Philips 42PFL7403H/10 chassis q529.1e-la blown fuse [1U01] on SSB board

[xerian]

Hello. I have this LCD TV on my bench for over a week and can't realy find a problem.
TV set gives me a 2 short red led blinks. I thought there is a problem with loosen back cover on speakers wich is the typical problem to this signal, but it was ok.
There is a blown fuse on 12V incoming rail of DC DC converter on SSB board. I've replaced it with picofuse to be shure isn't a fuse defect only, but it blows it right away. I've tested 4 mosfets (7U02,7U05,7U06,7U08) and they look ok.
So far I have expirience on power boards and this is so small for me.
Does someone already had a similar problem with this SSB? Where should I look for gleach.
I've atached service manual  DC/DC scheme if someone would take a look.

Thank you
Regards
Dany