hello pela pe ... look .... the front led does not turn you on either ... search the google map to see if you find anything ... then look at the source plate ... if you see a bloated condenser something that catches your attention ... the other is already harder ... get a source of 12 v and 5 v ... according to what I tell you the source plate .. and connect the power supply with a separate source you understand there you know if the motherboard works but it makes no sense to repair a source that is broken after the TV .... I explain myself .... the essential thing is to see that Voltages gives you the safe source is 12 and 5 apart from 3.3 ... I got some 12v can be a car motorcycle battery ... then you have to put a couple of things that give you 5v from the battery to battery and 3.3 ... there you can try it ... it grants you already to review the source ... you have to measure the transistor of the source ... notice that it is in google etc ... anything to the orders