2012 MERCEDES-BENZ A-CLASS HATCHBACK brake light

Function Page
:
Overhead control panel 36
;
PARKTRONIC warning dis-
play 182
=
Combination switch 107
?
Instrument cluster 30
A
Horn
B
DIRECT SELECT lever 151
C
Steering wheel gearshift
paddles
156
D
Light switch 105 Function Page
E
Electric parking brake 163
F
Opening the bonnet 285
G
Diagnostics connection 23
H
Ignition lock 143
I
Adjusting the steering
wheel
98
J
Cruise control lever 169
K
Climate control systems 122Cockpit
29At a glance

PRE-SAFE
®
takes pre-emptive measures to
protect occupants in certain hazardous sit-
uations.
PRE-SAFE ®
intervenes:
R when BAS activates, e.g. in emergency
braking situations
R when adaptive Brake Assist intervenes
powerfully on vehicles with DISTRONIC
PLUS
R in critical driving situations, e.g. when phys-
ical limits are exceeded and the vehicle
understeers or oversteers severely
PRE-SAFE ®
takes the following measures
depending on the hazardous situation detec-
ted:
R the front seat belts are pre-tensioned.
R vehicles with the memory function: the
front-passenger seat is adjusted if it is in an
unfavourable position.
R if the vehicle skids, the panorama sliding
sunroof and the side windows are closed so that only a small gap remains.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pretensioning. All settings made by
PRE-SAFE ®
can then be reversed.
If the seat belts are not released:
X Move the backrest or seat back slightly, but
only when the vehicle is stationary.
The belt pretensioning is reduced and the
locking mechanism is released.
More information about seat belt adjustment,
a convenience function integrated into PRE-
SAFE (Y page 47). Seat belts
Important safety notes G
WARNING
A seat belt which is not worn correctly, or
which has not been engaged in the seat belt
buckle correctly, cannot provide the intended level of protection. Under certain circumstan- ces, this could cause severe or even fatal inju-
ries in the event of an accident.
Therefore, make sure that all occupants — in
particular, pregnant women — wear their seat
belts correctly at all times.
R The seat belt must fit snugly on your body
and must not be twisted. Therefore, avoid
wearing bulky clothing, e.g. a winter coat.
The shoulder section of the belt must be
routed across the centre of your shoulder — on no account across your neck or under
your arm — and pulled tight against your
upper body. The lap belt must always pass
across your lap as low down as possible, i.e.
over your hip joints — not across your abdo- men. If necessary, push the seat belt
slightly downwards and adjust it by pulling
it in the direction the seat belt retracts.
R Do not route the seat belt strap over sharp
or fragile objects. Please make sure that
such objects are not on or in your clothing,
e.g. spectacles, pens or keys etc. The seat
belt strap could become damaged and tear
during an accident and you or other vehicle occupants could be injured.
R Only one person should use each seat belt
at any one time. Children must never travel
sitting on the lap of another occupant. The
child will not be secured in the event of an
accident, heavy braking or sudden change
of direction. This may result in the child or
other occupants being seriously or fatally
injured.
R Persons under 1.50 mtall cannot wear the
seat belts correctly. For this reason secure persons less than 1.50 m tall in specially
designed, suitable restraint systems.
R Children under 1.50 m tall and younger
than twelve years of age cannot wear the
seat belts correctly. For this reason secure
them in special suitable child restraint sys-
tems installed on a suitable seat. Additional
information can be found in the Operating
Instructions in the chapter "Safety", "Chil-
dren in the Vehicle". Observe the installa- 46
Occupant safetySafety

ally, further driving safety systems are deac-
tivated. There is an increased danger of skid- ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
If ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information on the ABS warning lamp (Y page 258) and
display messages which may be shown in the
instrument cluster (Y page 230).
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the vehi-
cle when braking.
ABS works from a speed of about 8 km/h
upwards, regardless of road-surface condi-
tions. ABS works on slippery surfaces, even
when 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 with force until the braking sit- uation 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 indica-
tion of hazardous road conditions, and func-
tions as a reminder to take extra care while
driving. BAS (Brake Assist)
i Observe the "Important safety notes" sec-
tion (Y page 61). G
WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
BAS operates in emergency braking situa-
tions. If you depress the brake pedal quickly,
BAS automatically boosts the braking force,
thus shortening the stopping distance.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. COLLISION PREVENTION ASSIST
General notes COLLISION PREVENTION ASSIST consists of
the adaptive Brake Assist and the distance
warning signal, which are described in the
following.
Distance warning function Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 61). G
WARNING
The distance warning function does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
Thus, the distance warning function cannot
provide a warning in all critical situations.
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake. G
WARNING
The distance warning function cannot always
clearly identify objects and complex traffic
situations. 62
Driving safety systemsSafety

In such cases, the distance warning function
may:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation; do not rely on the distance warning
function alone.
Function X To activate/deactivate: activate or deac-
tivate the distance warning function in the
on-board computer (Y page 218).
Vehicles with a black and white multi-
function display: when the distance warning
function is activated, the Äsymbol
appears in the status overview in the multi-
function display.
Vehicles with a colour multifunction dis-
play: when the distance warning function is
deactivated, the æsymbol appears in the
assistance graphics in the multifunction dis-
play.
The distance warning function can help you to
minimise the risk of a front-end collision with a vehicle ahead or reduce the effects of such
a collision. If the distance warning function
detects that there is a risk of a collision, you
will be warned visually and acoustically. With- out your intervention, the distance warning
function cannot prevent a collision.
The distance warning function issues a warn- ing at speeds:
R of around 30 km/h or more, if, over several
seconds, the distance maintained to the
vehicle travelling in front is insufficient. The · distance warning lamp then lights up
in the instrument cluster.
R of around 7 km/h or higher, if you very
quickly approach a vehicle in front. An
intermittent warning tone will then sound,
and the ·distance warning lamp will
light up in the instrument cluster. X
Brake immediately in order to increase the
distance from the vehicle in front.
or
X Take evasive action provided it is safe to do
so.
Due to the nature of the system, particularly
complicated but non-critical driving condi-
tions may also cause the system to display a
warning.
With the help of the radar sensor system, the distance warning function can detect obsta-
cles that are in the path of your vehicle for an
extended period of time.
Up to a speed of around 70 km/h, the dis-
tance warning function can also react to sta-
tionary obstacles, such as stopped or parked vehicles.
If you approach an obstacle and the distance
warning function detects a risk of a collision,
the system will alert you both visually and
acoustically.
In particular, the detection of obstacles can
be impaired in the case of:
R dirt on the sensors or obscured sensors
R snow or heavy rain
R interference by other radar sources
R strong radar reflections, for example, in
multi-storey car parks
R a narrow vehicle travelling in front, e.g. a
motorcycle
R a vehicle travelling in front on a different
line
Following damage to the front end of the vehi- cle, have the configuration and operation of
the radar sensor checked at a qualified spe-
cialist workshop. This also applies to colli-
sions at slow speeds where there is no visible
damage to the front of the vehicle.
Adaptive Brake Assist i
Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 61). Driving safety systems
63Safety Z

or adaptive Brake Assist, the brake lamps
flash rapidly. In this way, traffic travelling
behind you is warned in an even more notice-
able manner.
If you brake sharply from a speed of more
than 70 km/ht o a standstill, the hazard warn-
ing 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 switch button (Y page 108).
i Adaptive brake lamps are only available in
certain countries. ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes" sec-
tion (Y page 61).
ESP ®
monitors driving stability and traction,
i.e. power transmission between the tyres
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 stabilise 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 stabilise the vehicle during braking.
ETS/4ETS (Electronic Traction System) i
Observe the "Important safety notes" sec-
tion (Y page 61).
ETS/4ETS 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. In
addition, more drive torque is transferred to
the wheel or wheels with traction. ETS remains active when you deactivate
ESP
®
.
Important safety notes G
WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilise the vehicle. In addition, other driving
safety systems are switched off. This increa-
ses the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
! 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.
! Vehicles with 4MATIC: switch off the igni-
tion when the electric parking brake is
being tested using a dynamometer.
Application of the brakes by ESP ®
may oth-
erwise destroy the brake system.
! Vehicles with 4MATIC: function or per-
formance tests may only be carried out on
a 2-axle dynamometer. Before operating
the vehicle on such a dynamometer, please
consult a qualified specialist workshop.
You could otherwise damage the drive train
or the brake system.
! Do not tow vehicles with 4MATIC with the
front or rear axle raised.
Vehicles without 4MATIC: when towing your
vehicle with the front axle raised, it is impor-
tant that you observe the notes on
ESP ®
(Y page 312).
Vehicles with 4MATIC: when towing your
vehicle with both axles on the ground, it is
important that you observe the notes on
ESP ®
(Y page 312).
ESP ®
is deactivated if the åESP®
OFF
warning lamp in the instrument cluster lights up continuously when the engine is running. Driving safety systems
65Safety Z

Deactivating/activating ESP
®X
To activate SPORT handling mode:
briefly press button :.
The M handling mode warning lamp in
the instrument cluster lights up. The
SPORT handling mode
SPORT handling mode message appears
in the multifunction display.
X To deactivate SPORT handling mode:
briefly press button :.
The M handling mode warning lamp in
the instrument cluster goes out.
X To deactivate ESP ®
:press button :until
the å ESP®
OFF warning lamp lights up
in the instrument cluster.
The ÷OFF OFFmessage appears in the mul-
tifunction display.
X To activate ESP ®
:briefly press button :.
The å ESP®
OFF warning lamp in the
instrument cluster goes out. The ÷
ESP ®
ON
ON message appears in the multifunc-
tion display.
Characteristics of activated SPORT han-
dling mode
If SPORT handling mode is activated and one
or more wheels start to spin, the ÷ESP®
warning lamp in the instrument cluster
flashes. ESP ®
only stabilises the vehicle to a
limited degree.
When SPORT handling mode is activated:
R ESP ®
only improves driving stability to a
limited degree.
R traction control is still activated. R
engine torque is restricted to a limited
degree and the drive wheels are able to
spin.
The spinning of the wheels results in a cut-
ting action for better traction on loose sur- faces.
R ESP ®
still provides support when you
brake.
Characteristics when ESP ®
is deactivated
If ESP ®
is deactivated and one or more wheels
start to spin, the ÷ESP®
warning lamp in
the instrument cluster does not flash. In such
situations, ESP ®
will not stabilise the vehicle.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R engine torque is no longer limited and the
drive wheels are able to spin.
The spinning of the wheels results in a cut-
ting action for better traction on loose sur-faces.
R traction control is still activated.
R PRE-SAFE ®
is no longer available; nor is it
activated if you brake firmly with assis-
tance from ESP ®
.
R COLLISION PREVENTION ASSIST is no lon-
ger available; nor is it activated if you brake
firmly with assistance from ESP ®
.
R COLLISION PREVENTION ASSIST is no lon-
ger available; nor is it activated if you brake
firmly with assistance from ESP ®
.
R ESP ®
still provides support when you
brake.
Deactivating/activating ESP ®
(except
AMG vehicles) Important safety notes
You can select between the following states
of ESP
®
:
R ESP ®
is activated.
R ESP ®
is deactivated. Driving safety syste
ms
67Safety Z

G
WARNING
If you deactivate ESP ®
, ESP ®
no longer sta-
bilises the vehicle. There is an increased risk
of skidding and an accident.
Only deactivate ESP ®
in the situations descri-
bed in the following.
It may be best to deactivate ESP ®
in the fol-
lowing 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 stabilise the vehi-
cle if the vehicle starts to skid or a wheel
starts to spin.
Deactivating/activating ESP ®
You can deactivate or activate ESP ®
via the
on-board computer.
X To deactivate:(Y page 218).
The å ESP®
OFF warning lamp in the
instrument cluster lights up.
X To activate:( Ypage 218).
The å ESP®
OFF warning lamp in the
instrument cluster goes out.
Characteristics when ESP ®
is deactivated
If ESP ®
is deactivated and one or more wheels
start to spin, the ÷ESP®
warning lamp in
the instrument cluster flashes. In such situa-
tions, ESP ®
will not stabilise the vehicle.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R engine torque is no longer limited and the
drive wheels are able to spin.
The spinning of the wheels results in a cut-
ting action for better traction on loose sur- faces.
R traction control is still activated.
R ESP ®
still provides support when you
brake. ESP
®
trailer stabilisation General notes
If your vehicle/trailer combination begins to
lurch, ESP
®
assists you in this situation. ESP ®
slows the vehicle down by braking and limit-
ing the engine output until the vehicle/trailer combination has stabilised.
Important safety notes G
WARNING
If road and weather conditions are poor,
trailer stabilisation will not be able to prevent the vehicle/trailer combination from swerv-
ing. Trailers with a high centre of gravity can
tip over before ESP ®
can detect this. There is
a risk of an accident.
Always adapt your driving style to the prevail-
ing road and weather conditions.
If your vehicle/trailer combination begins to
lurch, you can only stabilise the vehicle/
trailer combination by depressing the brake
firmly.
ESP ®
trailer stabilisation is active above
speeds of about 65 km/h.
ESP ®
trailer stabilisation does not work if
ESP ®
is deactivated or disabled because of a
malfunction. EBD (electronic brake force distribu-
tion)
i Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 61). G
WARNING
If EBD has malfunctioned, the rear wheels can still lock, e.g. under full braking. This increa-
ses the risk of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Havethe brake system checked at a qualified spe-
cialist workshop. 68
Driving safety systemsSafety

Problem
Possible causes/consequences and
M
MSolutions The engine cannot be
started using the key. The on-board voltage is too low.
X Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 304).
or
X Jump-start the vehicle (Y page 308).
or
X Consult a qualified specialist workshop. The engine cannot be
started using the key. The steering lock is mechanically blocked.
X Remove the key and reinsert it into the ignition lock. While doing
this, turn the steering wheel in both directions. Doors
Important safety notes
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 shift the manual transmission into neutral.
R start the engine.
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 or animals unattended in the vehicle.Always keep the key out of reach of children. 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.
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,
then the double lock function is activated as
standard. You can deactivate the double lock
function by deactivating the interior motion
sensor (Y page 70). The doors can then be
opened from the inside after the vehicle has
been locked from the outside. The anti-theft Doors
79Opening and closing Z