Sony XBR-70X850B won't power on and has no standby light. I've replaced the power supply with no change. Need help to positively identify failing component

SOURCE: RE: Flashing "Standby" light

Go here http://www.avsforum.com/avs-vb/showthread.php?t=928945&page=4
for my post #108 for a step-by-step solution with pictures. $21.83 is all it cost me. I fixed my own TV as many others on that forum have. Feel free to contact me at [email protected] if you run into difficulties.
-Dave

SOURCE: sony xbr standby light problem power wont turn on?

the problem either in short horizontal output x-sistor or in power supply unit.

SOURCE: standby light blinks 13 times

Hi,
13 blinks is backlight error.. can be 1 of 2 things, 1st bad inverter board (on left side panel looking from back) it has several plug ins to the panel as it supplies voltage to the backlights.2nd could be panel itself as backlights are built into it they can't be replaced. Inverter is probably around $200 +labor, panel= buy new tv... they are outrageously expensive. Good luck!

SOURCE: Fujitsu Plasma Screen won't power up

This is most likely caused by the Main Power pcb.

See Fujitsu Service Bulletin on this problem in a similar model from Fujitsu. -see link below
http://tomtom2k5.free.fr/fujitsu/PDP-0035-06.pdf

A competent service technician should be able to implement the service bulletin.
A similar service bulletin is probably available for your model. Request bulletin from Fujitsu '[email protected]'

SOURCE: My Sony KDL-26S3000 won't turn on it well get stuck in standby

Please see the troubleshooting chart, BU1 board part # A-1268-869-A, cost approx $230.