brakes MERCEDES-BENZ A CLASS 2012 User Guide

A
Neutral
No power is transmitted from the
engine to the drive wheels.
Releasing
the brakes will allow you
to move the vehicle freely, e.g. to
push it or tow it.
If ESP ®
is deactivated or faulty:
only shift the transmission to posi-
tion N if the vehicle is in danger of
skidding, e.g. on icy roads.
When you switch off the engine, the
automatic transmission automati-
cally shifts into neutral N.7
Drive
The automatic transmission
changes gear automatically. All
forward gears are available.
Changing gear
The
automatic transmission shifts to the indi-
vidual gears automatically when it is in trans-
mission position D. Gearshifting is deter-
mined by:
R the selected drive program ( Y page 155)
R the position of the accelerator pedal
R the road speed Driving tips
Accelerator pedal position Your style of driving influences how the auto-
matic transmission shifts gear:
R
little throttle: early upshifts
R more throttle: late upshifts
Holding

the vehicle stationary on uphill
gradients G
WARNING
If the clutch overheats, the electronic man-
agement
system is automatically deactivated. This interrupts the power transmission. The
vehicle may, for example, roll backwards on
gradients. There is a risk of an accident.
Never hold the vehicle stationary on uphill
gradients by depressing the accelerator.
The

clutch may overheat if you hold the vehi-
cle stationary on uphill gradients by depress-
ing the accelerator pedal. If the clutch over-
heats, a warning tone sounds.
All vehicles (except AMG vehicles): the
Stop vehicle Shift to P Leave engine
running display message appears in the mul-
tifunction display. You will only be able to
continue your journey once the clutch has
cooled down and the display message in the
multifunction display has disappeared.
AMG vehicles: the Trans. oil overhea‐
ted Drive on with care display message
appears in the multifunction display.
Do not hold the vehicle stationary on uphill
gradients by depressing the accelerator
pedal. Instead, only ever hold the vehicle sta-
tionary on uphill gradients by:
R depressing the brake pedal
R activating the HOLD function
R engaging the electric parking brake
Kickdown AMG vehicles:
it
is only possible to use kick-
down in temporary manual drive program M.
For further information on the manual drive
program M, see ( Y page 156).
Use kickdown for maximum acceleration:
X Depress the accelerator pedal beyond the
pressure point.
The transmission shifts to a lower gear
depending on the engine speed.
X Ease off the accelerator pedal once the
desired speed is reached.
The

automatic transmission shifts back up.154
Automatic transmission
Driving and parking

Driving tips
General notes
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. ECO display
The ECO display provides feedback on how
economical your driving characteristics are.
The ECO display assists you in achieving the
most economical driving style for the selec-
ted settings and prevailing conditions. Con-
sumption can be significantly influenced by
your driving style. Example: ECO display
The ECO display consists of three bars:
R
Acceleration
R Constant
R Coasting
The

percentage count is the mean value of the
three bar values. The three bars and the mean
value begin at the value of 50%. A higher per-
centage count indicates a more economical
driving style.
The ECO display does not indicate the actual
fuel consumption and a fixed percentage
count in the ECO display does not indicate a
fixed consumption figure. In addition to driving style, the consumption
is affected by many other factors, such as:
R
load
R tyre pressure
R cold start
R choice of route
R the use of electrical consumers
These

factors are not included in the ECO dis-
play.
The evaluation of your driving style takes the
following three categories into consideration:
R Acceleration (evaluation of all accelera-
tion processes):
-The bar fills up: moderate acceleration,
especially at higher speeds
- The bar empties: sporty acceleration
R Constant (assessment of driving behav-
iour at all times):
-The bar fills up: constant speed and
avoidance of unnecessary acceleration
and deceleration
- The bar empties: fluctuations in speed
R Coasting (assessment of all deceleration
processes):
-The bar fills up: anticipatory driving,
keeping your distance and early release
of the accelerator. The vehicle can coast
without use of the brakes
- The bar empties: frequent braking
i An economical driving style involves driv-
ing at a moderate engine speed.
To achieve a higher value in the categories
Acceleration and Constant:
R observe the gearshift recommendation.
R drive the vehicle in drive program E (vehi-
cles with automatic transmission).
i On long journeys at a constant speed, e.g.
on the motorway, only the bar for Con‐
stant will change.
i The ECO display summarises the driving
characteristics from the start of the journey
to its completion. Therefore, there are Driving tips
165
Driving and parking Z

dynamic changes in the bars at the start of
a
journey. During a prolonged driving time,
these changes are smaller. For more
dynamic changes, perform a manual reset.
For further information on the ECO display,
see ( Y page 212). Braking
Important safety notes G
WARNING
If you shift down on a slippery road surface in
an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
This

increases the risk of skidding and having
an accident.
Do not shift down for additional engine brak-
ing on a slippery road surface.
Downhill gradients Change into a lower gear in good time on long
and

steep downhill gradients. Take particular
note of this when driving a laden vehicle and
when towing a trailer. For vehicles with auto-
matic transmission, you need to have selec-
ted manual drive program M(Y page 156).
i This also applies if you have activated
cruise control, SPEEDTRONIC or DIS-
TRONIC PLUS.
This will use the braking effect of the engine,
so less braking will be required to prevent the
vehicle from gaining speed. This relieves the
load on the brake system and prevents the
brakes from overheating and wearing too
quickly.
i Briefly depressing the accelerator pedal
on downhill gradients while the manual
drive program M is temporarily activated
(vehicles with automatic transmission): the
automatic transmission may switch back to
the last active automatic drive program E
or S. The automatic transmission may shift to a higher gear. This can reduce the
engine's braking effect.
Heavy and light loads G
WARNING
The braking system can overheat if you leave
your foot on the brake pedal while driving.
This

increases the braking distance and could
even cause the braking system to fail. There
is a risk of an accident.
Never use the brake pedal as a footrest. Do
not simultaneously depress both the brake
pedal and the accelerator pedal while driving.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If heavy demands are made on the brakes, do
not park the vehicle immediately. Drive on for
a short while. This allows the airflow to cool
the brakes more quickly.
If the brakes have been used only moderately,
you should occasionally test their effective-
ness. To do this, brake more firmly from a
higher speed, paying attention to traffic con-
ditions. This improves the grip of the brakes.
Wet road surfaces If you have driven for a long time in heavy rain
without

braking, there may be a delayed reac-
tion from the brakes when braking for the first
time. This may also occur after a car wash or
after driving through deep water.
You have to depress the brake pedal more
firmly. Maintain a greater distance from the
vehicle in front.
After driving on a wet road or having the vehi-
cle washed, brake firmly while paying atten-
tion to the traffic conditions. This will warm
up the brake discs, thereby drying them more
quickly and protecting them against corro-
sion. 166
Driving tips
Driving and parking

Have your vehicle winterproofed at a qualified
specialist workshop at the onset of winter.
Observe the notes in the "Winter operation"
section (
Y page 320).
Driving with summer tyres Observe the notes in the "Winter operation"
section (
Y page 320).
Slippery road surfaces G
WARNING
If you shift down on a slippery road surface in
an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
This
increases the risk of skidding and having
an accident.
Do not shift down for additional engine brak-
ing on a slippery road surface.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
X Vehicles with manual transmission:
shift to neutral.
X Vehicles with automatic transmission:
shift the transmission to position N.
X Try to bring the vehicle under control by
using corrective steering.
You should drive particularly carefully on slip-
pery road surfaces. Avoid sudden accelera-
tion, steering and braking manoeuvres.
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Changes in the outside temperature are dis-
played after a short delay.
Indicated temperatures just above the freez-
ing point do not guarantee that the road sur-
face is free of ice. The road may still be icy,
especially

in wooded areas or on bridges. You
should pay special attention to road condi-
tions when temperatures are around freezing
point.
i For more information on driving with
snow chains, see ( Y page 321). Driving systems
Cruise control
Important safety notes If you fail to adapt your driving style, cruise
control

can neither reduce the risk of an acci-
dent nor override the laws of physics. Cruise
control cannot take into account road,
weather or traffic conditions. Cruise control
is only an aid. You are responsible for the dis-
tance to the vehicle in front, for vehicle speed,
for braking in good time, and for staying in the
lane.
Do not use cruise control:
R in road and traffic conditions which do not
allow you to maintain a constant speed
(e.g. in heavy traffic or on winding roads).
R on smooth or slippery roads. Braking or
accelerating can cause the drive wheels to
lose traction and the vehicle could then
skid.
R when there is poor visibility, e.g. due to fog,
heavy rain or snow.
If there is a change of drivers, advise the new
driver of the speed stored.
General notes Cruise control maintains a constant road
speed

for you. It brakes automatically in order
to avoid exceeding the set speed. You must
select a lower gear in good time on long and
steep downhill gradients, especially if the
vehicle is laden or towing a trailer. For vehi-
cles with automatic transmission, you need
to have selected manual drive program
M(Y page 156). By doing so, you will make
use of the braking effect of the engine. This
relieves the load on the brake system and
prevents the brakes from overheating and
wearing too quickly.
Use cruise control only if road and traffic con-
ditions make it appropriate to maintain a
steady speed for a prolonged period. You can
store any road speed above 30 km/h. 168
Driving systems
Driving and parking

Storing the current speed and calling up
the last stored speed
G
WARNING
If you call up a stored speed and this is dif-
ferent from the current speed, the vehicle
accelerates or brakes. If you do not know
what the stored speed is, the vehicle may
accelerate or brake unexpectedly. There is a
risk of an accident.
Take the traffic conditions into account
before calling up the stored speed. If you do
not know what the stored speed is, store the
desired speed again.
X Briefly pull the cruise control lever towards
you =.
X Remove your foot from the accelerator
pedal.
The first time cruise control is activated, it
stores the current speed or regulates the
speed of the vehicle to the previously
stored speed.
Setting a speed Keep in mind that it may take a brief moment
until
the vehicle has accelerated or braked to
the set speed.
X Press the cruise control lever up : for a
higher

speed or down ? for a lower speed.
X Keep the cruise control lever pressed until
the desired speed is reached.
X Release the cruise control lever.
The new speed is stored.
X To adjust the set speed in 1 km/h incre-
ments: briefly press the cruise control
lever up : or down ? to the pressure
point.
The

last stored speed increases or decrea-
ses in 1 km/h increments.
X To adjust the set speed in 10 km/h
increments:

press the cruise control lever
briefly up : or down ? beyond the pres-
sure point.
The last stored speed increases or decrea-
ses in 10 km/h increments. i
Cruise control is not deactivated if you
depress the accelerator pedal. For exam-
ple, if you accelerate briefly to overtake,
cruise control adjusts the vehicle's speed
to

the last speed stored after you have fin-
ished overtaking.
Deactivating cruise control There are several ways to deactivate cruise
control:
X
Briefly press the cruise control lever for-
wards B.
or
X Brake
or
X Briefly press the cruise control lever in the
direction of arrow A.
Variable SPEEDTRONIC is selected. LIM
indicator

lamp ; in the cruise control lever
lights up.
Cruise control is automatically deactivated if:
R you engage the electric parking brake.
R you are driving at less than

30 km/h.
R ESP ®
intervenes or you deactivate ESP ®
R while driving a vehicle with manual trans-
mission, you shift into neutral or depress
the clutch pedal for longer than six sec-
onds.
R on vehicles with manual transmission, you
shift to a gear that is too high, and as a
result the engine speed is too low.
R on vehicles with automatic transmission,
you shift into position N while driving.
If cruise control is deactivated, you will hear
a warning tone. You will see the Cruise
control off message in the multifunction
display for approximately five seconds.
i The last speed stored is cleared when you
switch off the engine. 170
Driving systems
Driving and parking

SPEEDTRONIC
Important safety notes SPEEDTRONIC brakes automatically so that
you
do not exceed the set speed. On long and
steep downhill gradients, especially if the
vehicle is laden or towing a trailer, you must
select shift range 1, 2 or 3 in good time. By
doing so, you will make use of the braking
effect of the engine. This relieves the load on
the brake system and prevents the brakes
from overheating and wearing too quickly. If
you need additional braking, depress the
brake pedal repeatedly rather than continu-
ously.
If you fail to adapt your driving style, SPEED-
TRONIC can neither reduce the risk of an
accident nor override the laws of physics.
SPEEDTRONIC cannot take into account
road, weather or traffic conditions. SPEED-
TRONIC is only an aid. You are responsible for
the distance to the vehicle in front, for vehicle
speed, for braking in good time, and for stay-
ing in the lane.
If there is a change of drivers, advise the new
driver of the speed stored.
General notes You can set a variable or permanent limit
speed:
R
variable for speed limits, e.g. in built-up
areas
R permanent for long-term speed restric-
tions, e.g. when driving with winter tyres
fitted (Y page 172)
i The speed indicated in the speedometer
may differ slightly from the limit speed
stored.
Variable SPEEDTRONIC General notes
With

the cruise control lever, you can operate
cruise control or DISTRONIC PLUS and vari-
able SPEEDTRONIC. The LIM indicator lamp on the cruise control
lever

indicates which system you have selec-
ted:
R LIM indicator lamp off: cruise control or
DISTRONIC PLUS is selected.
R LIM indicator lamp on: variable SPEED-
TRONIC is selected.
You can use the cruise control lever to limit
the speed to any speed above 30 km/h while
the engine is running. :
To store the current speed or a higher
speed
; LIM indicator lamp
= To store the current speed and calling up
the last stored speed
? To store the current speed or a lower
speed
A To switch between cruise control or DIS-
TRONIC

PLUS and variable SPEEDTRONIC
B To deactivate variable SPEEDTRONIC
Selecting variable SPEEDTRONIC
X Check whether LIM indicator lamp ;
is on.
If it is on, variable SPEEDTRONIC is already
selected.
If it is not, press the cruise control lever in
the direction of arrow A.
LIM indicator lamp ; in the cruise control
lever lights up. Variable SPEEDTRONIC is
selected.
X Make sure that the accelerator pedal is not
depressed beyond the pressure point. Driving systems
171
Driving and parking Z

Shortly before the stored speed is reached, it
appears in the multifunction display.
Permanent SPEEDTRONIC remains active,
even
if variable SPEEDTRONIC is deactivated.
You cannot exceed the stored limit speed,
even if you depress the accelerator pedal
beyond the pressure point (kickdown). DISTRONIC PLUS
Important safety notes G
WARNING
DISTRONIC PLUS does not react to:
R people or animals
R stationary

obstacles on the road, e.g. stop-
ped or parked vehicles
R oncoming and crossing traffic
As a result, DISTRONIC PLUS may neither give
warnings nor intervene in such situations.
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake. G
WARNING
DISTRONIC PLUS cannot always clearly iden-
tify other road users and complex traffic sit-
uations.
In such cases, DISTRONIC PLUS may:
R give an unnecessary warning and then
brake the vehicle
R neither give a warning nor intervene
R accelerate unexpectedly
There is a risk of an accident.
Continue to drive carefully and be ready to
brake, in particular when warned to do so by
DISTRONIC PLUS. G
WARNING
DISTRONIC PLUS brakes your vehicle with up
to 40% of the maximum braking force. If this
braking

force is insufficient, DISTRONIC PLUS
warns you visually and audibly. There is a risk
of an accident. In such cases, apply the brakes yourself and
try to take evasive action.
! If

DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes automati-
cally in certain situations. To prevent dam-
age to the vehicle, deactivate DISTRONIC
PLUS and the HOLD function in the follow-
ing or other similar situations:
R when towing the vehicle
R in the car wash
If you fail to adapt your driving style, DIS-
TRONIC PLUS can neither reduce the risk of
an accident nor override the laws of physics.
DISTRONIC PLUS cannot take road and
weather conditions or traffic conditions into
account. DISTRONIC PLUS is only an aid. You
are responsible for the distance to the vehicle
in front, for vehicle speed, for braking in good
time, and for staying in the lane.
Do not use DISTRONIC PLUS:
R in road and traffic conditions which do not
allow you to maintain a constant speed
(e.g. in heavy traffic or on winding roads).
R on smooth or slippery roads. Braking or
accelerating can cause the drive wheels to
lose traction and the vehicle could then
skid.
R when there is poor visibility, e.g. due to fog,
heavy rain or snow.
DISTRONIC PLUS may not detect narrow
vehicles driving in front, e.g. motorcycles, or
vehicles driving on a different line.
In particular, the detection of obstacles can
be impaired by:
R dirt on the sensors or anything else cover-
ing the sensors
R snow or heavy rain
R interference by other radar sources
R the possibility of strong radar reflections,
for example, in multi-storey car parks
If DISTRONIC PLUS no longer detects a vehi-
cle in front, it may unexpectedly accelerate to
the speed stored. Driving systems
173
Driving and parking Z

This speed can:
R
be too high for a filter lane or a slip road
R be so high in the right lane that you pass
vehicles driving on the left
R be so high in the left lane that you pass
vehicles driving on the right
If
there is a change of drivers, advise the new
driver of the speed stored.
General notes DISTRONIC PLUS regulates the speed and
automatically helps you maintain the dis-
tance to the vehicle detected in front. DIS-
TRONIC PLUS brakes automatically so that
the set speed is not exceeded.
You

must select a lower gear in good time on
long and steep downhill gradients, especially
if the vehicle is laden or towing a trailer. For
this, you need to have selected manual drive
program M(Y page 166). By doing so, you will
make use of the braking effect of the engine.
This relieves the load on the brake system and
prevents the brakes from overheating and
wearing too quickly.
If a slower-moving vehicle is detected in front,
DISTRONIC PLUS brakes your vehicle. It
maintains the preset distance to the vehicle
in front.
If DISTRONIC PLUS detects that there is a risk
of a collision, you will be warned visually and
acoustically. Without your intervention, DIS-
TRONIC PLUS cannot prevent a collision. An
intermittent warning tone will then sound and
the distance warning lamp will light up in the
instrument cluster. Brake immediately to
increase the distance to the vehicle driving in
front, or take evasive action, provided it is
safe to do so.
The radar sensor system is switched off auto-
matically in the vicinity of radio telescope
facilities ( Y page 350).
For DISTRONIC PLUS to assist you when driv-
ing, the radar sensor system must be:
R activated (Y page 223)
R operational i
In some countries you must deactivate
the radar sensor system ( Y page 223).
For

further information about the radar sen-
sor system; see ( Y page 350).
DISTRONIC PLUS is automatically deactiva-
ted if:
R you are driving slower than 25 km/h and
there is no longer a vehicle in front or
R the vehicle ahead has not been detected
If there is no vehicle in front, DISTRONIC
PLUS operates in the same way as cruise
control in the speed range between
30 km/h and 200 km/h. If a vehicle is driving
in front of you, it operates in the speed range
between 0 km/h and 200 km/h.
Do not use DISTRONIC PLUS on roads with
steep gradients.
Cruise control lever With the cruise control lever, you can operate
DISTRONIC PLUS and variable SPEED-
TRONIC.
The LIM indicator lamp on the cruise control
lever

indicates which system you have selec-
ted:
R LIM indicator lamp off: DISTRONIC PLUS
is selected.
R LIM indicator lamp on: variable SPEED-
TRONIC is selected. :
To store the current speed or a higher
speed
; To set the specified minimum distance
= LIM indicator lamp174
Driving systems
Driving and parking

When DISTRONIC PLUS is activated, one or
two
segments ; in the set speed range light
up.
i For design reasons, the speed displayed
in the speedometer may differ slightly from
the speed set for DISTRONIC PLUS.
If DISTRONIC PLUS detects a vehicle in front,
segments ; between speed of the vehicle in
front : and stored speed = light up.Assistance graphic in vehicles with a colour multi-
function display
:
Vehicle in front, if detected
; Specified minimum distance to the vehi-
cle in front; adjustable
= Own vehicle
? DISTRONIC PLUS active (text only
appears when the cruise control lever is
actuated)
In the Assistance menu (Y page 217) of the
on-board
computer, you can select the assis-
tance graphic.
X Select the Distance display function
using the on-board computer
(Y page 217).
i You
will see the stored speed for approx-
imately five seconds when you activate
DISTRONIC PLUS.
Activating at the current speed/last
stored speed G
WARNING
If you call up a stored speed and this is dif-
ferent from the current speed, the vehicle
accelerates or brakes. If you do not know what the stored speed is, the vehicle may
accelerate or brake unexpectedly. There is a
risk of an accident.
Take the traffic conditions into account
before calling up the stored speed. If you do
not know what the stored speed is, store the
desired speed again.
X Briefly pull the cruise control lever
(Y page 174) towards you ?.
X Remove your foot from the accelerator
pedal.
DISTRONIC PLUS is activated. The first
time it is activated, the current speed is
stored.

Otherwise, it sets the vehicle cruise
speed to the previously stored value.
Setting a speed Keep in mind that it may take a brief moment
until

the vehicle has accelerated or braked to
the set speed. :
To store the current speed or a higher
speed
; To store the current speed or a lower
speed
X Press the cruise control lever up : for a
higher

speed or down ; for a lower speed.
X Keep the cruise control lever pressed until
the desired speed is reached.
X Release the cruise control lever.
The

new speed is stored. DISTRONIC PLUS
is activated and adjusts the vehicle's speed
to the new speed stored. 176
Driving systems
Driving and parking

!
If DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes automati-
cally in certain situations. To prevent dam-
age to the vehicle, deactivate DISTRONIC
PLUS and the HOLD function in the follow-
ing or other similar situations:
R when towing the vehicle
R in the car wash
Deactivate the HOLD function (Y page 180).
General notes The HOLD function can assist the driver in the
following situations:
R
when pulling away, especially on steep
slopes
R when manoeuvring on steep slopes
R when waiting in traffic
The vehicle is kept stationary without the
driver having to depress the brake pedal.
The

braking effect is cancelled and the HOLD
function is deactivated when you depress the
accelerator pedal to pull away.
Activation conditions You can activate the HOLD function if:
R
the vehicle is stationary
R the

engine is running or if it has been auto-
matically switched off by the ECO start/
stop function
R the driver's door is closed or if your seat
belt is fastened
R the electric parking brake is released
R the transmission is in position D, R or N on
vehicles with automatic transmission
R DISTRONIC PLUS is deactivated Activating the HOLD function Example: vehicles with colour multifunction display
X
Make sure that the activation conditions
are met.
X Depress the brake pedal.
X Quickly depress the brake pedal further
until : appears in the multifunction dis-
play.
The HOLD function is activated. You can
release the brake pedal.
i If depressing the brake pedal the first
time does not activate the HOLD function,
wait briefly and then try again.
Deactivating the HOLD function The HOLD function is deactivated automati-
cally if:
R
you

accelerate. On vehicles with automatic
transmission: only when the transmission
is in position D or R.
R the transmission is in position P on vehicles
with automatic transmission.
R you depress the brake pedal again with a
certain amount of pressure until : disap-
pears from the multifunction display.
R you secure the vehicle using the electric
parking brake.
R you activate DISTRONIC PLUS.
i After a short period the vehicle is secured
by the electric parking brake, thus relieving
the service brake. 180
Driving systems
Driving and parking