sony kdl-46r473A went crazy after a while

[dellxps15]

hi all
today i got this tv that except back hdmi port that dont work, is working fine for some time, then while watching tv channel through digital cable, tv stop, go black and a big noise start. if i open it the mediatek chip is really really hot

at first i think about bga need reballing , but this one is tsop with normal pins.

what can i do to start throubleshoting it ?

picture of mainboard and psu will follow later. need to open it.

[Agent24]

Re: sony kdl-46r473A went crazy after a while

Bad regulator giving dirty power = overheating CPU and lockup?

[dellxps15]

Re: sony kdl-46r473A went crazy after a while

Bad regulator giving dirty power = overheating CPU and lockup?

umh maybe, or maybe also some bad capacitor, but dunno what measure i have to do

[Diah]

Re: sony kdl-46r473A went crazy after a while

for any TV of Sony when it had unusual Issue,need first to log in service menu diagnose mode to read any error, then reset to shipping condition

[dellxps15]

Re: sony kdl-46r473A went crazy after a while

service mode say nothing. 0 error

one test i have made to the non working hdmi ( the one in the middle of the board) pin hot plug detection is shorted. if i track it it goes to the mediatek mt5367ZUHU chip.

so maybe a bad mediatek chip on this tv ? that chip when tv is turned on become really really hot.

[dellxps15]

Re: sony kdl-46r473A went crazy after a while

i got a 2nd hand mainboard 50€ship included and now tv is fully working. im planning on buy that mediatek chip aswell and change it on the faulty board so i can fix it and sell after that

[dellxps15]

Re: sony kdl-46r473A went crazy after a while

update: after 2 month around november 2018 i got the chip and replaced on the non working motherboard, and tv come back to life even with old board. now after 2 years, bad weather hit that tv again i looked on the pwoblem and tv was booting and showing as normal, but chip start heating up again... so i replaced the chip, but now it sometimes power on as normal and sometimes its like dead.... bad chip or bad board?