Toyota 2005 Prius Owner's Manual page 111

The system will automatically shut off af-
ter the defogger has operated about 15
minutes.
CAUTION
Since the mirror surface can get hot,
do not touch them when the switch
is on.
Make sure you turn the defogger off when
the window is clear. Leaving the defogger
on for a long time could cause the auxilia-
ry battery to discharge. The defogger is
not designed for drying rain water or for
melting snow.
If the outside rear view mirrors are heavi-
ly coated with ice, use a spray de−icer
before operating the switch.
NOTICE
When cleaning the inside of the rear
window, be careful not to scratch or
damage the heater wires or connec-
tors.
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