Mercedes-Benz C-Sedan 2015 Owners Manual - Manual (Page 151)

Problems with the rear window defroster
Problem Possible causes/consequences and M M Solutions
The rear window
defroster has deactiva-
ted prematurely or can-
not be activated.
The battery has not been sufficiently charged.
X
Switch 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.
Activating/deactivating air-recircula-
tion mode
General notes
You can also temporarily deactivate the flow
of fresh air manually if unpleasant odors are
entering the vehicle from outside. The air
already inside the vehicle will then be recir-
culated.
If you switch on air-recirculation mode, the
windows can fog up more quickly, in particu-
lar at low temperatures. Only use air-recircu-
lation mode briefly to prevent the windows
from fogging up.
Activating/deactivating
X Turn the SmartKey to position 2 in the igni-
tion lock (
Y
page 157).
X
To activate: press the g rocker switch
up or down.
The indicator lamp above the g rocker
switch lights up.
Air-recirculation mode switches on automat-
ically:
R
at high outside temperatures
R
at high levels of pollution (3-zone automatic
climate control only)
R in a tunnel (vehicles with a navigation sys-
tem only)
The indicator lamp above the g rocker
switch is not lit when automatic air-recircula-
tion mode is activated. Outside air is added
after about 30 minutes.
X
To deactivate: press the g rocker
switch up or down.
The indicator lamp above the g rocker
switch goes out.
Air-recirculation mode deactivates automati-
cally:
R after approximately five minutes at outside
temperatures below approximately 41 ‡
(5 †)
R after approximately five minutes if cooling
with air dehumidification is deactivated
R
after approximately 30 minutes at outside
temperatures above approximately 41 ‡
(5 †) if the "Cooling with air dehumidifica-
tion" function is activated
Activating/deactivating the residual
heat function
General notes
The residual heat function is only available
with 3-zone automatic climate control on
vehicles for Canada.
Once the engine is switched off, it is possible
to make use of the residual heat of the engine
to continue heating or ventilating the front
compartment of the vehicle for approximately
30 minutes. The heating or ventilation time
depends on the interior temperature that has
been set.
Operating the climate control systems
149
Climate
control