MERCEDES-BENZ A CLASS 2012 Owners Manual
Page 181 of 356
Other vehicles changing lane
DISTRONIC PLUS has not detected the vehi-
cle
cutting in yet. The distance to this vehicle
will be too short.
Narrow vehicles DISTRONIC PLUS has not yet detected the
vehicle in front on the edge of the carriage-
way, because of its narrow width. The dis-
tance
to the vehicle in front will be too short.
Obstructions and stationary vehicles DISTRONIC PLUS does not brake for obsta-
cles
or stationary vehicles. If, for example, the detected vehicle turns a corner and reveals
an
obstacle or stationary vehicle, DISTRONIC
PLUS will not brake for these.
Crossing vehicles DISTRONIC PLUS may detect vehicles that
are
crossing your lane by mistake. Activating
DISTRONIC PLUS at traffic lights with cross-
ing traffic, for example, could cause your vehi-
cle to pull away unintentionally. HOLD function
Important safety notes G
WARNING
When leaving the vehicle, it can still roll away
despite
being braked by the HOLD function if:
R there is a malfunction in the system or in
the voltage supply
R the HOLD function is deactivated by the
accelerator pedal being depressed, e.g. by
a vehicle occupant
R the electrical system in the engine com-
partment, the battery or the fuses are tam-
pered with
R the battery is disconnected
There is a risk of an accident.
Before leaving the vehicle, always deactivate
the HOLD function and secure the vehicle
from rolling away. Driving systems
179
Driving and parking Z
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!
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
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The electric parking brake secures the vehicle
automatically if the HOLD function is activa-
ted and:
R
the driver's door is open and the driver's
seat belt is unfastened
R the
engine is switched off, unless it is auto-
matically switched off by the ECO start/
stop function
R a system fault occurs
R the power supply is not sufficient
Vehicles with automatic transmission
If a fault occurs, then the transmission may
also be shifted into position P automatically.
Vehicles with manual transmission
The Brake immediately message can also
appear in the multifunction display.
X Immediately depress the brake pedal firmly
until
the warning message in the multifunc-
tion display goes out.
The HOLD function is deactivated.
A horn will sound at regular intervals if you
turn off the engine, take off your seat belt or
open the driver's door when the HOLD func-
tion is activated. The horn alerts you to the
fact that the HOLD function is still activated.
If you attempt to lock the vehicle, the tone
becomes louder. The vehicle cannot be
locked until you have deactivated the HOLD
function.
i Once you have switched off the engine,
you cannot restart it until you have deacti-
vated the HOLD function. RACE START
Important safety notes RACE START enables optimum acceleration
from a standing start. The precondition for
this is a suitable high-grip road surface.
Only
activate RACE START on dedicated race
circuits. i
RACE
START is only available in AMG vehi-
cles.
Activation conditions You can activate RACE START if:
R
the doors, the bonnet and the tailgate are
closed
R the
engine is running and the transmission,
traction control and engine are at operating
temperature
R SPORT handling mode is activated
(Y page 66)
R the steering wheel is in the straight-ahead
position.
R the vehicle is stationary and the brake
pedal is depressed (left foot)
R the transmission is in position D.
R drive program M is selected ( Y page 155).
Activating RACE START X
Depress the brake pedal with your left foot
and keep it depressed.
X Pull and hold both steering wheel gearshift
paddles.
X The RACE START Confirm: Paddle UP
Cancel: Paddle DOWN message appears
in the multifunction display.
X Release both steering wheel gearshift pad-
dles.
i If the activation conditions are no longer
fulfilled, RACE START is cancelled. The
RACE START not possible See Own‐
er's
Manual message appears in the mul-
tifunction display.
X To cancel:
pull the left steering wheel shift
paddle (Y page 156).
or
X To confirm: pull the right steering wheel
shift paddle
(Y page 156).
The RACE START available Depress
accelerator message appears in the mul-
tifunction display. Driving systems
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i
If you do not depress the accelerator
pedal
within a few seconds, RACE START is
cancelled. The multifunction display shows
the RACE START cancelled message.
X Fully depress the accelerator pedal.
The engine speed is increased.
The RACE START Release brake to
start message appears in the multifunc-
tion display.
i If the brake pedal is not released after a
short while, RACE START is cancelled. The
multifunction display shows the RACE
START cancelled message.
X Take your foot off the brake, but keep the
accelerator pedal depressed.
The vehicle pulls away at maximum accel-
eration.
The RACE
START active message appears
in the multifunction display.
RACE START is deactivated when the vehicle
reaches a speed of approximately
50 km/h.
Drive program S is activated. SPORT handling
mode remains activated.
RACE START is deactivated immediately if
you release the accelerator pedal during
RACE START or if any of the activation condi-
tions are no longer fulfilled. The RACE START
not possible or RACE START cancelled
message appears in the multifunction dis-
play.
i After using it several times in short suc-
cession, RACE START will be unavailable
until a certain distance has been driven. 4MATIC (permanent all-wheel drive)
4MATIC ensures that all four wheels are per-
manently driven. Together with ESP ®
, it
improves the traction of your vehicle when-
ever a drive wheel spins due to insufficient
grip.
If
you fail to adapt your driving style, 4MATIC
can neither reduce the risk of accident nor
override the laws of physics. 4MATIC cannot take account of road, weather and traffic con-
ditions. 4MATIC 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.
If
a drive wheel spins due to insufficient grip:
R when pulling away, only depress the accel-
erator pedal as far as is necessary.
R accelerate less when driving.
! Never tow the vehicle with one axle
raised. This may damage the transfer case.
Damage of this sort is not covered by the
Mercedes-Benz implied warranty. All
wheels must remain either on the ground
or be fully raised. Observe the instructions
for towing the vehicle with all wheels in full
contact with the ground.
i In wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if
you use winter tyres (M+S tyres), with snow
chains if necessary. PARKTRONIC
Important safety notes PARKTRONIC is only an aid. It is not a substi-
tute for your attention to the immediate sur-
roundings. The responsibility for safe
manoeuvring and parking remains with you.
Make
sure that there are no persons, animals
or objects in range while manoeuvring and
parking.
! When parking, pay particular attention to
objects above or below the sensors, such
as flower pots or trailer drawbars. PARK-
TRONIC does not detect such objects when
they are in the immediate vicinity of the
vehicle. You could damage the vehicle or
the objects.
The sensors may not detect snow and
objects which absorb ultrasonic sources.
Ultrasonic sources, such as an automatic
car wash, a lorry's compressed-air brakes 182
Driving systems
Driving and parking
Page 185 of 356
or a pneumatic drill, could cause PARK-
TRONIC to malfunction.
PARKTRONIC
may not function correctly on
uneven terrain.
PARKTRONIC is an electronic parking aid with
ultrasonic sensors. It indicates visually and
audibly the distance between your vehicle
and an object.
PARKTRONIC is activated automatically if
you:
R switch on the ignition
R shift to position D, R or N on vehicles with
automatic transmission
R release the electric parking brake
PARKTRONIC is deactivated at speeds above
18 km/h. It is reactivated at lower speeds.
PARKTRONIC monitors the area around your
vehicle using six sensors in the front bumper
and four sensors in the rear bumper.
Range of the sensors General notes
PARKTRONIC does not take into account
obstacles located:
R
below the detection range, e.g. persons,
animals or objects
R above the detection range, e.g. overhang-
ing loads, tail sections or loading ramps of
goods vehicles :
Example: sensors in the front bumper,
left-hand side Side view
Top view
The sensors must be free of dirt, ice and
slush. Otherwise, they may not function cor-
rectly. Clean the sensors regularly, taking
care not to scratch or damage them
(Y page 294).
Front sensors
Centre Approx. 100 cm
Corners Approx. 60 cm
Rear sensors
Centre Approx. 120 cm
Corners Approx. 80 cm
Minimum distance
Centre Approx. 20 cm
Corners Approx. 20 cm
If there is an obstacle within this range, the
relevant
warning displays light up and a warn-
ing tone sounds. If the distance falls below
the minimum, the distance may no longer be
shown. Driving systems
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Driving and parking Z
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Warning displays
The warning displays show the distance
between the sensors and the obstacle. The
warning display for the front area is located
on
the dashboard above the centre air vents.
The warning display for the rear area is loca-
ted on the roof lining in the rear compart-
ment. Warning display for the front area
:
Segments on the left-hand side of the
vehicle
; Segments on the right-hand side of the
vehicle
= Segments showing operational readiness
The warning display for each side of the vehi-
cle
is divided into five yellow and two red seg-
ments. PARKTRONIC is operational if yellow
segments showing operational readiness =
light up.
The gear lever position or the transmission
position of the automatic transmission and
the direction in which the vehicle is rolling
determine which warning display is active
when the engine is running. Manual transmission: Gear lever posi-
tion Warning display
Forwards gear
or
Neutral
Front area activated
Reverse gear, or
the
vehicle is rolling
backwards Rear and front areas
activated
Automatic transmission:
Transmission
position Warning display
D
Front area activated
R, N or the vehicle
is rolling back-
wards Rear and front areas
activated
P
No areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the
vehicle's distance from the obstacle.
From the:
R
sixth segment onwards, you will hear an
intermittent warning tone for approx-
imately two seconds.
R seventh segment onwards, you will hear a
warning tone for approximately two sec-
onds. This indicates that you have now
reached the minimum distance.184
Driving systems
Driving and parking
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Deactivating/activating PARKTRONIC
:
Indicator lamp
; To deactivate/activate PARKTRONIC
If indicator lamp : lights up, PARKTRONIC is
deactivated.
i PARKTRONIC is automatically activated
when you turn the key to position 2 in the
ignition lock.
Towing a trailer !
Fold in the ball coupling if the trailer tow
hitch is not required. PARKTRONIC meas-
ures the minimum detection range to an
obstacle
from the bumper, not the ball cou-
pling.
PARKTRONIC is deactivated for the rear area
when you establish an electrical connection
between your vehicle and a trailer. Driving systems
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Problems with PARKTRONIC
Problem Possible causes/consequences and
M SolutionsOnly the red segments
in the PARKTRONIC
warning
displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is deacti-
vated after approx-
imately five seconds,
and the indicator lamp
in the PARKTRONIC
button lights up. PARKTRONIC has malfunctioned and has switched off.
X
If problems persist, have PARKTRONIC checked at a qualified
specialist workshop. Only the red segments
in the PARKTRONIC
warning
displays are lit.
PARKTRONIC is deacti-
vated after approx-
imately five seconds. The PARKTRONIC sensors are dirty or there is interference.
X
Clean the PARKTRONIC sensors ( Y page 294).
X Switch the ignition back on. The problem may be caused by an external source of radio or
ultrasound waves.
X
See if PARKTRONIC functions in a different location. Active Parking Assist
Important safety notes Active Parking Assist is only an aid. It is not a
substitute
for your attention to the immediate
surroundings. The responsibility for safe
manoeuvring and parking remains with you.
Make sure that there are no persons, animals
or objects in range while manoeuvring and
parking. G
WARNING
The vehicle will veer out when parking and can
take
you onto sections of the oncoming lane.
As a result, you may collide with other road
users. There is a risk of an accident.
When parking, pay attention to other road
users. Stop the vehicle if necessary or cancel
the Active Parking Assist parking procedure.
! If unavoidable, you should drive over
obstacles such as kerbs slowly and not at a sharp angle. Otherwise, you may damage
the wheels or tyres.
Active
Parking Assist may also display spaces
not suitable for parking, e.g.:
R parking or stopping prohibitions
R in front of driveways or entrances and exits
R unsuitable surfaces
Parking tips:
R on narrow roads, drive as closely as possi-
ble past the parking space.
R parking spaces that are littered, overgrown
or partially occupied by trailer drawbars
might be identified incorrectly or not at all.
R snowfall or heavy rain may lead to a parking
space being measured inaccurately.
R pay attention to the PARKTRONIC
(Y page 184) warning messages during the
parking procedure. 186
Driving systems
Driving and parking
Page 189 of 356
R
at any time, you can intervene in the steer-
ing procedure to correct it. Active Parking
Assist will then be cancelled.
R when transporting a load which protrudes
from your vehicle, you should not use
Active Parking Assist.
R never use Active Parking Assist when snow
chains are fitted.
R make sure that the tyre pressures are
always correct. This has a direct influence
on the parking characteristics of the vehi-
cle.
General notes Active Parking Assist is an electronic parking
aid with ultrasound. Ultrasound is used to
measure
the road on both sides of the vehicle.
A suitable parking space is indicated by the
parking symbol. Active steering intervention
can assist you during parking.
You may also use PARKTRONIC
(Y page 182). When PARKTRONIC is switched
off, Active Parking Assist is also unavailable.
Use Active Parking Assist for parking spaces:
R that are parallel to the direction of travel
R that are on straight roads, not bends
R that are on the same level as the road, e.g.
not on the pavement
Detecting parking spaces Objects located above the height range of
Active Parking Assist will not be detected
when the parking space is measured. These
are not taken into account when the parking
procedure is calculated, e.g. overhanging
loads,
tail sections or loading ramps of goods
vehicles. G
WARNING
If objects are located above the detection
range,
Active Parking Assist may start to steer
into the parking space too soon. As a result,
you could cause a collision. There is a risk of
an accident. If objects are located above the detection
range, stop the vehicle and switch Active
Parking Assist off.
For further information on the detection
range (Y page 183).
Active Parking Assist does not support you
parking in spaces that are parallel to the
direction of travel if:
R the parking space is on a kerb stone
R the parking space appears to be blocked,
for example by foliage or grass paving
blocks
R the range of movement is too small
R the
parking space is bordered by an obsta-
cle which is not clearly defined such as a
tree or a trailer :
Detected parking space on the left
; Parking symbol
= Detected parking space on the right
Active Parking Assist is activated automati-
cally when driving forwards. The system is
operational
at speeds of up to approximately
35 km/h. While in operation, the system inde-
pendently locates and measures parking
spaces on both sides of the vehicle.
Active Parking Assist will only detect parking
spaces:
R that are parallel to the direction of travel
R that are at least 1.5 m wide
R that are at least 1.3 m longer than your
vehicle
i In the case of parking spaces that are at
right angles to the direction of travel,
please ensure that the parking space is
long enough to accommodate your vehicle. Driving systems
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When driving at speeds below 30 km/h, you
will see parking symbol
; as a status indi-
cator
in the instrument cluster. When a park-
ing space has been detected, an arrow
towards the right or the left also appears.
Active Parking Assist only displays parking
spaces on the front-passenger side as stand-
ard. Parking spaces on the driver's side are
displayed as soon as the turn signal on the
driver's side is activated. When parking on the
driver's side, this must remain switched on
until you acknowledge the use of Active Park-
ing Assist by pressing the a button on the
multifunction steering wheel.
A parking space is displayed while you are
driving past it, and until you are approx-
imately 15 m away from it.
Parking G
WARNING
Active Parking Assist merely aids you by inter-
vening
actively in the steering. There is a risk
of accident if you do not apply the brakes
yourself.
Always apply the brakes yourself when park-
ing and manoeuvring.
Active Parking Assist does not support you
with parking spaces parallel to the direction
of travel if:
R the parking space is on a kerbstone
R the parking space is apparently blocked,
for example by foliage or grass paving
blocks
R the range of movement is too small
R the parking space is bordered by an obsta-
cle which is not clearly defined such as a
tree or a trailer
X Stop the vehicle when the parking symbol
shows the desired parking space in the
instrument cluster.
X Vehicles with manual transmission: shift to
reverse gear. Vehicles with automatic transmission: shift
into position R.
The Start Park Assist? Yes: OK No:
%
message appears in the multifunction
display.
X To cancel the procedure: press the
% button on the multifunction steering
wheel or pull away.
or
X To park using Active Parking Assist:
press
the a button on the multifunction
steering wheel.
The Park Assist active Accelerate
and brake Observe surroundings mes-
sage appears in the multifunction display.
X Release the multifunction steering wheel.
X Reverse the vehicle, being ready to brake
at all times. Do not exceed a maximum
speed of approximately
10 km/h when
reversing. Otherwise, Active Parking Assist
will be cancelled.
i In tight parking spaces, you will achieve
the best parking results by backing up as
far as possible. When doing so, also
observe the PARKTRONIC messages.
X Stop as soon as PARKTRONIC sounds the
continuous warning tone, if not before.
Manoeuvring
may be required in tight park-
ing spaces.
Vehicles with manual transmission: the Park
Assist active Engage forward gear
Observe
surroundings message appears in
the multifunction display.
Vehicles with automatic transmission: the
Park Assist active Select D Observe
surroundings message appears in the mul-
tifunction display.
X Vehicles with manual transmission: while
the vehicle is stationary, shift to first gear.
Vehicles with automatic transmission:
select transmission position D while the
vehicle is stationary.
Active
Parking Assist immediately steers in
the other direction. 188
Driving systems
Driving and parking