I know the differences between 04-06 and 07-08 Navs but my question is there a physcial difference on the screen and wire harness? The reason I ask is that I can get a the screen and dvd drive from an 06 for a great deal and was thinking I can upgrade to the DVD drive from an 07 at a later time. My reservation is that I upgraded my 05 TSX Nav unit with a new one to add backup camera and quicker functionality but the touch points on the newer 06 TSX's were upgraded so the screen was not 100% functional and the voice control stopped working. Does anyone know if this would be the case with the TL?

Good on you for investigating this- there is definitely a difference, and I wouldn't want you to go through what I went through (where I learned the difference after buying a unit that wasn't compatible).

The 2004-2005 navi units have a different wiring harness than the 06 and later models, and you will lose voice control functionality. Not to mention, your navi will not broadcast sound through your car's speakers over music- what will happen if you install a different-harness(ed) unit is that the music volume will decrease (as if you were hearing navi directions) but you will hear no navi voice or sounds, and it will come back after the period of time the directions would've taken.

I'm not sure about the screen functionality (since I had to replace my CD player unit, not the navi screen), but you have to consider that you can't just swap in parts from later-year TLs and expect your car to know how to interface with the part and use its features.

Best of luck to you in your parts search, though!

Thanks, I figured there would be issues. I guess I'm sticking with waiting to find a good deal on an 07 navi.