a simple way to help get a quick idea is by turning the set on and:
Short Pins 1 and 2 of P1 (Pin 1
is noted by a triangle) on Ctrl
PCB while the set is playing and
the pattern will display for as
long as you keep the short in
place This pattern is generated on the control PCB independent of
the main chassis. If after utilizing this pattern the picture still exhibits no video it may be one of the PDP support boards (Control, Ysus, Zsus, X and Y Drive
PCB’s). If the pattern displays OK then look for a chassis side problem.
it can be a guessing game sometimes.
good luck