Toyota 2004 Prius Owner's Manual page 185

If manual on−off of the air conditioning
is desired—
Touch the "A/C" switch to turn the air
conditioning on and touch it again to turn
the air conditioning off.
If the system is used for ventilation, heat-
ing in dry weather or removing frost or
exterior fog on the windshield, turn the air
conditioning off once it is no longer re-
quired. This will improve fuel economy.
The air conditioning can be used for year−
round automatic temperature control in-
cluding cooling and dehumidifying opera-
tion.
(b) Windshield defogging and
defrosting
27p116a
To remove interior fog on the wind-
shield—
Touch the front windshield switch.
To remove frost or exterior fog on the
windshield—
1. Touch the upper side of the tempera-
ture control switch until maximum fig-
ure appears on the temperature dis-
play.
2. Touch the front windshield switch.
3. Push the "HI" of the air flow control
switch to obtain a maximum air flow.
4. Leave the air conditioning on−off button
off.
When the front windshield
touched, the air conditioning is set to op-
erate and the OUTSIDE AIR mode is set.
If you touch the front windshield switch
once again while in the FRONT WIND-
SHIELD mode, the mode then returns to
the last mode used.
The indicator will come on in the instru-
ment cluster while the FRONT WIND-
SHIELD mode is on.
CAUTION
Do not use the front windshield
switch during cooled air operation in
extremely humid weather. The differ-
ence between the temperature of the
outside air and that of the windshield
could cause the outer surface of the
windshield to fog up blocking your
vision.
switch is
185