2008 MERCEDES-BENZ SL55AMG brakes

176 Controls in detail
Automatic transmission
Stopping
When you stop briefly, e.g. at traffic lights:
Leave the transmission in gear.
Hold the vehicle with the brake.
When you stop for a longer period of time
with the engine idling and/or on a hill:
Set the parking brake.
Move the gear selector lever to park
positionP.Maneuvering
When you maneuver in tight areas,
e.g. when pulling into a parking space:
Control the vehicle speed by gradually
releasing the brakes.
Accelerate gently.
Never abruptly step on the accelerator.
Working on the vehicle
Gear ranges
With the gear selector lever in drive
positionD and driving in program modeC
orS, you can select a gear range for the
automatic transmission to operate within.
Gear selector lever (
page 179):
You can limit the gear range by pressing
the gear selector lever to the left (D-), and
reverse the gear range limit by pressing
the gear selector lever to the right (D+).
Steering wheel gearshift control*
(
page 180):
You can limit the gear range by pulling the
left gearshift paddle on the steering wheel
gearshift control, and reverse the gear
range limit by pulling the right gearshift
paddle on the steering wheel gearshift
control.Warning!G
When working on the vehicle, set the
parking brake and move gear selector lever
to park positionP. Otherwise the vehicle
could roll away.

215 Controls in detail
Driving systems
1Setting current or higher speed
2Setting current or lower speed
3Canceling the cruise control
4Activating the cruise control or resum-
ing to last set speedActivating cruise control
You can activate the cruise control when
the vehicle speed is above
20 mph (30 km/h).
In the following cases you cannot activate
the cruise control:

when you brake

when you have set the parking brake

when the gear selector lever is set to
position P, R, or N

when the ESP® is switched off
Setting current speed
Accelerate or decelerate to the desired
speed.
Briefly lift the cruise control lever in
direction of arrow1 or depress in
direction of arrow2.
The current speed is set.
Remove your foot from the accelerator
pedal.
The cruise control is activated.
The currently set speed appears in the
status indicator of the multifunction
display:

USA only:
CRUISE XXX MPH

Canada only:
Ñ
XXX Km/h
Warning!G
The cruise control brakes automatically so
that the set speed is not exceeded.
Keep in mind that the cruise control is a con-
venience system designed to assist the driv-
er during vehicle operation. The driver is and
must always remain responsible for the ve-
hicle’s speed and for safe brake operation.
iThe vehicle speed displayed in the speedom-
eter can briefly vary from the speed setting for
the cruise control system.
iOn uphill grades, the cruise control may not
be able to maintain the set speed. Once the
grade eases, the set speed will be resumed.
On downhill grades, the cruise control maintains
the set speed by braking with the vehicle’s brake
system. In addition, on longer downhill grades
the automatic transmission will downshift auto-
matically.

221 Controls in detail
Driving systems
If Distronic detects a vehicle directly
ahead, the Distronic indicator lamp E
in the speedometer dial comes on white.
If Distronic calculates that there is a dan-
ger of collision:

The distance warning lamp E in the
speedometer comes on red.

An intermittent warning sounds.
Immediately apply the brake to avoid a
collision.
Under no circumstances should the
driver await the intermittent warning
sound before braking. See the follow-
ing warning note.
The intermittent warning sound ceases
and the red distance warning
lampE goes out when the neces-
sary distance to the vehicle ahead is
established again.
Warning!G
An intermittent warning sounds and the
distance warning lamp (red) E in the
speedometer dial is illuminated if the
Distronic system calculates that the
distance to the vehicle ahead and your
vehicle’s current speed indicate that
Distronic will not be capable of slowing the
vehicle sufficiently to maintain the preset
following distance, which creates a danger
of a collision.
Immediately brake the vehicle to increase
the distance to the preceding vehicle. The
warning sound is intended as a final caution
that you have not interceded with your own
braking inputs to avoid a potentially danger-
ous situation. Do not wait for the operation
of the warning signal to intercede with your
own braking, as that will result in potentially
dangerous emergency braking which will
not always result in an impact being
avoided.
Tailgating increases the risk of an accident.
Warning!G
Distronic brakes your vehicle with a maxi-
mum deceleration of 6.5 ft/s2 (2 m/s2). This
corresponds to about 20% of the maximum
deceleration ability of your vehicle.
Distronic brakes the vehicle in an effort to
restore the preset distance or to maintain
the set speed.

224 Controls in detail
Driving systems
Setting the current speed
Accelerate or decelerate to the desired
speed.
Briefly lift the cruise control lever in
direction of arrow1 or depress in
direction of arrow2 (
page 223).
Distronic is activated and the current
speed is set.
The currently set speed appears in the
status indicator of the multifunction
display:

USA only:
DTR XXX MPH

Canada only:
DTR XXX Km/h
Remove your foot from the accelerator
pedal.Setting a higher speed
Briefly tip the cruise control lever in
direction of arrow1 (
page 223) to
increase the vehicle speed in incre-
ments of 5 mph (Canada: 10 km/h).
The new speed is set.Setting a lower speed
Briefly tip the cruise control lever in
direction of arrow2 (
page 223) to
decrease the vehicle speed in incre-
ments of 5 mph (Canada: 10 km/h).
The new speed is set.
Fine adjustment in 1 mph
(Canada: 1 km/h) increments
Faster
Briefly pull the cruise control lever in
direction of arrow4 (
page 223).
iIf you do not take your foot off of the accel-
erator but continue to accelerate past the set
speed, the following message will appear in the
multifunction display:
DTR Passive.
The distance to slower moving vehicles in front
of you will not be set. Your vehicle speed will
then be determined only by the accelerator
pedal position.
iDepressing the accelerator pedal does not
deactivate Distronic. After brief acceleration
(e.g. for passing), the cruise control will resume
the last speed set.
iWhen you use the cruise control lever to
decelerate, the brakes will be applied to support
deceleration.
In addition, the transmission will automatically
downshift on long downhill grades.

225 Controls in detail
Driving systems
Setting to last stored speed
(“Resume” function)
Briefly pull the cruise control lever in
direction of arrow4 (
page 223).
Distronic resumes the last stored
speed or, if no speed is stored, it will
set and store the current speed.
Remove your foot from the accelerator
pedal.Deactivating Distronic
There are several ways to deactivate the
Distronic system:
Step on the brake pedal.
or
Briefly push the cruise control lever in
direction of arrow3 (
page 223).
Distronic will be deactivated. The last set
speed will be stored into memory.
The following message appears in the mul-
tifunction display for approximately
5 seconds:
DTR Off
Warning!G
The set speed stored in memory should only
be set again if prevailing road conditions
permit. Possible acceleration or decelera-
tion differences arising from returning to the
preset speed could caused an accident
and/or serious injury to you and others.
iThe last stored set speed is deleted when
the engine is turned off.
iDistronic deactivates automatically when

you depress the parking brake pedal

the vehicle speed is below
20 mph (30 km/h) (
page 223)

the ESP® is in operation or switched off with
the ESP® switch (page 93)

you move the gear selector lever into
positionN
An acoustic warning sounds and the
message
DTR Off appears in the multifunc-
tion display for approximately 5 seconds.
Warning!G
Distronic switches off and releases the
brakes when the vehicle decelerates below
the minimum speed of 20 mph (30 km/h)
by operation of the system. At that time the
driver must apply the brakes in order to
reduce vehicle speed further or bring it to a
stop.

229 Controls in detail
Driving systems
Narrow vehicles
Because of their narrow profile, the vehi-
cles traveling near the outer edges of the
lane have not yet been detected by
Distronic. There will be insufficient dis-
tance to the vehicles ahead.Distance warning function*
When Distronic* is deactivated, this func-
tion will continue to warn you when recog-
nizing a stationary obstacle or a slower
vehicle moving in your vehicle’s path and
the danger of a collision exists:

The distance warning lamp E in the
speedometer comes on red.

An intermittent warning will sound if
necessary.
If these warnings are issued, you must
brake manually to maintain a safe distance
and avoid a collision with the preceding
vehicle.
When depressing the brake pedal, the
warning sound ceases. The warning sound
will also cease when the distance to the
preceding vehicle is sufficient again with-
out applying the brakes. In this case, the
distance warning lamp will also go out.
Warning!G
If the distance warning lamp (red) E in
the speedometer comes on while driving
and/or an intermittent warning sounds,
immediate attention on part of the driver is
required.
As required by the traffic situation, apply the
brakes and navigate around a possible ob-
stacle. However, do not drive by relying on
the distance warning function, as this will
result in an emergency braking application.
This will not always enable you to avoid a
collision, especially when traveling on vary-
ing road surface conditions and with varying
driver reaction.
iComplex driving situations are not always
fully recognized by the distance warning
function. This could result in wrong or missing
distance warnings.

233 Controls in detail
Driving systems
Suspension for sporty driving style
The setting for sporty driving is selected
when indicator lamp2 is on.
Press button1.
Indicator lamp2 comes on.
Suspension for regular driving style
The setting for regular driving is selected
when indicator lamp2 is off.
Press button1.
Indicator lamp2 goes out.
Parktronic system* (Parking assist)
The Parktronic system is an electronic aid
with ultrasonic sensors. It is designed to
assist the driver during parking maneu-
vers. It visually and audibly indicates the
relative distance between the vehicle and
an obstacle.
The Parktronic system is automatically
activated when you switch on the ignition,
release the parking brake, or place the
gear selector lever in position D, R, or N.
Warning!G
Parktronic is a supplemental system. It is
not intended to, nor does it replace, the
need for extreme care. The responsibility
during parking and other critical maneuvers
always remains with the driver.
Special attention must be paid to objects
with smooth surfaces or low silhouettes
(e.g. trailer couplings, painted posts, or road
curbs). Such objects may not be detected by
the system and can damage the vehicle.
The operational function of the Parktronic
system can be affected by dirty sensors, es-
pecially at times of snow and ice. See
“Cleaning the Parktronic* system sensors”
(
page 337).
Warning!G
Make sure no persons or animals are in the
area in which you are maneuvering. Other-
wise you run the risk of causing injury.
!Interference caused by other ultrasonic sig-
nals (e.g. working jackhammers, car wash, or the
air brakes of trucks) can cause the system to
send erratic indications, and should be taken
into consideration.

234 Controls in detail
Driving systems
The Parktronic system deactivates at
speeds exceeding approximately
11 mph (18 km/h). At lower vehicle
speeds the Parktronic system turns on
again. The Parktronic system also deacti-
vates when you place the gear selector le-
ver in position P or depress the parking
brake pedal.
The Parktronic system monitors the sur-
roundings of your vehicle with six sensors
in the front bumper and four sensors in the
rear bumper.
1Sensors in the front bumperRange of the sensorsFront sensors
Rear sensorsiTo function properly, the sensors must be
free of dirt, ice, snow and slush. Clean the
sensors regularly, being careful not to scratch or
damage the sensors, see “Cleaning the
Parktronic system* sensors” (
page 337).
Centerapprox. 40 in (100 cm)
Cornersapprox. 24 in (60 cm)
Centerapprox. 48 in (120 cm)
Cornersapprox. 32 in (80 cm)
!During parking maneuvers, pay special at-
tention to objects located above or below the
height of the sensors (e.g. planters or trailer
hitches). The Parktronic system will not detect
such objects at close range and damage to your
vehicle or the object may result.
Ultrasonic signals from outside sources (e.g.
truck air brakes, car wash, or jackhammers) may
impair the operation of the Parktronic system.