIVE BRAKE (Y page 67)
R STEER CONTROL (Y page 67) Important safety notes
If you fail to adapt your driving style or if you are
inattentive, the driving safety systems can nei-
ther reduce the risk of an accident nor override
the laws of physics. Driving safety systems are
merely aids designed to assist driving. You are
responsible for maintaining the distance to the
vehicle in front, for vehicle speed, for braking in
good time, and for staying in lane. Always adapt your driving style to suit the prevailing road and weather conditions and maintain a safe distance
from the vehicle in front. Drive carefully.
The driving safety systems described only work as effectively as possible when there is ade-
quate contact between the tyres and the road
surface. Please pay special attention to the
notes on tyres, recommended minimum tyre
tread depths etc. (Y page 266).
In wintry driving conditions, always use winter
tyres (M+S tyres) and, if necessary, snow
chains. Only in this way will the driving safety
systems described in this section work as effec-
tively as possible. ABS (Anti-lock Braking System)
General notes ABS regulates brake pressure in such a way that
the wheels do not lock when you brake. This Driving safety systems
61Safety Z

You should therefore adapt your driving style
to the different handling characteristics. Have the brake system checked at a qualified spe-
cialist workshop.
Observe information regarding indicator and
warning lamps (Y page 216) as well as display
messages (Y page 192). ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety and
offers increased braking comfort. In addition to
the braking function, ADAPTIVE BRAKE also has
the HOLD function (Y page 154) and hill start
assist (Y page 128). STEER CONTROL
General notes STEER CONTROL helps you by transmitting a
noticeable steering force to the steering wheel
in the direction required for vehicle stabilisation.
This steering support is provided in particular if:
R both right wheels or both left wheels are on a
wet or slippery road surface when you brake
R the vehicle starts to skid
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 61).
No steering support is provided from STEER
CONTROL, if: R ESP ®
is malfunctioning
R the steering is faulty
If ESP ®
is malfunctioning, you will be assisted
further by the electrical power steering. Recuperative Brake System
G
WARNING
In the event of malfunctions in the Recupera- tive Brake System, the following may occur: R
the braking performance of the electric
motor may be either reduced or not effec-
tive
R brake pedal resistance may be lower than
usual
R pedal travel may be longer than usual
If you do not make an additional effort to apply the brake yourself, the braking effect may not
be sufficient. There is a risk of an accident.
In the event of a malfunction, depress the
brake pedal further. The brake system is still
fully functional.
Observe the important safety notes on driving
safety systems (Y page 61).
The Recuperative Brake System converts the
kinetic energy when braking into electrical
energy. The electric motor is used as an alter-
nator during braking. This electrical energy is
then stored in the high-voltage battery.
You can find information about manually adjust- able recuperation under "Steering wheel gear-
shift paddles" (Y page 132).
If the warning light in the instrument cluster is lit up, there is a motor malfunction or a brake mal-
function.
Observe information regarding indicator and
warning lamps (Y page 215) as well as display
messages (Y page 190). Protection against theft
Immobiliser
The immobiliser prevents your vehicle from
being started without the correct key.
X To activate with the key: remove the key
from the ignition lock.
X To activate with KEYLESS-GO start func-
tion or KEYLESS-GO:
switch the ignition off
and open the driver's door.
X To deactivate: switch on the ignition.
When leaving the vehicle, always take the key
with you and lock the vehicle. Anyone can start
the drive system if a valid key has been left
inside the vehicle.
i The immobiliser is always deactivated when
you start the drive system. Protection against theft
67Safety Z

Useful information
i This Owner's Manual describes all models,
series and optional equipment for your vehi-
cle that were available at the time of going to
press. National variations are possible. Note
that your vehicle may not be equipped with all
of the functions described. This is also the
case for systems and functions relevant to
safety.
i Read the information on qualified specialist
workshops: (Y page 23). Key
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle, they could:
R open doors, thereby endangering other per-
sons or road users
R get out and be struck by oncoming traffic
R operate vehicle equipment and become
trapped, for example
In addition, the children could also set the
vehicle in motion by, for example:
R releasing the parking brake
R shifting the transmission out of park posi-
tion P
R starting the vehicle's drive system
There is a risk of an accident and injury.
When leaving the vehicle, always take the key with you and lock the vehicle. Never leave
children and animals unattended in the vehi-
cle. Keep the keys out of the reach of children. G
WARNING
If you attach heavy or large objects to the key, the key could be unintentionally turned in the
ignition lock. This could cause the engine to
be switched off. There is a risk of an accident.
Do not attach any heavy or large objects to the
key. Remove any bulky keyrings before insert-
ing the key into the ignition lock. !
Keep the key away from strong magnetic
fields. Otherwise, the remote control function could be affected.
Strong magnetic fields can occur in the vicin-
ity of powerful electrical installations.
Do not keep the key: R with electronic devices, e.g. a mobile phone
or another key
R with metallic objects, e.g. coins or metal film
R inside metallic objects, e.g. a metal case
Vehicles with KEYLESS-GO start function: do
not keep the key in the luggage compartment.
Otherwise, the key may not be detected, e.g.
when starting the drive system using the Start/
Stop button.
United Kingdom only: G
WARNING
When the double locks are activated, the
doors can no longer be opened from the
inside. People in the vehicle can no longer get out, e.g. in hazardous situations. There is a
risk of injury.
Therefore, do not leave any people unsuper-
vised in the vehicle, particularly children, eld-
erly people or people in need of special assis-
tance. Do not activate the double lock when
people are in the vehicle.
If the vehicle has been locked from the outside, the double lock function is activated as stand-
ard. It is then not possible to open the doors
from inside the vehicle. You can deactivate the
double lock function by deactivating the interior
motion sensor (Y page 69). The doors can then
be opened from the inside after the vehicle has
been locked from the outside. You can open the rear doors from inside the vehicle if they are not
secured by the child-proof locks (Y page 60).
The anti-theft alarm system is triggered if the
door is opened from the inside. Switch off the
alarm (Y page 68). G
WARNING
If persons (particularly children) are exposed
to heat or cold for a prolonged period, there is a risk of serious or even fatal injuries. Never
leave persons (particularly children) unatten-
ded in the vehicle. Key
71Opening and closing Z

Doors
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle, they could:
R open doors, thereby endangering other per-
sons or road users
R get out and be struck by oncoming traffic
R operate vehicle equipment and become
trapped, for example
In addition, the children could also set the
vehicle in motion by, for example:
R releasing the parking brake
R shifting the transmission out of park posi-
tion P
R starting the vehicle's drive system
There is a risk of an accident and injury.
When leaving the vehicle, always take the key with you and lock the vehicle. Never leave
children and animals unattended in the vehi-
cle. Keep the keys out of the reach of children.
Stow luggage or loads preferably in the luggage compartment. Observe the loading guidelines
(Y page 224).
United Kingdom only: G
WARNING
When the double locks are activated, the
doors can no longer be opened from the
inside. People in the vehicle can no longer get out, e.g. in hazardous situations. There is a
risk of injury.
Therefore, do not leave any people unsuper-
vised in the vehicle, particularly children, eld-
erly people or people in need of special assis-
tance. Do not activate the double lock when
people are in the vehicle.
If the vehicle has been locked with the key, the
double lock function is activated as standard. It
is then not possible to open the doors from
inside the vehicle. You can deactivate the dou-
ble lock function by deactivating the interior
motion sensor (Y page 69). The doors can then
be opened from the inside after the vehicle has been locked from the outside. You can open the
rear doors from inside the vehicle if they are not secured by the child-proof locks (Y page 60).
The anti-theft alarm system is triggered if the
door is opened from the inside. Switch off the
alarm (Y page 68). Unlocking and opening the doors
from the inside
X
Pull door handle ;.
If the door is locked, locking knob :pops up.
The door is unlocked and opens.
For all countries except the United Kingdom:
You can open a door from inside the vehicle
even if it has been locked. You can only open the rear doors from inside the vehicle if they are not secured by the child-proof locks (Y page 60).
If the vehicle has previously been locked with
the key from the outside, opening a door from
the inside will trigger the anti-theft alarm sys-
tem. Switch off the alarm (Y page 68).
United Kingdom only: G
WARNING
When the double locks are activated, the
doors can no longer be opened from the
inside. People in the vehicle can no longer get out, e.g. in hazardous situations. There is a
risk of injury.
Therefore, do not leave any people unsuper-
vised in the vehicle, particularly children, eld-
erly people or people in need of special assis-
tance. Do not activate the double lock when
people are in the vehicle.
If the vehicle has been locked from the outside, the double lock function is activated as stand-
ard. It is then not possible to open the doors 78
DoorsOpening and closing

from inside the vehicle. You can deactivate the
double lock function by deactivating the interior
motion sensor (Y page 69). The doors can then
be opened from the inside after the vehicle has been locked from the outside. You can open the
rear doors from inside the vehicle if they are not
secured by the child-proof locks (Y page 60).
The anti-theft alarm system is triggered if the
door is opened from the inside. Switch off the
alarm (Y page 68). Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle from
the inside. This can be useful if you wish to lock the vehicle before pulling away, for example. X
To unlock: press button :.
X To lock: press button ;.
If all the doors and the tailgate are closed, the
vehicle locks.
This does not lock or unlock the charge socket
flap.
You cannot unlock the vehicle centrally from the
inside if the vehicle has been locked with the key or KEYLESS-GO.
For all countries except the United Kingdom:
You can open a door from inside the vehicle
even if it has been locked.
If the vehicle has previously been locked with
the key from the outside, opening a door from
the inside will trigger the anti-theft alarm sys-
tem. Switch off the alarm (Y page 68).
You can open the rear doors from inside the
vehicle if they are not secured by the child-proof locks (Y page 60). When a locked door is opened from inside the
vehicle, the previous unlocking process will be
observed if the vehicle has been:
R locked with the locking button for the central
locking or
R locked automatically
The vehicle will be fully unlocked if it had previ-
ously been fully unlocked. Only the door which
has been opened from the inside is unlocked if
only the driver's door had been previously
unlocked.
Only for the United Kingdom: if the vehicle
has been locked with the key, the double lock
function is activated as standard. It is then not
possible to open the doors from inside the vehi-
cle. You can deactivate the double lock function by deactivating the interior motion sensor
(Y page 69). The doors can then be opened from
the inside after the vehicle has been locked from
the outside. You can open the rear doors from
inside the vehicle if they are not secured by the child-proof locks (Y page 60). The anti-theft
alarm system is triggered if the door is opened
from the inside. Switch off the alarm
(Y page 68).
When a locked door is opened from inside the
vehicle, the previous unlocking process will be
observed if the vehicle has been:
R locked with the locking button for the central
locking or
R locked automatically
The vehicle will be fully unlocked if it had previ-
ously been fully unlocked. Only the door which
has been opened from the inside is unlocked if
only the driver's door had been previously
unlocked. Automatic locking feature Doors
79Opening and closing Z

i
If you lock the vehicle as described above,
the charge socket flap is not locked. The anti-
theft alarm system is not primed. Luggage compartment
Important safety notes
G
WARNING
If objects, luggage or loads are not secured or not secured sufficiently, they could slip, tip
over or be flung around and thereby hit vehicle
occupants. There is a risk of injury, especially when braking or abruptly changing directions.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey.
! The tailgate swings upwards and to the rear
when opened. Therefore, make sure that
there is sufficient clearance above and behind
the tailgate.
The opening dimensions of the tailgate can be
found in the "Vehicle data" section
(Y page 284).
Stow luggage or loads preferably in the luggage
compartment. Observe the loading guidelines
(Y page 224).
Do not leave the key in the luggage compart-
ment. You could otherwise lock yourself out.
The tailgate can be:
R opened and closed manually from outside
R emergency release activated from the inside Opening/closing from the outside
Opening X
Press the %button on the key.
X Pull handle :.
X Raise the tailgate.
Closing X
Pull the tailgate down using handle :.
X Let the tailgate to drop into the lock.
X If necessary, lock the vehicle with the &
button on the key or with KEYLESS-GO. Tailgate emergency release
General notes !
The tailgate swings upwards and to the rear
when opened. Therefore, make sure that
there is sufficient clearance above and behind
the tailgate.
The opening dimensions of the tailgate can be
found in the "Vehicle data" section
(Y page 284). Luggage compartment
81Opening and closing Z

Useful information
i This Owner's Manual describes all models,
series and optional equipment for your vehi-
cle that were available at the time of going to
press. National variations are possible. Note
that your vehicle may not be equipped with all
of the functions described. This is also the
case for systems and functions relevant to
safety.
i Read the information on qualified specialist
workshops: (Y page 23). Running-in notes
In certain driving and driving safety systems, the sensors adjust automatically while a certain dis-
tance is being driven after the vehicle has been delivered or after repairs. Full system effective- ness is not reached until the end of this teach-in
process.
Brake pads/linings and discs that are either new or have been replaced only achieve optimum
braking effect after several hundred kilometres
of driving. Compensate for the reduced braking
effect by applying greater force to the brake
pedal. Driving
Important safety notes
G
WARNING
Objects in the driver's footwell may restrict
the clearance around the pedals or block a
depressed pedal. This jeopardises the oper-
ating and road safety of the vehicle. There is a risk of an accident.
Stow all objects securely in the vehicle so that
they do not get into the driver's footwell.
Always fit the floormats securely and as pre-
scribed in order to ensure that there is always sufficient room for the pedals. Do not use
loose floormats and do not place several floor- mats on top of one another. G
WARNING
Unsuitable footwear can hinder correct usage of the pedals, e.g.:
R shoes with thick soles
R shoes with high heels
R slippers
There is a risk of an accident.
Wear suitable footwear to ensure correct
usage of the pedals. G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect, for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk of an accident.
Do not switch off the ignition while driving. G
WARNING
If the parking brake has not been fully
released when driving, the parking brake can:
R overheat and cause a fire
R lose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
! Before driving away, you must ensure that,
for your own safety and to avoid damage, the charging cable has been removed from the
vehicle socket. Otherwise, you cannot shift
the transmission out of position P.
The braking performance of the electric motor
using recuperative braking is, in some operating modes, either reduced or not effective:
R when the charge status of the high-voltage
battery increases
R if the high-voltage battery is not yet at a nor-
mal operating temperature
R when driving close to the maximum speed
R when the vehicle is almost stationary
R in transmission position N
R during and after ESP stability control
If you do not make an additional effort to apply
the brake yourself, the braking effect may not be Driving
125Driving and parking Z

Drive program S (Sport)
Drive program
Sis characterised by the follow-
ing:
R the vehicle exhibits sporty driving character-
istics
R the entire power output can be utilised by
depressing the accelerator pedal.
E+ (Economy Plus) Drive program
E+is characterised by the fol-
lowing:
R reduced torque and significantly reduced
power. This supports an especially efficient
and even driving style and results in a reduc-
tion in speed to approximately 110 km/h.
R the vehicle pulling away more gently in
forward gear unless the accelerator pedal is
depressed fully.
R the wheels are less likely to spin.
R particularly efficient overrun.
R full power output by using kickdown.
R the performance of the air-conditioning and
heating systems is reduced. Steering wheel gearshift paddles
Manually adjustable recuperation :
Left-hand steering wheel gearshift paddle -
; Right-hand steering wheel gearshift paddle
+
You can increase or reduce recuperation in over-
run mode using the steering wheel gearshift
paddles. When you remove your foot from the
accelerator pedal, recuperation occurs. The
electric motor is then used as a alternator and
energy is recovered while driving. The recuper- ated electrical energy is stored in the high-volt-
age battery. A higher energy recuperation level
means that the vehicle is braked more power-
fully.
If necessary, counteract the reduced regenera-
tive braking effect by applying the brake your-
self.
Information on the Recuperative Braking Sys-
tem (Y page 67).
X To decrease recuperation: pull right-hand
steering wheel gearshift paddle ;.
X To increase recuperation: pull left-hand
steering wheel gearshift paddle :.
The various recuperation levels are shown in the
transmission position display once Dhas been
selected (Y page 129).
The following recuperation levels are available in
overrun mode:
R no recuperation (D +
, coasting mode)
R moderate recuperation ( D)
R high recuperation ( D-
)
R recuperation depending on the traffic situa-
tion (D AUTO
, radar-based)
You can see the intensity of recuperation in
overrun mode by reading the recuperation per-
formance value shown in the power display
(Y page 173).
Every time drive position Dis selected, the
transmission switches into recuperation level
D AUTO
automatically.
The various different levels are to be used under the following conditions: D
+ Driving without much braking and
without the presence of obstacles
or sharp bends
The vehicle retains the maximum
possible amount of kinetic
energy. D
Normal driving132
TransmissionDriving and pa
rking