Yeah, in most states, as far as I know, it's illegal. So, I'm not going
to help you with that. And on top of that it's dangerous. Having another
person in the car, lighting a cigarette, talking on the phone, etc. is
hard enough, but watching a DVD is totally different. It usually needs
your full attention. That is why you would need the emergency brake on,
so idiots don't have wrecks while driving while watching a movie.
/end rant

Yeah, it's an RTO4873 IC in the Pioneer unit itself, though it may be
labelled as something else in your particular unit.  You have to flip it
upside down, remove the screws, bang it gently with a rubber mallet at all 4
corners, and it should pop right off.  You'll see a black IC near the center
of the top PCB.  You need to disable it.  I've found that the easiest way to
do this is to take some solder and short all the pins to each other.  By the
way, use silver solder, and leave the soldering iron on the pins for a long
time so that you can make sure that the solder seeps into the pins really
well to provide the ideal connection between pins.  Good luck.

Now that you've been warned (and yes, it can be dangerous) I thought I'd
let you know that the newer Pioneer units (and I've heard from an
installer that Alpine and Panasonic will be following suit) use an
inertial movement detector instead of just the parking brake, which
basically means just bypassing the parking brake won't fix your problem
if this is a brand-new unit.

Brandonb

In most states (if not all), no video viewing equipment may be
installed/used in such a way that the operator can view programming
while the vehicle is in motion.

Yes, it is extremely dangerous. If you found a way to do it, I'd
never ride with you. You seem to have suicidal tendencies, and I'm not
ready to check out just yet.

If you are bored with driving, let someone else drive and go ahead and
watch a movie.

Spike
1965 Ford Mustang fastback 2+2 A Code 289 C4 Trac-Lok
Vintage Burgundy w/Black Standard Interior; Vintage 40
16" rims w/BF Goodrich Comp T/A gForce Radial
225/50ZR16 KDWS skins; surround sound audio-video.

"When the time comes to lay down my life for my country,
I do not cower from this responsibility. I welcome it."
                                -JFK Inaugural Address

I agree with you guys that it is dangerous, but honestly Im a very safe
driver with not one mark on my record.  Its more for passengers in the car to
watch a movie on a trip, or me to catch a glimpse while in a traffic jam o at
a stop light, not for watch when Im going 70 mph.  It would just be nice to
to be able to flip it on without always putting on the parking break.  I just
bought the newer pioneer model which is supposed to be tougher to bypass.
someone mentioned about taking it apart and doing some minor surgery on it...
lol.. but Im just afraid I might f.ck that up.  a guy at Best buy mentioned
to me that there is a part that you can buy online which you can install to
trick your system into thinking that it is always in park.  Has anyone heard
about this?  Thanks for the insight guys, I appreciate it.