Toyota Prius 2011 Manual page 447

STEP 3
CAUTION
When refilling the washer fluid
■
Do not refill the washer fluid when the hybrid system is hot or operating, as
the washer fluid contains alcohol and may catch fire if spilled on the hybrid
system etc.
NOTICE
Do not use any fluid other than washer fluid
■
Do not use soapy water or engine antifreeze instead of washer fluid.
Doing so may cause streaking on the vehicle's painted surfaces.
Diluting washer fluid
■
Dilute washer fluid with water as necessary. 
Refer to the freezing temperatures listed on the washer fluid tank.
4-3. Do-it-yourself maintenance
If the washer fluid level is at
"LOW", add washer fluid.
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