2012 MERCEDES-BENZ SL ROADSTER brakes

You should pay special attention to road con-
ditions when temperatures are around the
freezing point.
For more information on driving with snow
chains, see (Y page 599).
For more information on driving with summer tyres, see (Y page 598).
Observe the notes in the "Winter operation"
section (Y page 598). Driving systems
Cruise control
General notes Cruise control maintains a constant road
speed for you. It brakes automatically in order
to avoid exceeding the set speed. On long and
steep downhill gradients, especially if the
vehicle is laden, you must select a lower gear 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 tooquickly.
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.
Important safety notes If you fail to adapt your driving style, cruise
control can neither reduce the risk of acci-
dent nor override the laws of physics. Cruise
control cannot take road, weather and traffic
conditions into account. Cruise control 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 maintaining lane. Do not use cruise control:
R in road and traffic conditions which do not
allow you to maintain a constant speed, e.g.
heavy traffic or winding roads.
R on slippery roads. Braking or accelerating
may 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 stored speed.
Cruise control lever Cruise control lever
:
To store the current speed or a higher
speed
; LIM indicator lamp
= To store the current speed and to call up
the last stored speed
? To store the current speed or a lower
speed
A To switch between cruise control and var-
iable SPEEDTRONIC
B To deactivate cruise control
You can operate cruise control and variable
SPEEDTRONIC with the cruise control lever.
LIM indicator lamp ;on the cruise control
lever indicates which system you have selec- ted:
R LIM indicator lamp ;
; off: cruise control
is selected.
R LIM indicator lamp ; ;on: variable
SPEEDTRONIC is selected. 182
Driving systemsDriving and parking

When you activate cruise control, the stored
speed is shown in the multifunction display
for five seconds. The speed is then perma-
nently displayed in the status indicator
together with the ¯symbol.
Selecting cruise control Cruise control lever
X Check whether LIM indicator lamp :is off.
If it is off, cruise control is already selected. If it is not, press the cruise control lever in
the direction of arrow ;.
LIM indicator lamp :in the cruise control
lever goes out. Cruise control is selected.
Storing, maintaining and calling up a
speed Storing and maintaining the speed
Cruise control lever X
Accelerate the vehicle to the desired
speed.
X Briefly press the cruise control lever up :
or down ;.
X Remove your foot from the accelerator
pedal.
Cruise control is activated. The vehicle
automatically maintains the stored speed.
You can store the current speed if you are
driving faster than 30 km/h.
i Cruise control may be unable to maintain
the stored speed on uphill gradients. The
stored speed is resumed when the gradient evens out. Cruise control maintains the
stored speed on downhill gradients by
automatically braking the vehicle.
Storing or calling up the 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. Cruise control lever Driving systems
183Driving and parking Z

DISTRONIC PLUS
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.
On long and steep downhill gradients, espe-
cially if the vehicle is laden, you must select a lower gear 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 a slower-moving vehicle is detected in front, DISTRONIC PLUS brakes your vehicle. It
maintains the preset distance to the vehicle infront.
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.
For DISTRONIC PLUS to assist you, the radar
sensor system must be operational.
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 ofyou, it operates in the speed range between
0 km/h and 200 km/h.
Do not use DISTRONIC PLUS while driving on roads with steep gradients. 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. Driving syste
ms
185Driving an d parking Z

!
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
accident nor override the laws of physics.
DISTRONIC PLUS cannot take account of
road and weather conditions or traffic condi-
tions. 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 correctly in 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 if there is:
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. 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.
Cruise control lever Cruise control lever
:
To store the current speed or a higher
speed
; To set the specified minimum distance
= LIM indicator lamp
? To store the current speed and to call up
the last stored speed
A To store the current speed or a lower
speed
B To switch between DISTRONIC PLUS and
variable SPEEDTRONIC
C To deactivate DISTRONIC PLUS
You can operate DISTRONIC PLUS and varia- ble SPEEDTRONIC with the cruise control
lever.
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
SPEEDTRONIC is selected. 186
Driving systemsDriving and parking

Selecting DISTRONIC PLUS
Cruise control lever
X Check whether LIM indicator lamp :is off.
If it is off, DISTRONIC PLUS is already selec- ted.
If it is not, press the cruise control lever in
the direction of arrow ;.
LIM indicator lamp :in the cruise control
lever goes out. DISTRONIC PLUS is selec-
ted.
Activating DISTRONIC PLUS; storing,
maintaining and calling up a speed Important safety notes
! 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
To activate DISTRONIC PLUS, the following
conditions must be fulfilled:
R the engine must be running. It may take up
to two minutes of driving before DIS-
TRONIC PLUS is ready for use.
R your vehicle must not be secured by the
electric parking brake.
R ESP ®
must be activated.
R the transmission must be in position D.
R the bonnet must be closed. R
the driver's door must be closed when you
shift from Pto Dor your seat belt must be
fastened.
R the front-passenger door must be closed.
R the vehicle must not be skidding.
Activating Cruise control lever
X Briefly pull the cruise control lever towards
you ;, or press it up :or down =.
DISTRONIC PLUS is activated.
X Keep the cruise control lever pressed up :
or down =until the desired speed has
been set.
X Remove your foot from the accelerator
pedal.
Your vehicle adapts its speed to that of the
vehicle in front, but only up to the desired
stored speed.
If the vehicle in front has been detected and is
shown in the multifunction display, you can
also activate DISTRONIC PLUS when driving
at speeds below 30 km/h. If the vehicle in
front is no longer detected and displayed, for
example because it has changed lanes, DIS-
TRONIC PLUS is deactivated. You will hear a
warning tone if this is the case.
i If you do not fully release the accelerator
pedal, the DISTRONIC PLUS inactive
DISTRONIC PLUS inactive
message appears in the multifunction dis-
play. The set distance to a slower-moving
vehicle in front will then not be maintained. You will be driving at the speed you deter-
mine by the position of the accelerator
pedal. Driving systems
187Driving and parking Z

Pulling away and driving
Cruise control lever
DISTRONIC PLUS is deactivated when you
depress the brake, except when the vehicle is stationary.
X If the vehicle in front pulls away: remove
your foot from the brake pedal.
X Briefly pull the cruise control lever towards
you ;, or up :or down =.
or X Accelerate briefly.
Your vehicle pulls away and adapts its
speed to that of the vehicle in front.
If there is no vehicle in front, DISTRONIC
PLUS operates in the same way as cruise
control.
If DISTRONIC PLUS detects that the vehicle in front has slowed down, it 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.
If DISTRONIC PLUS detects a faster-moving
vehicle in front, it increases the driving speed.
However, the vehicle is only accelerated up to the speed you have stored. Changing lanes
If you wish to move into the overtaking lane (in
countries where traffic drives on the right, thepassing lane is the left-hand lane), DIS-
TRONIC PLUS assists you if:
R you are driving faster than 60 km/h
R DISTRONIC PLUS is maintaining the dis-
tance to a vehicle in front
R you have switched on the corresponding
turn signal
R DISTRONIC PLUS does not detect a danger
of collision
If these conditions are met, your vehicle is
accelerated. Acceleration will be interrupted
if changing lanes takes too long or if the dis-
tance between your vehicle and the vehicle in front becomes too small.
Vehicles with COMAND Online
i The following function is not operational
in all countries.
DISTRONIC PLUS uses additional information
from your navigation system so that it can
react appropriately to certain traffic situa-
tions. This is the case if, while following a
vehicle, DISTRONIC PLUS is active and you:
R approach or drive around a roundabout
R approach a T-junction
R turn off at a motorway exit
Even if the vehicle in front leaves the detec-
tion range, DISTRONIC PLUS temporarily
maintains the current driving speed and does not accelerate. This is based on the current
map data in the navigation system. 188
Driving systemsDriving and parking

Example: roundabout
The current speed is maintained:
R approximately ten seconds before the
roundabout/T-junction and for approx-
imately 1.5 second s when driving onthe
roundabout
R approximately twelve seconds before
reaching a motorway exit and approx-
imately four seconds after the motorway
exit
Afterwards, the vehicle accelerates back to
the set speed you specified.
Stopping G
WARNING
When leaving the vehicle, even if it is braked
only by DISTRONIC PLUS, it could roll away if:
R there is a malfunction in the system or in
the voltage supply.
R DISTRONIC PLUS has been deactivated
with the cruise control lever, e.g. by a vehi-
cle occupant or from outside the vehicle.
R the electrical system in the engine com-
partment, the battery or the fuses have
been tampered with.
R the battery is disconnected.
R the accelerator pedal has been depressed,
e.g. by a vehicle occupant.
There is a risk of an accident.
If you wish to exit the vehicle, always turn off
DISTRONIC PLUS and secure the vehicle
against rolling away.
Deactivate DISTRONIC PLUS (Y page 192).If DISTRONIC PLUS detects that the vehicle in
front is stopping, it brakes your vehicle until it
is stationary.
Once your vehicle is stationary, it remains
stationary and you do not need to depress the
brake. After a short period the vehicle is
secured by the electric parking brake, thus
relieving the service brake.
Depending on the specified minimum dis-
tance, your vehicle will come to a standstill at a sufficient distance behind the vehicle in
front. The specified minimum distance is set
using the control on the cruise control lever.
The electric parking brake secures the vehicle
automatically if DISTRONIC PLUS is activated
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
If a fault occurs, then the transmission may
also be shifted into position Pautomatically.
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. Driving systems
189Driving and parking Z

Vehicles which are not driving in the mid-
dle of their lane DISTRONIC PLUS may not detect vehicles
which are not driving in the middle of their
lane. The distance to the vehicle in front will
be too short.
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 mistakenly detect
vehicles that are crossing your lane. Activat-
ing DISTRONIC PLUS at traffic lights with
crossing traffic, for example, could cause
your vehicle to pull away unintentionally.
SPEEDTRONIC
General notes SPEEDTRONIC brakes automatically so that
you do not exceed the set speed. On long and steep downhill gradients, especially if the Driving systems
193Driving and parking Z