Toyota PRIUS Owner's Manual page 316

5. Install the filter and filter case in the
reverse order of removal.
Set the filter in the filter case correctly.
INFORMATION
82p009a
The air filter should be installed prop-
erly in position. The use of air condi-
tioning with the air filter removed
may cause deteriorated dustproof per-
formance and then affect air condi-
tioning performance.
4. Remove the filter from the filter case
and replace it with a new one.
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