Toyota Prius Owner's Manual page 342

3-1. Using the air conditioning system and defogger
Adjusting the settings

Changing the cooling and dehumidification function
Press
The cooling and dehumidification function switches between on and off
each time the button is pressed.

Adjusting the temperature setting
Press "" to increases the temperature and "" to decreases the
temperature on the

Adjusting the fan speed
Press  (increase) or  (decrease) on
The fan speed is shown on the display. (7 levels)
Press
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to turn the fan off.
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