What is RCA cable in front TV Box?

2bzy2c wrote:
Red and white are for speakers Yellow for video.

Almost... Red and White are for left and right audio (line level) signals not speakers.

In the old days, they often used the red/white RCA cables to transfer sound from a home theater system, VHS player or even a game system. You should be able to discard them if you're installing a new TV.

On Newmar your vintage the RCA was FROM the TV to the dash Radio. You put the Dash radio on AUX and the TV volume came thru the Dash radio speakers. On some models, depending on the year, those 2 Audio cables went to the DVD surround system instead in the Overhead above the passenger seat. Doug

Red and white are for speakers Yellow for video.