Toyota Corolla 2004 Operating Manual page 138

4. Pull the filter out of the filter outlet.
Inspect the filter on the surface.
If it is dirty, it should be replaced.
132
'04 Corolla_U (L/O 0306)
When inserting the filter in the filter
outlet, keep the arrow pointing up.
INFORMATION
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.
2004 COROLLA from Oct. '03 Prod. (OM12859U)