2004 MERCEDES-BENZ SL500 brake

199 Controls in detail
Driving systems
Distronic menu in the control system
In the Distronic menu you can read the cur-
rent settings for Distronic. What appears in
the left display field depends on whether
the Distronic is turned on or off.
Press button è or ÿ repeatedly
until you see one of the following dis-
plays.Distronic deactivated
When Distronic is deactivated you will see
the standard display in the left display
field.
1Vehicle ahead, if detected
2Actual distance to vehicle ahead
3Preset distance threshold to vehicle
ahead
4Your vehicle
5Symbol for activated distance warning
function
Warning!
G
The Distronic brakes your vehicle with a
maximum of 6.5 ft/s
2 (2 m/s
2). This corre-
sponds to about 20% of the maximum decel-
eration ability of your vehicle.
Distronic brakes the vehicle in an effort to
restore the preset distance or to maintain
the speed. The brake pedal is automatically
applied as this happens which results in the
brake pedal moving.
Keep driver’s foot area clear at all times, in-
cluding the area under the brake pedal. Ob-
jects stored in this area may impair pedal
movement which could interfere with the
braking ability of the Distronic system.
Do not place your foot under the brake pedal
– your foot could become caught.

200 Controls in detailDriving systemsDistronic activated
When Distronic is activated the DTR sym-
bol and the set speed are seen in the left
display.
1Symbol for activated Distronic
2Set speedCruise control lever
The Distronic system is operated by means
of the cruise control lever.
The cruise control lever is the uppermost
lever found on the left-hand side of the
steering column.
1Set current or higher speed
2Set current or lower speed
3Deactivate Distronic
4Resume at last set speedActivating Distronic
You can activate Distronic if


you are driving between 25 mph
(40 km/h) and 110 mph (180 km/h)


the ESP is activated (
page 78)
When Distronic is activated the speedome-
ter display will show a message such as
DTR 60 mph
.
If Distronic is deactivated, the speedome-
ter display will show the message
DTR --- mph
.
In the following cases you cannot activate
Distronic:


up to two minutes after starting the en-
gine


when you brake


if you have set the parking brake


if the gear selector lever is in
positionP, R, or N.


if the ESP is switched off

202 Controls in detailDriving systemsSetting a lower speed
Briefly tip the cruise control in direction
of arrow2 (
page 200) to decrease
the vehicle speed in increments of
5 mph (Canada: 10 km/h).
The new speed is set.
Fine adjustment in 1 mph
(Canada: 1 km/h) increments
Faster

Briefly tip the cruise control lever in the
direction of arrow4 (
page 200).Setting to last stored speed (“Resume”
function)

Briefly tip the cruise control lever in the
direction of arrow4 (
page 200).
Distronic is set to the last stored
speed.

Remove your foot from the accelerator
pedal.Deactivating Distronic
There are several ways to deactivate the
Distronic system:

Briefly tip the cruise control lever in the
direction of arrow3 (
page 200).
or

Step on the brake pedal.
Distronic will be deactivated. The last
speed set will be stored into memory.
iWhen you use the cruise control lever
to decelerate, the transmission will au-
tomatically downshift if the rate of de-
celeration is too low.
Warning!
G
The speed stored in memory should only be
set again if prevailing road conditions per-
mit. Possible acceleration or deceleration
differences arising from returning to the pre-
set speed could endanger yourself and oth-
ers.
iThe last stored speed is deleted when
you turn off the engine.

203 Controls in detail
Driving systems
Distronic deactivates automatically when

you set the parking brake


you drive slower than 25 mph
(40 km/h)


the ESP is active (
page 78) or you de-
activate the ESP


You move the gear selector lever into
positionN.
A signal will sound. The
DTR off
mes-
sage appears in the speedometer dis-
play for approximately five seconds.Setting the following distance in
Distronic
You can set the specified following for Dis-
tronic by varying the time setting between
1.0 and 2.0 seconds. Using this time set-
ting and the current speed of your vehicle,
Distronic calculates and sets the required
following distance to the vehicle ahead.
The set distance will be shown in the
speedometer display field.
The thumbwheel for making the time set-
ting is located on the lower section of the
center console.1Distance warning function on/off
switch
2Thumbwheel for setting distance
Increasing distance
Increasing the distance setting tells Dis-
tronic to maintain a greater following dis-
tance to the vehicle ahead.

Turn thumbwheel2 towards ¯.
Warning!
G
Distronic switches off and releases the
brakes when the vehicle decelerates below
the minimum speed of 25 mph (40 km / h)
by operation of the system. At that time the
driver must apply the brakes in order to re-
duce vehicle speed further or bring it to a
stop.
Warning!
G
It is up to the driver to exercise discretion to
select the appropriate setting given road
conditions, traffic, driver’s preferred driving
style and applicable laws and driving recom-
mendations for safe following distance.

204 Controls in detailDriving systemsDecreasing distance
Decreasing the distance setting tells Dis-
tronic to maintain a smaller following dis-
tance to the vehicle ahead.
Turn thumbwheel2 towards ®.
Distance warning function
When Distronic is deactivated, this func-
tion will continue to warn you if you are fol-
lowing too close to the vehicle ahead:


The DTR warning lamp E 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 vehicle
ahead.Activating

Press switch1.
The indicator lamp on the switch
comes on. A loudspeaker symbol ap-
pears in the speedometer display
(page 199).
Deactivating

Press switch1.
The indicator lamp on the switch goes
out. No loudspeaker symbol appears in
the speedometer display.
Warning!
G
If the DTR warning lamp (red)
E
in the
speedometer dial comes on while driving
and/or an intermittent warning sounds, im-
mediate attention on the 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 re-
sult in an emergency braking application.
Especially depending on road surface condi-
tions and driver reaction, this will not always
enable you to avoid a collision.
iComplex driving situations are not al-
ways fully recognized by Distronic. This
could result in wrong or missing dis-
tance warnings.

205 Controls in detail
Driving systems
Driving with Distronic
This section describes a number of driving
situations where special precaution is re-
quired on the part of the driver. Be pre-
pared to brake in such situations. This will
deactivate the Distronic system.The most likely cause for a malfunctioning
system is a dirty sensor (located behind
the hood grille), especially at times of snow
and ice or heavy rain. In such a case, Dis-
tronic will switch off, and the message
Distronic Currently unavailable! See
Oper’s Man.
appears in the multifunction
display.
For cleaning and care of the Distronic sen-
sor, see “Cleaning the Distronic* system
sensor cover” (page 277).
Warning!
G
Distronic works to maintain the speed se-
lected by the driver unless a moving obsta-
cle proceeding directly ahead of it in the
same travel direction is detected (e.g. fol-
lowing another vehicle ahead of you at a dis-
tance set by Distronic). This means that:

Your vehicle can pass another vehicle
after you change lanes.


While in a sharp turn or if the vehicle in
front is in a sharp turn, Distronic could
lose sight of a vehicle traveling in front
of it. Your vehicle could then accelerate
to the previously selected speed.
Distronic regulates only the distance be-
tween your vehicle and those directly ahead
of it, but does not register stationary objects
in the road, e.g.:

a stopped vehicle in a traffic jam


a disabled vehicle


an oncoming vehicle
The driver must always be on the alert, ob-
serve all traffic and intercede as required by
steering or braking the vehicle.
Warning!
G
Distronic should not be used in snowy or icy
road conditions.

206 Controls in detailDriving systemsTurns and bends
In turns or bends, Distronic may not detect
a moving vehicle in front, or it may detect
one too soon. This may cause your vehicle
to brake late or unexpectedly.Offset driving
A vehicle traveling in your lane but offset
from your direct line of travel may not be
detected by Distronic. There will be insuffi-
cient distance to the vehicle ahead.Lane changing
Distronic has not yet detected the vehicle
changing lanes. There will be insufficient
distance to the vehicle ahead.

210 Controls in detailDriving systemsParktronic* (Parking assist)
The Parktronic system is an electronic aid
designed to assist the driver during park-
ing maneuvers. It visually and audibly indi-
cates the relative distance between the
vehicle and an obstacle.
The Parktronic system is automatically ac-
tivated when you switch on the ignition
and release the parking brake. The Park-
tronic system deactivates at speeds above
11 mph (18 km/h). At lower speeds the
Parktronic system turns on again.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 bumperWarning!
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 rests 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 277).
Interference caused by other ultrasonic sig-
nals (e.g. working jackhammers or the air
brakes of trucks) can cause the system to
send erratic indications, and should be tak-
en into consideration.
Warning!
G
Make sure that no persons or animals are in
the area in which you are maneuvering. Oth-
erwise you run the risk of causing injury.