Toyota 2009 Avalon Owner's Manual page 292

To prevent battery discharge
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If the interior lights, personal lights and engine switch light (if equipped)
remain on when the door is not fully closed or the interior light switch in
"DOOR" position, the lights will go off automatically after 20 minutes.
Customization that can be configured at Toyota dealer
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Setting (e.g. The time elapsed before lights turn off) can be changed.
(Customizable features
→ P. 448)
3-4. Using the interior lights
3
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