2008 MERCEDES-BENZ SL55AMG automat

214 Controls in detail
Driving systems
The driving systems of your vehicle are
described on the following pages:

Cruise control and Distronic*, with
which the vehicle can maintain a preset
speed

Distance warning function* (only avail-
able with Distronic*), which warns of
stationary objects or slower moving ve-
hicles that you are closing in on too
quickly

ABC with vehicle level control systems,
with which you can change vehicle sus-
pension characteristics

Parktronic*, which assists the driver
during parking maneuvers
For information on the BAS, ABS, ESP
®,
and the electro-hydraulic brake system,
see “Driving safety systems” (
page 89).
Cruise control
The cruise control automatically maintains
the speed you set for your vehicle.
The use of the cruise control is recom-
mended for driving at a constant speed for
extended periods of time.
You can set or resume the cruise control at
any speed above 20 mph (30 km/h).
The cruise control function is operated by
means of the cruise control lever.
The cruise control lever is the uppermost
lever on the left-hand side of the steering
column (
page 24).
Warning!G
The cruise control is a convenience system
designed to assist the driver during vehicle
operation. The driver is and must always
remain responsible for the vehicle’s speed
and for safe brake operation.
Only use the cruise control if the road,
traffic, and weather conditions make it ad-
visable to travel at a constant speed.

The use of the cruise control can be dan-
gerous on winding roads or in heavy traf-
fic because conditions do not allow safe
driving at a constant speed.

The use of the cruise control can be dan-
gerous on slippery roads. Rapid changes
in tire traction can result in wheel spin
and loss of control.

Deactivate the cruise control when driv-
ing in fog.
The “Resume” function should only be oper-
ated if the driver is fully aware of the previ-
ously set speed and wishes to resume this
particular preset speed.

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.

217 Controls in detail
Driving systems
Setting a higher speed
Lift the cruise control lever in direction
of arrow1 (
page 215) and hold it
there until the desired speed is
reached.
Release the cruise control lever.
The new speed is set.
Setting a lower speed
Depress the cruise control lever in
direction of arrow2 (
page 215) and
hold it there until the desired speed is
reached.
Release the cruise control lever.
The new speed is set.Fine adjustment in 1 mph
(Canada: 1 km/h) increments
Faster
Briefly tip the cruise control lever in
direction of arrow1 (
page 215).
Slower
Briefly tip the cruise control lever in
direction of arrow2 (
page 215).Setting to last stored speed
(“Resume” function)
Briefly pull the cruise control lever in
direction of arrow4 (
page 215).
The cruise control resumes to the last
set speed or, if no speed is stored, it
will set and store the current speed.
Remove your foot from the accelerator
pedal.
The selected speed appears in the mul-
tifunction display.iWhen you use the cruise control lever to de-
celerate, the brake system will automatically
brake the vehicle if the engine’s braking power
does not brake the vehicle sufficiently.
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 cause an accident
and/or serious injury to you and others.

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.

230 Controls in detail
Driving systems
1Distance warning function switchActivating
Press switch1.
The indicator lamp on the switch
comes on. A loudspeaker symbol
appears in the right multifunction
display (
page 222).
Deactivating
Press switch1 once more.
The indicator lamp on the switch goes
out. No loudspeaker symbol appears in
the right multifunction display.
Active Body Control (ABC)
The ABC system is an active,
computer-controlled system that hydrauli-
cally adjusts the suspension at all four
wheels in response to various driving
situations. It automatically selects the
optimum suspension tuning and ride
height for your vehicle.
Vehicle level control
Your vehicle automatically adjusts its ride
height to:

increase vehicle safety

reduce fuel consumption
Warning!G
To help avoid personal injury, keep hands
and feet away from wheel housing area, and
stay away from under the vehicle when low-
ering the vehicle chassis.

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.

236 Controls in detail
Driving systems
As your vehicle approaches an object, one
or more distance segments will illuminate,
depending on the distance. When the
eighth distance segment illuminates, you
have reached the minimum distance.

Front area: An intermittent acoustic
warning will sound as the first red
distance segment illuminates and a
constant acoustic warning lasting a
maximum of 2 seconds will sound for
the second distance segment.
The signal is canceled when the gear
selector lever is placed in position P or
the parking brake is set.

Rear area: An intermittent acoustic
warning will sound when the first dis-
tance segment illuminates. This signal
quickens with each additional distance
segment lit. When the eighth distance
segment illuminates, the acoustic
warning becomes a constant signal.
The signal is canceled when the gear
selector lever is placed in positionD
orP or the parking brake is set.Switching the Parktronic system
on/off
You can switch off the Parktronic system
manually.
The Parktronic switch is located in the
lower part of the center console.
1Parktronic switch
2Indicator lamp
Switching off
Press Parktronic switch1.
Indicator lamp2 comes on.Switching on
Press Parktronic switch1 once more.
Indicator lamp2 goes out.
Parktronic system malfunction
If only the red distance segments illumi-
nate and an acoustic warning sounds,
there is a malfunction in the Parktronic
system. The Parktronic system will auto-
matically switch off after 20 seconds and
the indicator lamp in the Parktronic switch
comes on.
Have the Parktronic system checked
by an authorized Mercedes-Benz
Center as soon as possible.
iThe Parktronic system switches on automat-
ically when you switch on the ignition
(
page 40).