Lexus RX400h2006 Owner's Manual page 360

AUDIO
(a) Before using the remote control (for new vehicle
owners)
2. Remove the insulating sheet.
The batteries are already set in the remote control with an
insulating sheet, which prevents the batteries from being
discharged. Before using the remote control, remove the
insulating sheet according to the following procedure.
To remove the insulating sheet:
1. Remove the battery cover.
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