When plugged in to power outlet and switched on, this tv power-cycles for random time even for 1h and after switches on and works for some time, after starts to power cycle again. In "good period" it can be unpowered and powered again, still works.
Power supply checked and caps are kinda ok (visual inspection and some of them was unsoldered to check capacity).
Motherboard BN94-11233M / BN41-02528A
Found that, putting some freezing gas on element marked "81244/608486" screen dims couple of times and then goes power cycling again. Probably it is some kind of DC-DC converter with at least 2 channels (positive and negative), but I can't find what actually it is. Measuring just package (without pins), it measures 6x6mm. Also put couple of voltage measurements when it works.