Toyota 2013 Prius Owner's Manual page 325

Type B
Fog lights can be used when
■
The headlights are on in low beam.
NOTICE
To prevent 12-volt battery discharge
■
Do not leave the lights on longer than necessary when the hybrid system is
off.
PRIUS PHV_OM_OM47787U_(U)
2-3. Operating the lights and windshield wipers
Turns the fog lights
off
Turns the fog lights
on
2
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