Toyota PRIUS Owner's Manual page 535

Washer fluid
Open the lid.
1
Check the washer fluid level on
2
the level gauge.
"NORMAL"
1
"LOW"
2
If the washer fluid level is at
3
"LOW", add washer fluid.
PRIUS_OM_OM47A31E_(EE)
6-3. Do-it-yourself maintenance
535
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