Hello fellow techies
Beware folks, turns out pioneer is booby trapping their products these
days. You get the top cover off, you see a "case open switch" which
opens once the top's off. If you now power up the set, with the switch
open, your unit gets "locked". Both standby and power on l.e.d.s glow
together and this state is listed in the service manual as "trap switch
operation" under the LED-lighting patterns/error codes section. A
little googling led me to this post.....

http://www.freelists.org/archives/tv.../msg00000.html
"When servicing Pioneer products such as Plasma and Projection units.
Be
sure the set is unplugged
before removing the back cover. There is a trap switch that will open
and if the unit is powered up. The set will
go into copyright protection mode. Nothing will work again until a
unlocking process is done. Each unit has a different
process to follow to restore operation. Beware!"

The service manual explains it so......
For video data transmission from the Media Receiver to the PDP-434HD
and PDP-504HD-series Plasma Displays, digital
signals are used. Therefore, this unit adopts the HDCP (High-bandwidth
Digital Content Protection) system for copyright
protection. This unit is also provided with a detection switch (TRAP
switch) that will prohibit the unit from being turned on again
"if the upper plate of the unit is accidentally opened," in order to
prevent the panel technology from being leaked out.
The TRAP switch is disabled while the unit is turned off.
When performing internal diagnosis of the PDP, fix the switch to the
OFF position using adhesive tape before turning on the
unit. After servicing, be sure to remove the adhesive tape.

Well you've probably guessed what my next question is......How do i
unlock this receiver?????????
Thanx in advance,
Jango