here is picture of the service menu screen with the dvd changer playing a movie from the direct video input on back of the rx300 factory screen. note the DVDCH in the bottom of the picture. that is abbreviation which means the headunit recognizes the dvd changer. the panel ecu listed is only in rx300 sevice menu. its the black box below the screen on the backside of the headunit. it inputs all the radio, ac info to the screen. you can acsess your service menu on your rx300 with navigation by tapping up and down on left side 3 times.
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