Toyota Lexusc Owner's Handbook Manual page 377

AUDIO
Front audio system operation Selecting the mode
All the modes of the front audio system can be operated on the
rear seat entertainment system.
When the same mode is selected on the front and rear audio
systems simultaneously, the system can be operated on the
front audio system.
If the radio mode is selected on the front and rear audio
systems at the same time, AM and FM modes cannot be
changed on the rear seat audio system.
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