I found this website by searching on the specific wiring for in dash DVD. I found some that really didn't know a whole lot about it. The parking brake wire is usually green. There are multiple ways to bypass it to watch a DVD while driveing. One is to ground the DVD player (you can use the ground of the harness) or use a relay. It takes up more room but not needed if you can ground it. Some newer models have made it so a relay is needed not all though. I've had luck an only needed a 4 prong relay once. That's all is needed is a 4 prong relay. Some use a ground and toggle that grounds the player when switched to the position. It works as well but more work than needed.
