Toyota Yaris Sedan 2008 Quick Reference Manual page 267

4-3. Do-it-yourself maintenance
Checking interval
n
Inspect and replace the air conditioning filter according to the maintenance
schedule. In dusty areas or areas with heavy traffic flow, early replacement
may be required. (For scheduled maintenance information, please refer to
the "Scheduled Maintenance Guide" or "Owner's Manual Supplement".)
If air flow from the vents decreases dramatically
n
The filter may be clogged. Check the filter and replace if necessary.
NOTICE
n When using the air conditioning system
Make sure that a filter is always installed.
Using the air conditioning system without a filter may cause damage to the
system.
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