2005 MERCEDES-BENZ S CLASS brake

219 Controls in detail
Driving systems
Distronic displays in the speedometer
dialSet speedIf Distronic is activated, one or two seg-
ments come on around the set speed.
SegmentsIf Distronic detects a vehicle directly
ahead, the segments from the speed of the
vehicle ahead to the set speed come on.
If Distronic calculates that there is a dan-
ger of collision (
page 225):


The red Distronic warning lampl in
the instrument cluster comes on.


An intermittent warning sounds.

Immediately brake the vehicle 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 Distronic warning
lampl goes out when the neces-
sary distance to the vehicle ahead is
again established.
iThe vehicle speed displayed on the
speedometer can briefly vary from the
speed setting on the Distronic system.

220 Controls in detailDriving systems
Distronic menu in the control system
In the Distronic menu you see the current
settings for Distronic. What appears in the
display depends on whether Distronic and
the distance warning function are turned
on or off.
Press buttonè orÿ repeatedly
until you see one of the following dis-
plays.
Warning!
G
An intermittent warning sounds and the
Distronic warning lampl in the instru-
ment cluster 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 ca-
pable of slowing the vehicle sufficiently to
maintain the preset following distance,
which creates a danger of a collision.
Immediately brake your vehicle to increase
the distance between your vehicle and the
vehicle in front of you. The warning sound is
intended as a final caution that you have not
interceded with your own braking inputs to
avoid a potentially dangerous situation. Do
not wait for the operation of the warning sig-
nal to intercede with your own braking, as
that will result in potentially dangerous
emergency braking which will not always re-
sult in an impact being avoided.
Tailgating increases the risk of an accident.
Warning!
G
Distronic brakes your vehicle with a maxi-
mum of 6.5 ft/s
2 (2 m/s
2). This corre-
sponds 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 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.

222 Controls in detailDriving systemsActivating 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 82)
If Distronic has not been activated after
pressing the cruise control lever you will
see the message
---
in the multifunction
display.
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 offSetting the current speed

Accelerate or decelerate to the desired
speed.

Briefly lift the cruise control lever in di-
rection of arrow1 or depress in direc-
tion of arrow2.
Distronic is activated and the current
speed is set.

Remove your foot from the accelerator
pedal.Setting a higher speed

Briefly tip the cruise control lever in di-
rection of arrow1 (
page 221) to in-
crease vehicle speed in increments of
5 mph (Canada: 10 km/h).
The new speed is set.
The stored speed is displayed in the
multifunction display for approximately
five seconds (
page 221), and one or
two segments around the stored speed
come on the speedometer
(
page 219).
iIf you do not take your foot off of the
accelerator completely, the following
message will appear in the multifunc-
tion display: DISTRONIC OVERRIDEDistronic will not work to maintain the
distance to a slower moving vehicles in
front of you. Your vehicle speed will
then be determined only by the accel-
erator pedal position.
iDepressing the accelerator pedal does
not deactivate Distronic. After brief ac-
celeration (e.g. for passing), the cruise
control resumes the last speed set.

224 Controls in detailDriving systemsDeactivating Distronic
There are several ways to deactivate the
Distronic system:
Briefly tip the cruise control lever in di-
rection of arrow3 (
page 221).
or

Step on the brake pedal.
Distronic will be deactivated. The last
speed set will be stored into memory.Distronic deactivates automatically when:


you set the parking brake


you drive slower than 22 mph
(35 km/h)


the ESP is active (
page 82) or you de-
activate the ESP


you move the gear selector lever into
positionN
A si gnal wi ll s ound. T he
DISTRONIC OFF

message appears in the multifunction
display for approximately five seconds.Setting the following distance in
Distronic
You can set the specified following dis-
tance for Distronic by varying the time set-
ting between 1.0 and 2.0 seconds. Using
this time setting and the current speed of
your vehicle, Distronic calculates and sets
the required following distance to the vehi-
cle ahead. The set distance will be shown
in the multifunction display field.
iThe following message will appear in
the multifunction display for approxi-
mately five seconds:
DISTRONIC OFF
.
The last stored speed is deleted when
you turn off the engine.
Warning!
G
Distronic switches off and releases the
brakes when the vehicle decelerates below
the minimum speed of approximately
22 mph (35 km/h) by operation of the sys-
tem. At that time the driver must apply the
brakes in order to reduce vehicle speed fur-
ther 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.

225 Controls in detail
Driving systems
The distance warning function on/off but-
ton and thumbwheel for setting distance
are located on the lower part of the front
center console.
1Distance warning function on/off but-
ton
2Thumbwheel for setting distanceIncreasing distance
Increasing the distance setting causes Dis-
tronic to maintain a greater following dis-
tance to the vehicle ahead.

Turn thumbwheel2 towards¯.
Decreasing distance
Decreasing the distance setting causes
Distronic to maintain a shorter following
distance to the vehicle ahead.

Turn thumbwheel2 towards®.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 the vehicle’s path and
the danger of a collision exists:


The distance warning lampl in the
instrument cluster comes on.


An intermittent warning sounds.
If these warnings are issued, you must
brake manually to maintain a safe distance
and avoid a collision with the vehicle
ahead.
When pressing the brake pedal, the warn-
ing sound stops. The warning sound also
stops when the distance to the vehicle
ahead is sufficient again without applying
the brake pedal. In this case the distance
warning lampl also extinguishes.

226 Controls in detailDriving systems
Activating
Press button1.
The indicator lamp on the button
comes on. A loudspeaker symbol ap-
pears in the multifunction display
(page 221).
Deactivating

Press button1.
The indicator lamp on the button goes
out.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 which will
deactivate the Distronic system.
Warning!
G
If the Distronic warning lampl in the in-
strument cluster 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 pos-
sible obstacle. However, do not drive by re-
lying on the distance warning function, as
this will result in an emergency braking ap-
plication. Especially depending on road sur-
face conditions 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.
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, then your vehicle could accelerate
to the previously selected speed.

227 Controls in detail
Driving systems
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
OPERATORS MANUAL
appears in the multi-
function display.
For cleaning and care of the Distronic sen-
sor, see “Cleaning the Distronic* system
sensor cover” (
page 333).Turns 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.
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.
iIf the message
DISTRONIC CURRENTLY
UNAVAILABLE SEE OPERATORS MANUAL
disappears during driving and the last
speed stored flashes for approximately
five seconds, the dirt (e.g. slush) has
dissolved; Distronic is again operation-
al.

235 Controls in detail
Driving systems
Parktronic system* (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 placed the gear selector lever in posi-
tion D, R, or N.
The Parktronic system deactivates at
speeds over approximately 11 mph
(18 km/h). At lower speeds the Parktronic
system turns on again.
The Parktronic system also deactivates
when you place the gear selector lever in
position P.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 333).
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.
Warning!
G
Make sure no persons or animals are in the
area in which you are maneuvering. You
could otherwise injure them.