The Ipod is handled as a CD changer by the headunit.
So if you connect your Ipod to the cable harness of the car, you should press the disc button.
Maybe you have to press the disc button twice.
Then you should see one of your playlists in the display.
Products for the Ipod Interface may be from Vaistech, Dice or GROM Audio which are the most used companys.
You could look at their website for the documentation.
Also it is possible that Lexus has sold the Panasonic brand Ipod Interface, which is
a good service from Lexus because they have the information to build it in from their service system AIM.
brgds from
sdohn