Toyota Yaris Owner's Manual page 98

Make sure you turn the defogger off when
the window is clear. Leaving the defogger
on for a long time could cause the battery
to discharge, especially during stop−and−
go driving. The defogger is not designed
for drying rain water or for melting snow.
NOTICE
z To prevent the battery from being
discharged, turn the
when the engine is not running.
z When cleaning the inside of the
rear window, be careful not to
scratch or damage the heater wires
or connectors.
switch off
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