
Permanent SPEEDTRONIC
You can use the on-board computer to limit
the speed permanently to avalue between
160 km/h(e.g. for driving on winter tyres) and
the maximum speed ( Ypage 193).
Shortly before the store dspeed is reached, it
appears in the multifunction display.
Permanent SPEEDTRONIC remains active,
even if variable SPEEDTRONIC is deactivated.
You cannot exceed the stored limit speed,
even if you depress the accelerator pedal
beyond the pressure point (kickdown). DISTRONIC PLUS
Important safety notes DISTRONIC PLUS regulates the speed and
automatically helps you maintain the dis-
tance to the vehicle detected in front. DIS-
TRONIC PLUS brakes automatically so that
the set speed is not exceeded.
On long and steep downhill gradients, espe-
cially if the vehicle is laden, you must select
shift range
1,2or 3in good time. By doing
so, you will make use of the braking effec tof
the engine .This relieves the load on the brake
system and prevents the brakes from over-
heating and wearing too quickly.
If DISTRONIC PLUS detects a slower-moving
vehicle in front, your vehicle is braked in order
to maintain the preset distance to the vehicle
in front. G
WARNING
Do not change down for additional engine
braking on a slippery road surface. This could
cause the drive wheels to lose their grip and
the vehicle could skid. G
WARNING
DISTRONIC PLUS is only an aid designed to
assist driving. The driver remains fully respon-
sible for the vehicle's distance from other
vehicles, the vehicle's speed and for braking
in good time. DISTRONIC PLUS does not react in particular
to:
R
pedestrians
R stationary obstacles on the road, e.g. stop-
ped or parked vehicles
R oncoming and crossing traffic
DISTRONIC PLUS may not detect narrow vehi-
cles driving in front,e .g. motorcycles, or vehi-
cles driving on a different line. Therefore,
always pay attention to traffic conditions even
when DISTRONIC PLUS is activated. Other-
wise, you may fail to recognise dangers in
time, cause an accident and injure yourself
and others. G
WARNING
DISTRONIC PLUS cannot take account of road
and traffic conditions. If DISTRONIC doe snot
recognise or no longer recognises the vehicle
in front, do not activate DISTRONIC or, if it is
already active, deactivate it. This is especially
the case:
R before corners
R on filter lanes
R when changing to a lane with faster moving
traffic
R in complex driving situations or where lanes
are diverted, e.g. at roadworks on a motor-
way
DISTRONIC PLUS otherwise maintains the
current speed set by you or accelerates up to
the set speed.
DISTRONIC PLUS cannot take account of
weather conditions. Deactivate, or do not
activate, DISTRONIC PLUS:
R if the roads are slippery, snow-covered or
icy. The wheels could lose their grip when
braking or accelerating. The vehicle could
start to skid.
R if the sensors are dirty or there is poor vis-
ibility, e.g. due to snow, rain or fog. Dis-
tance control may be impaired.
Always pay attention to traffic conditions
even when DISTRONIC PLUS is activated. 156
Driving systemsDriving and parking 

If DISTRONIC PLUS detects that the vehicle
in front is driving faster, it accelerates your
vehicle, but only up to the speed you have
stored. G
WARNING
If you depress the brake, DISTRONIC PLUS is
deactivated unless yourv ehicle is stationary.
DISTRONIC PLUS then no longer brakes your
vehicle. In such cases, control the distance
from vehicles travelling in fron twith the brake
alone. You could otherwise cause an accident
and thereby injure yourself and others. The
drive rremains fully responsible for the vehi-
cle's distance from other vehicles, the speed
being driven and for braking in good time.
Changing lanes
If you change to the overtaking lane, DIS-
TRONIC PLUS supports you if:
R you are driving faster than 60 km/h.
R DISTRONIC PLUS is maintaining the dis-
tance to a vehicle in front.
R you switch on the respective turn signals.
R DISTRONIC PLUS does not detec tadanger
of collision.
If these conditions are met, your vehicle is
accelerated. Acceleration will be interrupted
if changing lanes takes too long or if the dis-
tance between your vehicle and the vehicle in
fron tbecomes too small.
i When changing lanes, DISTRONIC PLUS
monitors the left lane on left-hand drive
vehicles and the right lane on right-hand
drive vehicles. G
WARNING
DISTRONIC PLUS is only an aid designed to
assist driving.
It is not a substitute for attentive driving. The
driver remains fully responsible for the vehi-
cle's distance from other vehicles, the vehi-
cle's speed and for braking in good time.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to recognise dangers in time, cause an accident
and injure yourself and others.
Vehicles with COMAND Online
i The following function is not operational
in all countries.
DISTRONIC PLUS uses additional information
from your navigation system so that it can
adapt to certain traffic situations. This is the
case if, while following a vehicle, DISTRONIC
PLUS is active and you:
R approach or drive around a roundabout
R approach a T junction
R turn off at a motorway exit
Even if the vehicle in front leaves the detec-
tion range, DISTRONIC PLUS temporarily
maintains the curren tdriving speed and does
not accelerate. This is based on the current
map data in the navigation system. Example
:roundabout
The current speed is maintained:
R approximately 10 seconds before the
roundabout/T junction and approximately
1.5 seconds when driving on a roundabout
R approximately 12 seconds before reaching
a motorway exit and approximately
4s econds after the motorway exit
Afterwards, the vehicle accelerates back to
the set speed you specified.
Stopping G
WARNING
Never get out of the vehicle when DISTRONIC
PLUS is activated. Driving systems
159Driving and parking
Z 

specified direction until the arrow is white
and a warning tone sounds.
X To reverse into the parking space: main-
tain the steering wheel angle and reverse
carefully.
X Stop as soon as you hear a warning tone,
at the latest when PARKTRONIC sounds the
continuous warning tone.
The Parking Guidance finished mes-
sage appears in the multifunction display
and a warning tone sounds. You may be
asked to steer in adifferent direction and
the nchange gear. In this case, further dis-
plays in the multifunction display will direct
you to the final position.
X Manoeuvre if necessary.
X Always observe the warning messages dis-
played by PARKTRONIC (Y page 168).
Cancelling Parking Guidance X
Press the PARKTRONIC button on the
centre console (Y page 169).
Parking Guidance is cancelled immediately
and PARKTRONIC is deactivated.
Parking Guidance is cancelled automatically
if it is no longer possible to guide you into the
parking space, or if a malfunction occurs.
The parking space symbol goes out and a
warning tone sounds. The Parking Guid‐ance cancelled message appears in the
multifunction display. ATTENTION ASSIST
Important safety notes ATTENTION ASSIST helps you during long,
monotonous journeys such as on motorways
and trunk roads. It is active in the 80 km/h
to 180 km/h range.
If ATTENTION ASSIST detects typical indica-
tors of fatigue or increasing lapses in con-
centration on the part of the driver, it sug-
gests taking a break. G
WARNING
ATTENTION ASSIST is only an aid and may
detect your tiredness or lapses in concentra-
tion too late or not at all. It is not asubstitute
for a well rested and attentive driver.
Fatigue may cause you to recognise hazard-
ous situations too late, misjudge a situation
or react slower. For this reason, make sure
you feel rested before you begin driving and
during your journey. Always take breaks in
good time and regularly, especially during
long journeys. Otherwise, you may fail to rec-
ognise dangers in time, cause an acciden tand
injure yoursel fand others.
ATTENTIO NASSIST assesses your level of
fatigue or lapses in concentration by taking
the following criteria into account:
R your personal driving style, e.g. steering
characteristics
R journey-related parameters, e.g. time of
day, length of journey
The functionality of ATTENTION ASSIST is
restricted, and warnings may be delayed or
not occur at all:
R if the road condition is poor, e.g. if the sur-
face is uneven or if there are potholes
R if there is a strong sid ewind
R if you have adopted a sporty driving style
with high cornering speeds or high rates of
acceleration
R if you are predominantly driving slower
than 80 km/h or faster than 180 km/h
R if you are currently using COMAND Online
or making a telephone call with COMAND
Online
R if the time has been set incorrectly
R in active driving situations, such as when
you change lanes or change your speed Driving systems
173Driving and parking Z 

R
the traffi csigns are poorly illuminated.
R there are ambiguous traffic signs, for
instance near roadworks or on multi-lane
roads.
Traffic signs always have priority over the
Speed Limit Assist display. Speed Limit Assist
cannot detect road and traffic conditions. It is
not a substitute for attentive driving.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognise dangers in time, cause an accident
and injure yourself and others.
Information in the multifunction display :
Traffic sign indicating aspeed limit or the
end of a speed limit (example)
; Speed Limit Assist is available and the
warning function is switched on in the on-
board computer
= Units used in the traffic sign displayed
Briefly showing detected traffic signs in
the multifunction display
X Activate the Speed Limit Assist warning
function using the on-board computer
(Y page 189).
Symbol ;appears.
At raffic sign indicating a speed limi torthe
end of a speed limit :appears in the mul-
tifunction display for around five seconds
as soon as it is detected. Any other infor-
mation in the multifunction display is hid-
den for this period. Permanently showing detected traffic
signs in the multifunction display
X
Display Speed Limit Assist using the on-
board computer (Y page 189).
At raffic sign indicating a speed limi torthe
end of a speed limit :appears in the mul-
tifunction display as soon as it is detected.
Traffic sign indicating a speed limit :is
generally displayed until:
R a traffic sign indicating the end of the
speed limit is detected.
R you make a turn.
R you leave or enter a town.
R the road type changes (e.g. motorway,
country road).
R you have travelled a certain minimum
distance without the traffic sign being
repeated or detected again.
i You can also activate Speed Limit Assist
using COMAND Online. The maximum per-
missible speed is shown in the COMAND
display; see the COMAND Online operating
instructions. Driving systems
175Driving and parking Z