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:Preceding vehicle, if detected;Actual distance to the preceding vehicle=Preset distance threshold to the
preceding vehicle
?Your vehicle
DISTRONIC PLUS lever
:Setting current or higher speed;Setting current or lower speed=Deactivating the DISTRONIC PLUS?Activating the DISTRONIC PLUS or
resuming to the last set speed
ASetting following distance
Activating DISTRONIC PLUS
GWarning!
When the DISTRONIC PLUS is switched on,
the vehicle can be braked. You should
therefore switch off the DISTRONIC PLUS if
the vehicle must be towed.
You can activate the DISTRONIC PLUS when
the vehicle speed is above 20 mph
(30 km/h).
It is also possible to activate the DISTRONIC
PLUS when the vehicle speed is below
20 mph (30 km/h) and the DISTRONIC PLUS
has detected a preceding vehicle.
If the DISTRONIC PLUS is activated, the set
speed is indicated with marker ;
(Y page 333) in the speedometer dial.
The maximum vehicle speed you can set is
120 mph (Canada: 200 km/h).
If the DISTRONIC PLUS is not activated after
the DISTRONIC PLUS lever is pulled in
direction of arrow ? (Y page 335), you will
see the message: DISTRONIC PLUS ---
mph (Canada: DISTRONIC PLUS --- kmh) in
the multifunction display.
In the following cases you cannot activate the
DISTRONIC PLUS:
Rwithin 2 minutes after driving off, following
an engine start
Rif the vehicle is secured with the electronic
parking brake
Rif the ESC is switched off or has switched
off due to a malfunction
Rwhen the automatic transmission is in park
position P, reverse gear R, or neutral
position N
Rif the hood is open
Rif the driver’s door is open and the driver
has not fastened his or her seat belt
Rif the front passenger or a rear passenger
door is open
Rif the radar sensors are switched off
(Y page 236)
Switching on while driving
You can switch on the DISTRONIC PLUS when
the vehicle speed is above 20 mph
(30 km/h).
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Below 20 mph (30 km/h), you can only switch
on the DISTRONIC PLUS if the preceding
vehicle has been detected and is shown in the
multifunction display. If you no longer see the
preceding vehicle in the multifunction display
and if it is no longer detected because it has
changed lanes, for example, the DISTRONIC
PLUS switches off and a signal sounds.XPull the DISTRONIC PLUS lever briefly in
direction of arrow ? to call up the last set
speed, or if no speed is stored, to set and
store the current speed.
The DISTRONIC PLUS is switched on.
or
XTap the DISTRONIC PLUS lever up : or
down ; until desired speed is set.
The DISTRONIC PLUS is switched on.XRemove your foot from the accelerator
pedal.
Your vehicle adapts its speed to the
preceding vehicle, observing the set speed
as a maximum value.
If you do not completely remove your foot
from the accelerator pedal, the message
DISTRONIC PLUS Override appears in the
multifunction display. The distance to a
slower-driving vehicle will not be set. You will
drive at the speed you dictate by pressing the
accelerator pedal.
Switching on when approaching a
stationary vehicle
It is helpful to switch on the DISTRONIC PLUS
display in the multifunction display to see that
a preceding vehicle is detected
( Y page 334). You can only switch on the
DISTRONIC PLUS below a speed of 20 mph
(30 km/h) when a preceding vehicle is
detected.
If the preceding vehicle is stationary, you can
only switch on the DISTRONIC PLUS if your
vehicle is also at a standstill.
XPull the DISTRONIC PLUS lever briefly in
direction of arrow ?.
The DISTRONIC PLUS is switched on.XTap the DISTRONIC PLUS lever up : or
down ; until desired speed is set.
You can adjust the set speed using the
DISTRONIC PLUS lever and the target
distance using the distance setting switch on
the DISTRONIC PLUS lever ( Y page 339).
i If the DISTRONIC PLUS is switched off,
the PRE-SAFE ®
Brake (Y page 69) will warn
of an impending collision if this function has
been activated with the instrument cluster
control system ( Y page 232).
Starting off
When the preceding vehicle starts off:
XRemove your foot from the brake pedal.XPull the DISTRONIC PLUS lever briefly in
direction of arrow ?.
or
XBriefly step on the accelerator pedal.
Your vehicle starts off and adapts its speed
to the preceding vehicle.
Driving
If there is no preceding vehicle, the
DISTRONIC PLUS functions like the cruise
control ( Y page 328).
When the DISTRONIC PLUS detects that the
preceding vehicle is driving more slowly, it
brakes the vehicle in order to keep the
distance specified by you.
When the DISTRONIC PLUS detects that the
preceding vehicle is driving faster, it
accelerates the vehicle up to the set speed.
GWarning!
When you step on the brake pedal, you switch
off the DISTRONIC PLUS except when the
vehicle is at a standstill. The DISTRONIC PLUS
will no longer brake your vehicle. You are
always responsible for maintaining a distance
from other vehicles, observing road speeds
and braking well in advance.
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StoppingGWarning!
The braking effect of the DISTRONIC PLUS is
canceled and the vehicle can start to roll if
R the DISTRONIC PLUS is switched off using
the DISTRONIC PLUS lever
R you accelerate
R the DISTRONIC PLUS system or the power
supply is malfunctioning, e.g. due to battery
failure
R the electrical components in the engine
compartment or the fuses have been
manipulated
R the battery is disconnected
GWarning!
Never get out of the vehicle while the
DISTRONIC PLUS is switched on!
The DISTRONIC PLUS must never be operated
or switched off by passengers or from outside
the vehicle.
The DISTRONIC PLUS is not a substitute for
the electronic parking brake. It must not be
used to secure the vehicle when parking.
When you get out of the vehicle or switch off
the engine, deactivate the DISTRONIC PLUS
and secure the vehicle from rolling away by
engaging the electronic parking brake.
When the DISTRONIC PLUS detects that the
preceding vehicle is stopping, the vehicle
brakes until it also stops. Once the vehicle is
at a standstill, it remains stationary, without
depressing the brake pedal.
After a short while, the vehicle is secured in
place by the electronic parking brake so that
the operating brake can be relieved of load.
Depending on the following distance set
using the distance setting switch on the
DISTRONIC PLUS lever ( Y page 339), the
vehicle will stop adequate away from the
preceding vehicle.
When the DISTRONIC PLUS is activated and
the vehicle is at a standstill, the automatic
transmission shifts into park position P
automatically when
R opening the driver’s door and releasing the
seat belt
R turning off the engine
R opening the hood
R a system malfunction occurs
R the on-board voltage is insufficient
The DISTRONIC PLUS is deactivated.
Setting the current speedXAccelerate or decelerate to the desired
speed.XBriefly lift the DISTRONIC PLUS lever in
direction of arrow : or depress in
direction of arrow ; (Y page 335).
The current speed is set.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 PLUS 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 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.
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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 DISTRONIC PLUS 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
DISTRONIC PLUS lever up or down to the
resistance point.XIncreasing: Briefly lift the DISTRONIC
PLUS lever up to the resistance point in
direction of arrow :.XDecreasing: Briefly press the DISTRONIC
PLUS lever down to the resistance point in
direction of arrow ;.XRelease the DISTRONIC PLUS 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
DISTRONIC PLUS lever up or down past the
resistance point.
XIncreasing: Briefly lift the DISTRONIC
PLUS lever up past the resistance point in
direction of arrow :.XDecreasing: Briefly press the DISTRONIC
PLUS lever down past the resistance point
in direction of arrow ;.XRelease the DISTRONIC PLUS 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 DISTRONIC PLUS lever in
direction of arrow ? (Y page 335).
The DISTRONIC PLUS is activated and
resumes to the last set speed or, if no
speed is stored, it will set and store the
current speed.XRemove your foot from the accelerator
pedal.
Deactivating DISTRONIC PLUS
XDepress the brake pedal (only possible if
the vehicle is in motion).
or
XBriefly push the DISTRONIC PLUS lever in
direction of arrow = (Y page 335).
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 PLUS switches off
automatically when
R the vehicle is secured with the electronic
parking brake
R the vehicle speed falls below 15 mph
(25 km/h) and no preceding vehicle is
detected
R the ESC is in operation, or switched off via
the control system (Y page 232), or the ESC
has switched off due to a malfunction
R you shift the automatic transmission into
park position P, reverse gear R, or neutral
position N while driving
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Rthe radar sensors are switched off
Ryou pull the DISTRONIC PLUS lever in
direction of arrow ? (Y page 335) for
driving off and the front passenger or a rear
passenger door is open
The marker for the set speed on the
speedometer dial go out, an acoustic signal
sounds, and the message DISTRONIC PLUS
Off appears in the multifunction display for
approximately 5 seconds.
GWarning!
The DISTRONIC PLUS 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
unless the DISTRONIC PLUS detects a vehicle
directly ahead of you. 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 PLUS. After a brief
acceleration (e.g. for passing), the
DISTRONIC PLUS will resume the last set
speed.
Setting the following distance in
DISTRONIC PLUS
You can set the specified following distance
for the DISTRONIC PLUS by varying the time
setting between 1.0 and 2.0 seconds. Using
this time setting and the current speed of
your vehicle, the DISTRONIC PLUS calculates
and sets the required following distance to
the preceding vehicle.
The set distance will be shown in the
multifunction display.
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 the
DISTRONIC PLUS 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 the
DISTRONIC PLUS to maintain a shorter
following distance to the preceding vehicle.
Driving with DISTRONIC PLUS
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 PLUS system.
GWarning!
The DISTRONIC PLUS 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
PLUS could lose sight of the preceding
vehicle. Your vehicle could then accelerate
to the previously selected speed.
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The DISTRONIC PLUS regulates only the
distance between your vehicle and those
directly ahead of it. It may 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 PLUS should not be used in
snowy or icy road conditions.
The most likely cause for a malfunctioning
system is a dirty sensor (located in the hood
grille and in the bumper), especially at times
of snow and ice or heavy rain.
In such a case, the DISTRONIC PLUS will
switch off, and the message DISTRONIC
PLUS Currently Unavailable See
Oper. Manual appears in the multifunction
display.
For cleaning and care of the sensors, see
(Y page 443).
iIf the message DISTRONIC PLUS
Currently Unavailable See Oper.
Manual disappears during driving and the
last speed stored flashes for approximately
5 seconds, the dirt (e.g. slush) has
dissolved; the DISTRONIC PLUS is available
again.
Another cause might be that the radar
sensors have been manually switched off in
the instrument cluster control system. Please
verify that the radar sensors are switched on
(Y page 236).
Turns and bends
In turns or bends, the DISTRONIC PLUS may
not detect a preceding vehicle, 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 the DISTRONIC PLUS. There will be
insufficient distance to the preceding vehicle.
Lane changing
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The DISTRONIC PLUS has not yet detected
the vehicle changing lanes. There will be
insufficient distance to the lane-changing
vehicle.
Narrow vehicles
Because of their narrow profile, the vehicles
traveling near the outer edges of the lane
have not yet been detected by the DISTRONIC
PLUS. There will be insufficient distance to
the preceding vehicles.
Obstacles and stationary vehicles
The DISTRONIC PLUS does not brake for
obstacles or stationary vehicles. If, for
example, the vehicle detected in front of you
changes lanes to bypass an obstacle or
stationary vehicle in front of it, the
DISTRONIC PLUS will not brake for the
obstacle or stationary vehicle.
Cross-traffic
The DISTRONIC PLUS may inadvertently
detect crossing vehicles. If you switch on the
DISTRONIC PLUS, for example, at a traffic
light with cross traffic, the vehicle may
suddenly start to drive off.
Hill-start assist system
On uphill grades, the hill-start assist system
maintains the pressure in the brake system
for approximately 1 second after you have
released the brake pedal. Therefore, you can
start off smoothly without the vehicle moving
immediately after releasing the brake pedal.
GWarning!
The hill-start assist system is not designed to
function as a parking brake. It does not
prevent the vehicle from moving when parked
on an incline.
Always engage the electronic parking brake
in addition to shifting the automatic
transmission into park position P.
The hill-start assist system is inactive
Rwhen starting off on a level road or downhill
grades
Rwith the automatic transmission in neutral
position N
Rwith the electronic parking brake engaged
Rif the ESC has switched off due to a
malfunction
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HOLD function
The HOLD function can assist you
Rwhen driving off, especially on steep slopes
Rwhen maneuvering on steep slopes
Rwhen waiting in traffic
The vehicle is kept stationary without the
driver having to depress the brake pedal.
Upon depressing the accelerator pedal, the
braking effect is canceled and the HOLD
function is deactivated.
GWarning!
HYBRID vehicles: It is imperative that you read
the HYBRID Supplemental Operating
Instructions included in your vehicle literature
portfolio. You may otherwise not receive all
necessary safety information and warning for
the operation of your vehicle.
Activation conditions
You can activate the HOLD function when
Rthe vehicle is stationary
Rthe engine is running
Ryour seat belt is fastened or the driver’s
door is closed
Rthe electronic parking brake is released
Rthe hood is closed
Rthe automatic transmission is in neutral
position N, drive position D, or reverse gear
R
When the automatic transmission is in
reverse gear R, the trunk lid must be
closed.
Rthe DISTRONIC PLUS is deactivated
(Y page 338).
Activating HOLD XMake sure the activation conditions are
met.
XDepress the brake pedal.XContinue to depress the brake pedal with
increased pedal pressure until the message
HOLD appears in the multifunction display.
The HOLD function is activated. You can
now release the brake pedal.
HOLD function activated
iThe brake pedal does not return to the
rest position completely while the HOLD
function is activated.
iIf the HOLD function is not activated when
depressing the brake pedal, wait briefly and
repeat the above steps.
GWarning!
The vehicle’s brakes are applied when the
HOLD function is activated. Therefore,
deactivate the HOLD function, for example,
when the vehicle is pulled through an
automatic car wash or being towed.
Deactivating HOLD
The HOLD function is switched off when
Ryou depress the accelerator pedal with the
automatic transmission in drive position D
or reverse gear R
Ryou shift the automatic transmission into
park position P
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