If the battery voltage is too low, the rear window
defroster may switch off.Activating/deactivating
XTurn the SmartKey to position2in the ignition
lock (Ypage 121).
XPress the ¤button.
The indicator lamp in the ¤button lights
up or goes out.
Problems with the rear window defroster
ProblemPossible causes/consequences and MSolutions
The rear window
defroster has deactiva-
ted prematurely or can-
not be activated.The battery has not been sufficiently charged.
XSwitch off any consumers that are not required, e.g. reading lamps,
interior lighting or the seat heating.
When the battery is sufficiently charged, the rear window defroster
can be activated again.
Switching air-recirculation mode
on/off
General notes
You can deactivate the flow of fresh air if
unpleasant odors are entering the vehicle from
outside. The air already inside the vehicle will
then be recirculated.
If you switch on air-recirculation mode, the win-
dows can fog up more quickly, in particular at
low temperatures. Only use air-recirculation
mode briefly to prevent the windows from fog-
ging up.
The operation of air-recirculation mode is the
same for all control panels.
Activating/deactivating
XTurn the SmartKey to position 2in the ignition
lock (Ypage 121).
XTo activate: press theebutton.
The indicator lamp in the ebutton lights
up.
Air-recirculation mode switches on automati-
cally:
Rat high outside temperatures
Rat high levels of pollution
When air-recirculation mode is activated auto-
matically, the indicator lamp in the ebutton
is not lit. Outside air is added after about
30 minutes.
XTo deactivate: press theebutton.
The indicator lamp in the ebutton goes
out.
iAir-recirculation mode deactivates auto-
matically:
Rafter approximately five minutes at outside
temperatures below approximately 45 ‡
(7 †)
Rafter approximately five minutes if the
"Cooling with air dehumidification" func-
tion is deactivated
Rafter approximately 30 minutes at outside
temperatures above approximately 45 ‡
(7 †) if the cooling with air dehumidifica-
tion function is activated
Switching the residual heat on or off
General notes
The residual heat function is only available in
vehicles for Canada with dual-zone automatic
climate control.
It is possible to make use of the residual heat of
the engine to continue heating the vehicle for
approximately 30 minutes after the engine has
been switched off. The heating time depends on
the set interior temperature.
iThe blower will run at a low speed regardless
of the airflow setting.
118Operating the climate control systems
Climate control
Important safety notes
GWARNING
If you operate information systems and com-
munication equipmen tintegrate din th evehi-
cle while driving ,you will be distracte dfrom
traffic conditions. You could also lose control
of th evehicle. Ther eis aris kof an accident.
Only operate th eequipmen twhen th etraffic
situation permits. If you are no tsur ethat this
is possible ,park th evehicl epayin gattention
to traffic condition sand operate th eequip-
men twhen th evehicl eis stationary.
You must observ eth elegal requirements for th e
country in whic hyou are currentl ydriving when
operating th eon-board computer.
GWARNIN G
If th einstrumen tcluste rhas faile dor mal-
functioned, you may no trecognize function
restriction sin systems relevan tto safety. The
operating safet yof your vehicl emay be
impaired .Ther eis aris kof an accident.
Drive on carefully. Hav eth evehicl echecke d
at aqualified specialist workshop immedi-
ately.
The on-board computer only shows message sor
warning sfrom certain systems in th emultifunc-
tion display. You should therefor emak esur e
your vehicl eis operating safely at all times .
If th eoperating safet yof your vehicl eis
impaired ,pull ove ras soo nas it is saf eto do so.
Contac t aqualified specialist workshop.
Fo ran overview, see th einstrumen tpanel illus-
tration (
Ypage 32).
Displays and operation
Instrument cluster lighting
The ligh tsensor in th einstrumen tcluste rauto -
matically control sth ebrightness of th emulti-
function display. In daylight, th edisplays in th e
instrumen tcluste rare no tilluminated.
The lighting in th einstrumen tcluster, in th edis-
plays and th econtrol sin th evehicl einterior can
be adjusted usin gth ebrightness control knob. The brightness control knob is locate
don th e
botto mleftof th einstrumen tcluste r
(
Ypage 32).
XTurn th ebrightness control knob clockwise or
counter-clockwise.
If th eligh tswitch is set to th eÃ, Tor
L position ,th ebrightness is dependen t
upon th ebrightness of th eambien tlight.
Speedometer with segments
The speedometer is divided int osegments on
vehicles wit hDistanc ePilot DISTRONIC.
The segments in th espeedometer indicat e
whic hspee drange is available.
RDistanc ePilot DISTRONI Cis activated
(Ypage 150):
On eor two segments in th eset spee drange
ligh tup.
RDistanc ePilot DISTRONI Cdetects avehicl ein
fron tmoving mor eslowly than th estore d
speed:
The segments between th espee dof th evehi-
cle in fron tand th estore dspee dligh tup.
Tachometer
!
Do no tdriv ein th eoverrevving range, as this
could damag eth eengine.
The red ban din th etachometer indicates th e
engine's overrevving range.
The engin eis limite dwithin arange to protect
th eengin ewhen th ered ban dis reached.
Outside temperature display
You should pay special attention to road condi-
tion swhen temperatures are aroun dfreezing
point.
Bea rin min dthat th eoutside temperature dis-
play indicates th etemperature measured and
does no trecord th eroad temperature.
The outside temperature display is in th emulti-
function display (
Ypage 176).
Ther eis ashort delay before achang ein outside
temperature appear sin th emultifunction dis-
play.
174Displays and operation
On-board computer and displays