Hi. Strange problem. I have a Viewsonic P810 set that was sitting around
waiting on a component (video amplifier IC) for about a year. I replaced
the component along with some caps, all on the neck board. When I went to
power the set up for checking, the SMPS wouldn't do anything (one tweet
when power applied, one tweet when power removed). If I remove the flat
ribbon cable that connects the neck board to the deflection area, the
monitor powers up nice and detects a video signal, but no picture is
displayed. I can only imagine that something went wrong in my repair, but
I don't know what - it was just an IC and five electrolytic caps.

Is anyone familiar enough with this set or the related Panasonic sets to
know what signals are on this ribbon cable and where I should be looking
for the problem? I have a copy of the service manual, and it doesn't seem
to contain any schematic of the neck board. I'm really at a loss to
explain what I did wrong if anything - I went over all my joints again and
checked connections just in case. The best I can come up with is that I
nicked or torched something unrelated during surgery. That damn neck
board is just packed with tiny SMD stuff.

Thanks.