Page 235 of 491
234 Controls in detailDriving systemsDistronic displays in the speedometer
dial
1Set speed
If Distronic is activated, one or two seg-
ments come on around the set speed.1Segments
If 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:
The DTR warning lampl in the in-
strument cluster comes on red.
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 DTR warning lampl
goes out when the necessary distance
to the vehicle ahead is again estab-
lished.
iThe vehicle speed displayed on the
speedometer can briefly vary from the
speed setting on the Distronic system.
Page 236 of 491

235 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 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
DTR warning lampl in the instrument
cluster is illuminated if the Distronic system
calculates that the distance to the vehicle
ahead and your vehicle’s current speed indi-
cate 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 vehicle in front of you.
The warning sound is intended as a final cau-
tion that you have not interceded with your
own braking inputs to avoid a potentially
dangerous situation. Do not wait for the op-
eration 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 be-
ing avoided.
Tailgating increases the risk of an accident.
Warning!
G
Distronic brakes your vehicle with a maxi-
mum deceleration of 6.5 ft / s
2 (2 m / s
2).
This corresponds to about 20% of the maxi-
mum 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.
Page 237 of 491
236 Controls in detailDriving systemsDistronic deactivated
If Distronic is deactivated you can see the
standard display of Distronic in the multi-
function display.
1Vehicle ahead, if detected
2Actual distance to vehicle ahead
3Preset distance threshold to vehicle
ahead
4Your vehicle
5Symbol for activated distance warning
functionDistronic activated
If 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
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237 Controls in detail
Driving systems
Activating Distronic
You can activate Distronic if:
you are driving between 25 mph
(40km/h) and 110mph (180km/h)
the ESP is activated (
page 89)
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 236) to
increase 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 236), and one or
two segments around the stored speed
come on in the speedometer
(
page 234).
iIf you do not take your foot off the
accelerator completely, the following
message will appear in the multifunc-
tion display: Distronic override
. The distance to a
slower moving vehicles in front of you
will not be set. 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), cruise con-
trol will resume the last speed set.
Page 239 of 491

238 Controls in detailDriving systemsSetting a lower speed
Briefly tip the cruise control lever in the
direction of arrow2 (
page 236) 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
multifunction display for approximately
five seconds (
page 236), and one or
two segments around the stored speed
come on in the speedometer
(
page 234).Fine adjustment in 1 mph
(Canada: 1 km/h) increments
Faster
Briefly tip the cruise control lever in the
direction of arrow4 (
page 236).Setting stored speed
(“Resume” function)
Briefly tip the cruise control lever in the
direction of arrow4 (
page 236).
Distronic is activated and 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
automatically downshift if the rate of
deceleration 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 to you and others.
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239 Controls in detail
Driving systems
Deactivating Distronic
There are several ways to deactivate the
Distronic system:
Briefly tip the cruise control lever in the
direction of arrow3 (
page 236).
or
Step on the brake pedal.
Distronic will be deactivated. The last
speed set will be stored in memory.Distronic deactivates automatically when:
you set the parking brake
you drive slower than 25 mph
(40 km / h)
the ESP is active (
page 89) 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.
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.
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241 Controls in detail
Driving systems
Activating
Press button1.
Indicator lamp 2 on the button comes
on. A loudspeaker symbol appears in
the multifunction display (
page 236).
Deactivating
Press button1.
Indicator lamp 2 on the button goes
out. No loudspeaker symbol appears in
the multifunction display.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.
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.
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.
Page 243 of 491
242 Controls in detailDriving systemsThe 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,
Distronic will switch off, and the message Currently unavailable See Operator’s
Manual
appears in the multifunction
display.
For cleaning and care of the Distronic sen-
sor, see “Cleaning the Distronic* system
sensor cover” (
page 347).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.
iIf the message
Currently unavailable
See Operator’s Manual
disappears
during driving and the last speed stored
flashes for approximately five seconds,
the dirt (e.g. slush) has dissolved;
Distronic works again.