MERCEDES-BENZ S CLASS 2003 Owners Manual

201 Controls in detail
Driving systems
Distronic displays in the speedometer
dialSet speedIf Distronic is activated, one or two seg-
ments light up around the set speed.
SegmentsIf Distronic detects a vehicle directly
ahead, the segments (representing the
difference) between the speed of the
vehicle ahead and the set speed light up.
If Distronic calculates that there is a dan-
ger of collision (
page 207):


The red Distronic warning lamp
l
in
the instrument cluster lights up.


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.
The intermittent warning sound ceases
and the red Distronic warning
lamp
l
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.

202 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 button
è
or
ÿ
repeatedly
until you see one of the following dis-
plays.
Warning!
G
An intermittent warning sounds and the
Distronic warning lamp
l
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.

203 Controls in detail
Driving systems
Distronic deactivated
If Distronic is deactivated, the standard
display of Distronic appears in the multi-
function display.
1Vehicle ahead, if detected
2Actual distance to vehicle ahead
3Should-be distance to vehicle ahead
4Symbol for activated distance warning
function
5Your vehicleDistronic activated
When you turn Distronic on, you will see
the set speed in the multifunction display
for about five seconds. If Distronic is
activated, you can see the following dis-
play in the multifunction display.
1Distronic activatedCruise 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 previously set speed

204 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 78)
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 or depress the cruise control
lever.
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 the
direction of arrow1 (
page 203) 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 multi-
function display for approximately five sec-
onds (
page 203), and one or two
segments around the stored speed light up
on the speedometer (
page 201).
iIf you do not take your foot off of the
accelerator completely, the following
message will appear in the multifunc-
tion display: DISTRONIC OVERRIDE
.
Distronic will not work to maintain the
distance to a slower moving vehicle 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 will resume the last speed set.

205 Controls in detail
Driving systems
Setting a lower speed
Briefly tip the cruise control lever in the
direction of arrow2 (
page 203) to
decrease vehicle speed in increments
of 5 mph (Canada: 10 km/h)
The new speed is set.
The stored speed is displayed in the multi-
function display for approximately five sec-
onds (
page 203), and one or two
segments around the stored speed light up
on the speedometer (
page 201).Fine adjustment in 1 mph
(Canada: 1 km/h) increments
Faster

Briefly tip the cruise control lever in the
direction of arrow4 (
page 203).Setting to last stored speed (“Resume”
function)

Briefly tip the cruise control lever in the
direction of arrow4 (
page 203).
Distronic is set to the last stored
speed.

Remove your foot from the accelerator
pedal.
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 preset
speed could cause an accident and/or seri-
ous injury you and others.

206 Controls in detailDriving systemsDeactivating Distronic
There are several ways to deactivate the
Distronic system:
Briefly tip the cruise control lever in the
direction of arrow3 (
page 203).
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
25 mph (40 km/h)


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


you move the transmission selector le-
ver into positionN
A signal will sound. The
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.
The thumbwheel for making the time set-
ting is located on the lower section of the
center console.
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
25 mph (40 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.

207 Controls in detail
Driving systems
1Distance warning function on/off
switch
2Thumbwheel for setting distanceIncreasing distance
Increasing the distance setting causes Dis-
tronic to maintain a greater following dis-
tance to the vehicle ahead.

Turn thumbwheel 2 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 lamp
l
in the
instrument cluster lights up.


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 lamp also extinguishes.
Warning!
G
I t is up t o t he d ri ver to exer c is e di s cr et io n 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.

208 Controls in detailDriving systems
Activating
Press switch1.
The indicator lamp on the switch lights
up. A loudspeaker symbol appears in
the multifunction display (
page 203).
Deactivating

Press switch1.
The indicator lamp on the switch 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 lamp
l
in the in-
strument cluster lights up 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.
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.


209 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 - CLEAN SENSOR! SEE
OPERATOR’S MAN.
appears in the multifunc-
tion display.
For cleaning and care of the Distronic sen-
sor, see “Cleaning the Distronic* system
sensor cover” (page 285).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 - CLEAN
SENSOR! SEE OPERATOR’S MAN.
disap-
pears during driving and the last speed
stored flashes for approximately five
seconds, the dirt (e.g. slush) has dis-
solved; Distronic is again operational.

210 Controls in detailDriving systemsOffset 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 lane-changing vehicle.Narrow vehicles
Because of its narrow profile, the vehicle
traveling near the edge of the roadway has
not yet been detected by Distronic. There
will be insufficient distance to the vehicle
ahead.