Lexus 2004 GX470 Owner's Manual page 293

AUDIO
After replacing the battery, check that the controller operates
properly. If the controller still does not operate properly, contact
your Lexus dealer.
278
Headphone input jacks
To use the jack, push the lid.
You can enjoy the rear seat audio system with commercial
headphone.
To use the headphones, connect them to the jack.
The key must be in the "ACC" or "ON" position.
Finish