It seems mostly there were problems with inverter and/or caps. But my model has japanese caps all over the PSU and inverter. It seems to be working when I disconnect +5 V supply to TCon, I got +5 V on main board and even got backlight in such case.
When supply is conneted to TCon, I do not get anything, the problem propagates all the way to PSU which probably goes to safe mode. I did not find anything bad, no fuse is bad, all diodes and transistors on TCon are good.
BTW I got electrocuted two times, the primary heatsinks is alive. I don't know how that is possible, the switching transistor is in TO-220F and the heatsinks is grounded!
ADD// found some small caps having suspiciously high ESR, one 1 uF/50 V has ESR of 85+ ohm, capacity 0,85 uF, not even ancient tiny Daewoo cap has so incredibly high ESR. Also when powering the TCon with just +5 V from old AT PSU, it did not get shorted so maybe there is some problem on some DC-DC module on the main board because of wore-out caps?
ADD2// changed the 1uF cap, now PSU works even with TCon supplied but still black screen. However, there is more small caps which seem screwed in similar way.
When supply is conneted to TCon, I do not get anything, the problem propagates all the way to PSU which probably goes to safe mode. I did not find anything bad, no fuse is bad, all diodes and transistors on TCon are good.
BTW I got electrocuted two times, the primary heatsinks is alive. I don't know how that is possible, the switching transistor is in TO-220F and the heatsinks is grounded!
ADD// found some small caps having suspiciously high ESR, one 1 uF/50 V has ESR of 85+ ohm, capacity 0,85 uF, not even ancient tiny Daewoo cap has so incredibly high ESR. Also when powering the TCon with just +5 V from old AT PSU, it did not get shorted so maybe there is some problem on some DC-DC module on the main board because of wore-out caps?
ADD2// changed the 1uF cap, now PSU works even with TCon supplied but still black screen. However, there is more small caps which seem screwed in similar way.
Half of the computer problems is caused by bad contacts 