Sansui 18" flat screen, built in 2010.

[CoogarXR]

If it's something in the inverter section, and you already subbed caps, about the only things left are bad CCFL tubes, or bad transformer.

The CCFL tubes, the most effective way to test them is with a good inverter (I built a CCFL tester from a dead portable DVD player; I use its inverter board and a 9v battery to light the tubes).

Another way to test CCFLs is to pull them out of the screen, but leave them connected. Power up the TV. Usually you will see if one doesn't light. Swap the cables and see if the same one doesn't light. If the same one doesn't light, it's dead. If the CCFL lights in it's new position, it's the inverter.

Inverter Transformers- If there's more than one transformer on the board measure their primary and secondary resistances and see if they match the readings from the other transformer.

I find dead CCFL tubes in these smaller monitors pretty regularly. Especially the ones that use two pairs (two along the top, and two along the bottom).