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Rthe ESP ®
has switched off due to a
malfunction
R you shift the automatic transmission into
neutral position N while driving
Observe additional messages in the
multifunction display that may appear.
Depressing the accelerator pedal does not
deactivate the cruise control. After a brief
acceleration (e.g. for passing), the cruise
control will resume the last set speed.
Changing the set speed GWarning!
Keep in mind that it may take a brief moment
until the vehicle has made the necessary
adjustments.
Increase or decrease the set vehicle speed to
a value that the prevailing road conditions and
legal speed limits permit. Otherwise, sudden
and unexpected acceleration or deceleration
of the vehicle could cause an accident and/
or serious injury to you and others.
You can increase or decrease the set speed
in 1 mph (Canada: 1 km/h) increments or in
5 mph (Canada: 10 km/h) increments.
When you use the cruise control lever to
decelerate, the brake system will brake the
vehicle automatically if the engine’s braking
power does not brake the vehicle sufficiently.
Adjustment in 1 mph (Canada:
1 km/h) increments
i The set speed value is increased or
decreased in 1 mph (Canada: 1 km/h)
increments each time you lift or press the
cruise control lever up or down to the
resistance point.
XIncreasing: Briefly lift the cruise control
lever up to the resistance point in direction
of arrow :.XDecreasing: Briefly press the cruise
control lever down to the resistance point
in direction of arrow ;.XRelease the cruise control lever.
The new speed is set and the vehicle will
accelerate or decelerate.
Adjustment in 5 mph (Canada:
10 km/h) increments
i The set speed value is increased or
decreased in 5 mph (Canada: 10 km/h)
increments each time you lift or press the
cruise control lever up or down past the
resistance point.
XIncreasing: Briefly lift the cruise control
lever up past the resistance point in
direction of arrow :.XDecreasing: Briefly press the cruise
control lever down past the resistance
point in direction of arrow ;.XRelease the cruise control lever.
The new speed is set and the vehicle will
accelerate or decelerate. Keep in mind that
it may take a brief moment until the vehicle
has reached the set speed.
Setting stored speed (Resume
function)
GWarning!
The set speed stored in memory should only
be set again if prevailing road conditions and
legal speed limits permit. Possible
acceleration or deceleration differences
arising from returning to the preset speed
could cause an accident and/or serious injury
to you and others.
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XBriefly pull the cruise control lever in
direction of arrow ?.
If no speed is stored, the current speed is
set and stored.XRemove your foot from the accelerator
pedal.
The last stored speed is deleted from memory
when the engine is turned off.
Distronic
Safety notes
When activated, the Distronic adaptive cruise
control increases the driving convenience
afforded by the cruise control while traveling
on expressways and other major roadways.
R If the Distronic distance sensor detects a
slower moving vehicle directly ahead, your
vehicle speed will be reduced so that you
follow that vehicle at your preset following
distance.
R If there is no vehicle directly ahead of you,
the Distronic will function in the same way
as standard cruise control ( Y page 141).
GWarning!
The Distronic requires familiarity with its
operational characteristics. We strongly
recommend that you review the following
information carefully before operating the
system.
GWarning!
HYBRID vehicles: It is imperative that you read
the HYBRID Supplemental Operating
Instructions included in your vehicle literature
portfolio. You may otherwise not recognize
potential danger.
GWarning!
When the Distronic is braking, the brake pedal
is retracted (i.e. depressed automatically).
The pedals’ range of motion must not be
impeded by any obstacles:
R Do not place any objects in the footwell.
R Make sure that the floormats and carpets
are securely in place.
R Do not rest your foot underneath the brake
pedal, as it could otherwise be trapped.
You could otherwise cause an accident and
injure yourself and/or others.
GWarning!
The Distronic is a convenience system. Its
speed adjustment reduction capability is
intended to make cruise control more
effective and usable when traffic speeds vary.
It is not however, intended to, nor does it,
replace the need for extreme care.
The responsibility for the vehicle’s speed,
distance to the preceding vehicle and, most
importantly, brake operation to ensure a safe
stopping distance, always remains with the
driver.
The Distronic cannot take street and traffic
conditions into account. Complex driving
situations are not always fully recognized by
the Distronic. This could result in wrong or
missing distance warnings.
GWarning!
The Distronic adaptive cruise control is not a
substitute for active driving involvement. It
does not react to pedestrians or on stationary
objects, nor does it recognize or predict the
lane curvature or the movement of preceding
vehicles.
The Distronic can only apply 20% of the
maximum braking power of the vehicle.
It is the driver’s responsibility at all times to
be attentive to the road, weather and traffic
conditions. Additionally, the driver must
provide the steering, braking and other driving
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inputs necessary to remain in control of the
vehicle.
High-frequency sources such as toll stations,
speed measuring systems etc. can cause the
Distronic system to malfunction.GWarning!
The Distronic cannot take road and traffic
conditions into account. Only use the
Distronic if the road, weather and traffic
conditions make it advisable to travel at a
constant speed.
GWarning!
Use of the Distronic can be dangerous on
slippery roads. Rapid changes in tire traction
can result in wheel spin and loss of control.
The Distronic does not function in adverse
sight and distance conditions. Do not use the
Distronic during conditions of fog, heavy rain,
snow or sleet.
GWarning!
The Distronic cannot take weather conditions
into account. Switch off the Distronic or do
not switch it on if:
R roads are slippery or covered with snow or
ice. The wheels could lose traction while
braking or accelerating, and the vehicle
could skid.
R the Distronic system sensor cover is dirty
or visibility is diminished due to snow, rain
or fog, for example. The distance control
system functionality could be impaired.
Always pay attention to surrounding traffic
conditions even while the Distronic is
switched on. Otherwise, you may not be able
to recognize dangerous situations until it is
too late. This could cause an accident in which
you and/or others could be injured.
GWarning!
The “Resume” function should only be
operated if the driver is fully aware of the
previously set speed and wishes to resume
this particular preset speed.GWarning!
Close attention to road and traffic conditions
is imperative at all times, regardless of
whether or not the Distronic is activated.
Use of the Distronic can be dangerous on
winding roads or in heavy traffic because
conditions do not allow safe driving at a
constant speed.
The Distronic will not react to stationary
objects in the roadway (e.g. a stopped vehicle
in a traffic jam or a disabled vehicle). The
Distronic will also not respond to oncoming
vehicles.
Switch off the Distronic:
R when changing from the left to the right
lane if vehicles are moving more slowly in
the left lane
R when entering a turn lane or highway off
ramp
R in complex driving situations, such as in
highway construction zones
In these situations, the Distronic will continue
to maintain the set speed unless deactivated.
The Distronic is designed and intended only
to maintain a set speed and keep a set
distance from moving objects in front of it.
i This device has been approved by the FCC
as a “Vehicular Radar System”. The radar
sensor is intended for use in an automotive
radar system only. Removal, tampering, or
altering of the device will void any
warranties, and is not permitted by the
FCC. Do not tamper with, alter, or use in
any non-approved way.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
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Distronic displays in the speedometer
When the Distronic is activated, one or two
cruise control speed segments come on
around set speed :.
The vehicle speed displayed on the
speedometer can briefly vary from the speed
setting on the Distronic system.
When the Distronic detects a vehicle directly
ahead, the cruise control speed
segments ; appear in the speedometer.
These segments represent the difference
between the set speed of your vehicle : and
the speed of the preceding vehicle =.
If the Distronic calculates that there is a
danger of collision, the distance warning lamp
· in the instrument cluster comes on and
an intermittent warning sounds.
XImmediately apply the brakes to avoid a
collision.
Under no circumstances should the driver
await the intermittent warning sound
before braking.
The intermittent warning sound ceases and
the distance warning lamp · goes out
when the necessary distance to the vehicle
ahead is established again.
GWarning!
An intermittent warning sounds and the
distance warning lamp · in the instrument
cluster is illuminated if the Distronic system
calculates that the distance to the vehicle
ahead and your vehicle’s current speed
indicate that the 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
your distance to the preceding vehicle. The
warning sound is intended as a final caution
in which you should intercede with your own
braking inputs to avoid a potentially
dangerous situation. Do not wait for the
operation of the warning signal to intercede
with your own braking. This will result in
potentially dangerous emergency braking
which will not always result in an impact being
avoided.
Tailgating increases the risk of an accident.
GWarning!
The Distronic brakes your vehicle with a
maximum deceleration of 6.5 ft/s2 (2 m/s2).
This corresponds to approximately 20% of the
maximum deceleration of your vehicle.
You must also apply the brakes yourself to
avoid a collision. The Distronic brakes the
vehicle in an effort to restore the preset
distance or to maintain the set 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,
including the area under the brake pedal.
Objects 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.
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Distronic menu in the control system
Use the DISTRONIC menu to display the
current settings for your Distronic system.
The information shown in the multifunction
display depends on whether the Distronic
system and/or the distance warning function
are activated or deactivated.
iTo activate or deactivate the Distronic
system, see (Y page 147) or see
(Y page 149).
To activate or deactivate the Distance
warning function, see (Y page 137).
XPress button V or U repeatedly until
one of the following two displays appears
in the multifunction display.
Distronic deactivated
When the Distronic is deactivated, you will
see the standard Distronic display in the
multifunction display.
:Preceding vehicle, if detected;Actual distance to the preceding vehicle=Preset distance threshold to the
preceding vehicle
?Your vehicle
Distronic activated
When the Distronic is activated :, you will
see the set speed ; in the multifunction
display for approximately 5 seconds. The
following display appears in the multifunction
display.
After approximately 5 seconds the currently
set speed ; appears in the status indicator
of the multifunction display:
DTR XXX Miles
Cruise control lever
The Distronic system is operated by means of
the cruise control lever.
:Setting current or higher speed;Setting current or lower speed=Deactivating the Distronic?Activating the Distronic or resuming to
the last set speed
Activating Distronic
You can activate the Distronic when the
vehicle speed is between 20 mph (30 km/h)
and 110 mph (180 km/h).
When the Distronic is activated, one or two
cruise control speed segments around the set
speed in the speedometer dial are
illuminated. The multifunction display will
show a message such as
DISTRONIC 55 MPH
(Canada: DISTRONIC 90 km/h).
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After approximately 5 seconds the currently
set speed appears in the status indicator of
the multifunction display:
R USA only: e.g. DTR 55 Miles
R Canada only: e.g. DTR 90 km/h
If the Distronic is not activated after the
cruise control lever is pulled in direction of
arrow ? (Y page 147), you will see the
message DISTRONIC Off in the
multifunction display.
In the following cases you cannot activate the
Distronic:
R up to 2 minutes after starting the engine
R when you brake
R when you have engaged the parking brake
R when the automatic transmission is in park
position P, reverse gear R, or neutral
position N
R when the ESP ®
is switched off or has
switched off due to a malfunction
The vehicle speed displayed on the
speedometer can briefly vary from the speed
setting on the Distronic system.
Setting the current speedXAccelerate or decelerate to the desired
speed.XBriefly lift the cruise control lever in
direction of arrow : or depress in
direction of arrow ; (Y page 147).XRemove your foot from the accelerator
pedal.
i If you do not take your foot off of the
accelerator pedal and continue to
accelerate past the set speed, the following
message will appear in the multifunction
display:
DISTRONIC Override
The distance to a slower moving vehicle in
front of you will not be set. Your vehicle
speed will then be determined only by the
accelerator pedal position.
Changing the set speedGWarning!
Keep in mind that it may take a brief moment
until the vehicle has made the necessary
adjustments.
Increase or decrease the set vehicle speed to
a value that the prevailing road conditions and
legal speed limits permit. Otherwise, sudden
and unexpected acceleration or deceleration
of the vehicle could cause an accident and/
or serious injury to you and others.
You can increase or decrease the set speed
in 1 mph (Canada: 1 km/h) increments or in
5 mph (Canada: 10 km/h) increments.
When you use the cruise control lever to
decelerate, the brake system will brake the
vehicle automatically if the engine’s braking
power does not brake the vehicle sufficiently.
Adjustment in 1 mph (Canada:
1 km/h) increments
i The set speed value is increased or
decreased in 1 mph (Canada: 1 km/h)
increments each time you lift or press the
cruise control lever up or down to the
resistance point.
XIncreasing: Briefly lift the cruise control
lever up to the resistance point in direction
of arrow : (Y page 147).XDecreasing: Briefly press the cruise
control lever down to the resistance point
in direction of arrow ; (Y page 147).XRelease the cruise control lever.
The new speed is set and the vehicle will
accelerate or decelerate.
Adjustment in 5 mph (Canada:
10 km/h) increments
i The set speed value is increased or
decreased in 5 mph (Canada: 10 km/h)
increments each time you lift or press the
cruise control lever up or down past the
resistance point.
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XIncreasing: Briefly lift the cruise control
lever up past the resistance point in
direction of arrow : (Y page 147).XDecreasing: Briefly press the cruise
control lever down past the resistance
point in direction of arrow ;
( Y page 147).XRelease the cruise control lever.
The new speed is set and the vehicle will
accelerate or decelerate. Keep in mind that
it may take a brief moment until the vehicle
has reached the set speed.
Setting stored speed (Resume function)
GWarning!
The set speed stored in memory should only
be set again if prevailing road conditions and
legal speed limits permit. Possible
acceleration or deceleration differences
arising from returning to the preset speed
could cause an accident and/or serious injury
to you and others.
XBriefly pull the cruise control lever in
direction of arrow ? (Y page 147).
If no speed is stored, the current speed is
set and stored.XRemove your foot from the accelerator
pedal.
Deactivating Distronic
XDepress the brake pedal.
or
XBriefly push the cruise control lever in
direction of arrow = (Y page 147).
The cruise control speed segments in the
speedometer dial will go out and the
following message appears briefly in the
multifunction display: DISTRONIC Off
The last set speed is stored for later use.
The last stored speed is deleted from memory
when the engine is turned off.
The Distronic switches off automatically
when you depress the brake pedal or you
engage the parking brake. In this case, the
cruise control speed segments in the
speedometer dial will go out.
The Distronic also switches off automatically
when
R the vehicle speed falls below 20 mph
(30 km/h)
R the ESP ®
is in operation
R the ESP ®
is switched off with the ESP ®
switch
R the ESP ®
has switched off due to a
malfunction
R you shift the automatic transmission into
neutral position N while driving
The cruise control speed segments in the
speedometer dial goes out and an acoustic
warning will sound. Observe additional
messages in the multifunction display that
may appear.GWarning!
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.
Depressing the accelerator pedal does not
deactivate the Distronic. After a brief
acceleration (e.g. for passing), the Distronic
will resume the last set speed.
Setting the following distance in
Distronic
You can set the specified following distance
for Distronic by varying the time setting
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 preceding vehicle.
The set distance will be shown in the
multifunction display.
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GWarning!
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
recommendations for safe following distance.
XIncreasing distance: Turn distance
setting switch : in direction of arrow =.
Increasing the distance setting tells
Distronic to maintain a greater following
distance to the preceding vehicle.
XDecreasing distance: Turn distance
setting switch : in direction of arrow ;.
Decreasing the distance setting tells
Distronic to maintain a shorter following
distance to the preceding vehicle.
Driving with Distronic
This section describes a number of driving
situations where special precaution is
required on the part of the driver. Be prepared
to brake in such situations. Braking will
deactivate the Distronic system.
GWarning!
The Distronic works to maintain the speed
selected by the driver unless a moving
obstacle proceeding directly ahead of it in the
same travel direction is detected (e.g.
following another vehicle ahead of you at your
set distance).
This means that:
RYour vehicle can pass another vehicle after
you have changed lanes.
RWhile in a sharp turn or if the preceding
vehicle is in a sharp turn, the Distronic
could lose sight of the preceding vehicle.
Your vehicle could then accelerate to the
previously selected speed.
The Distronic regulates only the distance
between your vehicle and those directly
ahead of it, but does not register stationary
objects in the road, e.g.:
Ra stopped vehicle in a traffic jam
Ra disabled vehicle
Ran oncoming vehicle
The driver must always be alert, observe all
traffic and intercede as required by means of
steering or braking the vehicle.
GWarning!
The Distronic should not be used in snowy or
icy road conditions.
The most likely cause for a malfunctioning
system is a dirty Distronic system sensor
cover (located in the hood grille), especially
at times of snow and ice or heavy rain.
In such a case, the Distronic will switch off,
and the message DISTRONIC Currently
Unavailable – See Operator’s Manual
appears in the multifunction display.
For cleaning and care of the Distronic system
sensor cover, see (Y page 263).
iIf the message DISTRONIC Available
Again appears during driving, the dirt (e.g.
slush) has dissolved; the Distronic works
again, if you reactivate it (Y page 147).
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