So I was curious.

I am not tech savvy enough to know the differences, but I know there is a "dvd player" mounted in my trunk.

Is it possible to make that play dvds on my nav screen?

 

In short, no.

There is a device you can buy that goes in-line with the screen's wire harness though. It lets you hook up your own video source like an XBox, DVD player, etc.

Read this thread for more details:
Navi to Video Conversion

 

x2

do a search and you'll find plenty of info.

:ibtl:

 

The DVD player in the trunk is used to access the maps on the DVD disc. DVD discs hold more data than CD discs, which is why DVD's are used.

In order to play DVD's, you will have to buy and install a DVD player. There was a "hack" (at least for the 06+...I don't know about the pre-06 version)....whereby you can plug the DVD player into the back of the navi's DVD player and then send a signal to the navi and trick it that you're going in reverse...this will cause the navi's DVD unit to play the stream from your aftermarket DVD player. This trick was intended for a rear-view camera, which isn't given to the TSX (to make the TL/RL more worth the higher cost ;-P)