Hi. This monitor has a strange fault. When switched on without signal
the screen illuminates and the "check signal cable" display moves around
the screen as it should. However, when I connect a signal, I get a brief
screen of garbled lines (very brief indeed) then the backlights go out.
The power LED also goes off, though it comes back on again, but with no
display.

I have checked the various capacitors on the PCB with an ESR meter, also
the power supply in the same way. The voltages coming from the power
supply appear correct.

Has anyone experienced this fault? The RGB signals go to a SE7888 i.c.
which appears to drive the screen. I assume at least part of this is
working due to the no signal display being good. Is it possible that
something has failed internally in this i.c.? Could the solution be
simpler than that (my experience has shown these chips seldom fail)

Does anyone have one laying around in a scrap monitor?

Thanks.