420 Controls in detail
Driving systems
StoppingWhen DISTRONIC Plus detects that the ve-
hicle in front of you is stopping, the vehicle
brakes until it also stops.
Once DISTRONIC Plus has stopped your
vehicle and it is at a standstill, it remains
stationary; the brake pedal does not need
to be depressed.
Warning!G
DISTRONIC Plus’s braking effect is canceled
and the vehicle can start to roll if
DISTRONIC Plus is switched off using
the DISTRONIC Plus lever
you accelerate
the system or the power supply is mal-
functioning, e.g. due to battery failure
the electrical components in the engine
compartment or the fuses have been
manipulated
the battery is disconnected
Warning!G
Never get out of the vehicle while
DISTRONIC Plus is switched on!
DISTRONIC Plus must never be operated or
switched off by passengers or from outside
the vehicle.
DISTRONIC Plus is not a substitute for the
electronic parking brake and may not be
used for parking.
When you get out of the vehicle or switch off
the engine, deactivate DISTRONIC Plus and
secure the vehicle from rolling away by en-
gaging the electronic parking brake.
iAfter a short while, your vehicle is secured in
place by the electronic parking brake so that the
operating brake can be relieved of load.
iDepending on the following distance set us-
ing the distance setting switch on the DISTRON-
IC Plus lever, your vehicle will stop
approximately 13.1 ft away from the vehicle in
front of you.
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422 Controls in detail
Driving systems
Adjustment in 5 mph
(Canada: 10 km/h) increments
Briefly lift the DISTRONIC Plus lever up
past the resistance point in direction of
arrow1 (
page 416).
Release the DISTRONIC Plus lever.
The vehicle speed increases in incre-
ments of 5 mph (Canada: 10 km/h).Setting a lower speed
You can reduce the speed in two ways.Adjustment in 1 mph (Canada: 1 km/h)
increments
Briefly press the DISTRONIC Plus lever
down to the resistance point in direc-
tion of arrow2 (
page 416).
Release the DISTRONIC Plus lever.
The vehicle speed decreases in incre-
ments of 1 mph (Canada: 1 km/h).
iThe set speed value is increased in 5 mph
(Canada: 10 km/h) increments each time you
lift the DISTRONIC Plus lever up past the resis-
tance point.
iThe new speed is set and the vehicle will ac-
celerate. Keep in mind that it may take a brief
moment until the vehicle has reached the set
speed.
Warning!G
If you decrease the set speed, keep in mind
that it may take a brief moment until the ve-
hicle has reached the set speed.
Decelerate the set speed to a value that the
prevailing road conditions and legal speed
limits permit. Otherwise, sudden and unex-
pected deceleration of the vehicle could
cause an accident and/or serious injury to
you and others.
iWhen you use the DISTRONIC Plus lever to
decelerate, the brake system will automatically
brake the vehicle if the engine’s braking power
does not brake the vehicle sufficiently.
iThe set speed value is decreased in 1 mph
(Canada: 1 km/h) increments each time you
press the DISTRONIC Plus lever down to the re-
sistance point.
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423 Controls in detail
Driving systems
Adjustment in 5 mph
(Canada: 10 km/h) increments
Briefly press the DISTRONIC Plus lever
down past the resistance point in
direction of arrow2 (
page 416).
Release the DISTRONIC Plus lever.
The vehicle speed decreases in incre-
ments of 5 mph (Canada: 10 km/h).Setting to last stored speed (“Resume”
function)
Briefly pull the DISTRONIC Plus lever in
direction of arrow4 (
page 416).
The DISTRONIC Plus resumes to the
last set speed, or if no speed is stored,
it will set and store the current speed.
Remove your foot from the accelerator
pedal.Deactivating DISTRONIC Plus
There are several ways to deactivate the
DISTRONIC Plus system:
Briefly tip the DISTRONIC Plus lever in
the direction of arrow3 (
page 416).
or
Step on the brake pedal.
DISTRONIC Plus will be deactivated.
The last speed set will be stored into
memory.
iThe set speed value is decreased in 5 mph
(Canada: 10 km/h) increments each time you
press the DISTRONIC Plus lever down past the
resistance point.
iThe new speed is set and the vehicle will de-
celerate. Keep in mind that it may take a brief
moment until the vehicle has reached the set
speed.
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.
iUpon switching off the engine, the last
stored speed is deleted.
iThe last stored set speed is deleted when
the engine is turned off.
ProCarManuals.com
424 Controls in detail
Driving systems
DISTRONIC Plus deactivates automatically
when:
the vehicle is secured with the elec-
tronic parking brake
the vehicle speed is below 20 mph
(30 km/h) and no preceding vehicle is
detected
the ESP® is in operation or switched off
with the ESP® switch (page 71)
you set the automatic transmission
toP, R, or N while driving
the radar sensors are switched off
(
page 272)
the vehicle rolls backward
The segments in the multifunction display
go out, an acoustic signal sounds, and the
message “DISTRONIC PLUS Off” appears in
the multifunction display for approximately
5 seconds.If the vehicle has been stopped by
DISTRONIC Plus and a malfunction occurs
in the system, the message “Brake immedi-
ately” will appear on the multifunction dis-
play. Step on the brake immediately to
prevent the vehicle from rolling.
DISTRONIC Plus is then switched off and
the message disappears.
Warning!G
DISTRONIC Plus switches off and releases
the brakes when the vehicle decelerates be-
low the minimum speed of 20 mph
(30 km/h) by operation of the system un-
less DISTRONIC Plus detects a vehicle di-
rectly ahead of you. At that time the driver
must apply the brakes in order to reduce ve-
hicle speed further or bring it to a stop.
!Setting the automatic transmission toN
while driving cancels the DISTRONIC Plus. How-
ever, the automatic transmission should not be
set toN while driving except to coast when the
vehicle is in danger of skidding (e.g. on icy
roads).
iDepressing the accelerator pedal does not
deactivate DISTRONIC Plus. After brief accelera-
tion (e.g. for passing), DISTRONIC Plus will re-
sume to the last set speed.
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426 Controls in detail
Driving systems
Driving with DISTRONIC Plus
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. Braking
will deactivate the DISTRONIC Plus sys-
tem.
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,
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
DISTRONIC Plus sensor, see “Cleaning the
DISTRONIC Plus*/ PRE-SAFE
® Brake* sys-
tem sensors (USA only)”(
page 558).
Another cause might be that the radar sen-
sors have been manually switched off in
the instrument cluster control system.
Please verify that the radar sensors are
switched on (
page 272).
Warning!G
DISTRONIC Plus works to maintain the
speed selected by the driver unless a mov-
ing 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:
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 Plus
could lose sight of a vehicle traveling in
front of it, then your vehicle could accel-
erate to the previously selected speed.
DISTRONIC Plus regulates only the distance
between your vehicle and those directly
ahead of it. It may not register stationary ob-
jects in the road, e.g.:
a stopped vehicle in a traffic jam
a disabled vehicle
an oncoming vehicle
The driver must always be alert, observe all
traffic and intercede as required by means
of steering or braking the vehicle.
Warning!G
DISTRONIC Plus should not be used in
snowy or icy road conditions.
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; DISTRONIC Plus is
available again.
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427 Controls in detail
Driving systems
Turns and bends
In turns or bends, DISTRONIC Plus 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.Offset driving
A vehicle traveling in your lane but offset
from your direct line of travel may not be
detected by DISTRONIC Plus. There will be
insufficient distance to the vehicle ahead.Lane changing
DISTRONIC Plus has not yet detected the
vehicle changing lanes. There will be insuf-
ficient distance to the lane-changing vehi-
cle.
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428 Controls in detail
Driving systems
Narrow vehicles
Because of their narrow profile, the vehi-
cles traveling near the outer edge of the
lane have not yet been detected by
DISTRONIC Plus. There will be insufficient
distance to the vehicles ahead.Obstacles and stationary vehicles
DISTRONIC Plus does not brake for obsta-
cles or stationary vehicles. If, for example,
the vehicle detected in front of you chang-
es lanes to bypass an obstacle or station-
ary vehicle in front of it, DISTRONIC Plus
will not brake for the obstacle or stationary
vehicle.Cross-traffic
DISTRONIC Plus may inadvertently detect
crossing vehicles. If you switch on DIS-
TRONIC Plus, for example, at a traffic light
with cross-traffic, the vehicle may sudden-
ly start to drive off.
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431 Controls in detail
Driving systems
Parktronic system*
The Parktronic system is an electronic
parking aid with ultrasonic sensors that
helps you while parking.
It visually and audibly indicates the relative
distance between the vehicle and an ob-
stacle.
The Parktronic system is automatically ac-
tivated when you switch on the ignition, re-
lease the electronic parking brake or start
the engine and engage gear 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 set the automatic transmission
to P or secure the vehicle in place with the
electronic parking brake and switch off the
engine.
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 bumper (Only visi-
ble without DISTRONIC Plus*)
Warning!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 remains with the driver.
Warning!G
Make sure no persons or animals are in the
area in which you are maneuvering. You
could otherwise injure them.
!Special attention must be paid to objects
with smooth surfaces or low silhouettes (e.g.
trailer couplings, painted posts, elevated cross-
bars 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, espe-
cially at times of snow and ice.
Make sure that the area on the bumpers around
the sensors is free of dirt, ice and/or slush,
otherwise the Parktronic system may not
function properly, see “Cleaning the Parktronic*
system sensors” (
page 559).
iInterference 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.
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