
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.:
R
a stopped vehicle in a traffic jam
R a disabled vehicle
R an oncoming vehicle
The driver must always be alert, observe all
traffic and intercede as required by means of
steering or braking the vehicle. G
Warning!
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 406).
i If 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 216). 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.
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Nearly all dust particles, pollutants and odors
are filtered out before outside air enters the
passenger compartment through the air
distribution system.
G
Warning!
Severe conditions (e.g. strong air pollution)
may require replacement of the filter before
its scheduled
replacement interval. A clogged
filter will reduce the air volume to the interior
and the windows could fog up, impairing
visibility and endangering you and others.
Have a clogged filter replaced as soon as
possible at an authorized Mercedes-Benz
Center. G
Warning!
Follow the recommended settings for heating
and cooling
given on the following pages and
in the “COMAND automatic climate control”
section. Otherwise the windows could fog up,
impairing visibility and endangering you and
others.
X Keep the air intake grille in front of the
windshield free of snow and debris.
Do not obstruct air flow by placing objects on
the air flow-through exhaust slots below the
rear window.
i If the vehicle interior is hot, ventilate the
interior before driving off, see “Summer
opening feature”
(Y page 283). The climate
control will then adjust the interior
temperature to the set value much faster.
The following climate control functions can
be operated via COMAND:
R Temperature ( Y page 194)
R Air distribution (Y page 195)
R Air volume ( Y page 195)
R Switching off cooling (Æ) (Y page 196)
R Central climate control (Mono)
(Y page 196)
R Footwell temperature ( Y page 197)
R Air flow from air vents (Y page 197) Deactivating the climate control
system
G
Warning!
When the climate control system is
deactivated, the outside air supply and
circulation are also deactivated. Only choose
this setting for a short time. Otherwise the
windows could
fog up, impairing visibility and
endangering you and others.
X Deactivating: Press
rocker switch ^ up
or down.
The indicator lamp in the rocker switch
comes on. You will see Climate Control
OFF in the COMAND display.
X Reactivating: Press
rocker switch ^ up
or down.
The indicator lamp in the rocker switch
goes out. You will see the previous settings
in the COMAND display. Air conditioning
The air conditioning is operational while the
engine is
running and cools the interior air to
the temperature set by the operator. In
addition, the air conditioning dehumidifies
the interior air and helps prevent window
fogging. G
Warning!
If you deactivate the air conditioning, the
vehicle will not be cooled when weather
conditions are
warm. The windows can fog up
more quickly. Window fogging may impair
visibility and endanger you and others.
i Condensated water may drip out from
underneath the vehicle. This is normal and
not an indication of a malfunction.
The air conditioning uses the refrigerant
R134a. This refrigerant is free of CFCs which
are harmful to the ozone layer. 340
Climate control system
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The cooling function can be activated or
deactivated via COMAND (
Y page 196).Automatic mode
When operating the climate control system in
automatic mode, the interior air temperature,
air volume and air distribution are adjusted
automatically.
In automatic mode, cooling with
dehumidification is switched on. This function
can be switched off if necessary. G
Warning!
If you deactivate the air conditioning, the
vehicle will not be cooled when weather
conditions are warm. The windows can fog up
more quickly. Window fogging may impair
visibility and endanger you and others.
X Set the desired temperature
(Y page 341).
X Activating: Press rocker switch à up or
down.
The indicator lamp in the rocker switch
comes on.
X Deactivating: Press rocker switch K up
or down.
or
X Adjust air distribution via COMAND
(Y page 195).
The indicator lamp in rocker switch Ã
goes out. Setting temperature
You can adjust the air temperature for each
of the 3 zones separately. You should raise or
lower the temperature setting in small
increments, preferably starting at 72‡
(22†). X
Increasing/decreasing: Press rocker
switches w up or down or use COMAND
(Y page 194).
The climate control system will
correspondingly adjust the interior air
temperature. Adjusting air vents
G
Warning!
When operating the climate control, the air
that enters the passenger compartment
through the air vents can be very hot or very
cold (depending on the set temperature). This
may cause burns or frostbite to unprotected
skin in the immediate area of the air vents.
Always keep sufficient distance between
unprotected parts of the body and the air
vents. If necessary, use the air distribution
adjustment to direct the air to air vents in the
vehicle interior that are not in the immediate
area of unprotected skin.
For best possible performance of the climate
control:
X Keep the air intake grille in front of the
windshield free of snow, leaves, sticks, and
any other debris.
X Always keep all air vents and grilles in the
passenger compartment free from
obstruction. Climate control system
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Text messages
Safety systems Display messages
Possible causes/consequences and
X SolutionsPRE-SAFE Inoperativ
e See
Oper.
Manual
The PRE-SAFE
®
system has failed. All other occupant safety
systems, such as the air bags, are still available.
X Contact an authorized Mercedes-Benz Center as soon as
possible. PRE-SAFE Function
Currently
Limited
See Oper.
Manual
The PRE-SAFE
®
Brake is temporarily unavailable.
The PRE-SAFE ®
Brake is deactivated because:
R the DISTRONIC PLUS cover in the radiator grille is dirty
R the area
around the sensors in the front or the rear bumper
is dirty
R its function is impaired as a result of heavy precipitation
R the radar sensor system is temporarily inoperative due to
electromagnetic interference near television and radio
transmitter stations, toll stations, speed measuring
systems, etc.
R the system is out of the operating temperature range
R the battery voltage is insufficient
The PRE-SAFE ®
Brake becomes operational again and the
message in the multifunction display disappears when:
R dirt on the radiator grille has fallen off while driving (e.g.
slush or snow)
R the system recognizes full sensor availability (due to
lessening rain or the road surface drying)
R the system is within the operating temperature range
If the message in the multifunction display does not
disappear:
X Clean the DISTRONIC PLUS cover in the radiator grille
(Y page 406).
X Clean the front and the rear bumper ( Y page 406).
X Restart the vehicle.
X Wait until the battery recovers. PRE-SAFE Function
Limited
See Oper.
Manual
The PRE-SAFE
®
Brake is unavailable due to a malfunction.
The BAS PLUS may also be unavailable.
X Contact an authorized Mercedes-Benz Center as soon as
possible. 416
Vehicle status messages in the multifunction display
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Display messages
Possible causes/consequences and
X SolutionsDISTRONIC
PLUS Currently
Unavailabl
e See
Oper.
Manual The DISTRONIC PLUS is temporarily unavailable.
The DISTRONIC PLUS is deactivated because:
R
the DISTRONIC PLUS cover in the radiator grille is dirty
R its function is impaired as a result of heavy precipitation
R the radar sensor system is temporarily inoperative due to
electromagnetic interference near television and radio
transmitter stations, toll stations, speed measuring
systems, etc.
R the radar sensors do not sense any other vehicles or
objects, i.e. road sign or similar to this, for a long time
R the system is out of the operating temperature range
R the battery voltage is insufficient
X If necessary, clean the DISTRONIC PLUS cover in the
radiator grille (Y
page 406).
X Restart the vehicle.
X Try activating the DISTRONIC PLUS again later.
X Wait until the system is within the operating temperature
range or the battery recovers.
The DISTRONIC PLUS becomes operational again without the
engine being restarted when:
R dirt on the radiator grille has fallen off while driving (e.g.
slush or snow)
R the system recognizes full sensor availability (due to
lessening rain or the road surface drying)
R the message in the multifunction display disappears DISTRONIC
PLUS Inoperativ
e The DISTRONIC PLUS is malfunctioning.
The BAS PLUS and the PRE-SAFE
®
Brake are also not
available.
X Contact an authorized Mercedes-Benz Center as soon as
possible. DISTRONIC
PLUS Override You have accelerated. The DISTRONIC PLUS has switched off.
X
Stop accelerating. Vehicle status messages in the multifunction display
421
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