Onn onc50ub18c05 50" led

[yotaman]

I have searched and not an electronics person so forgive me if I am about to sin and fixing to ask dumb questions.
In-Laws set they state it started to start up slower and slower till just black screen but they think still had sound.
I plugged it up and the Red status light is on till you push start and then it goes out and with the back off the only illumination I see is a red glow from the optical port. I checked the voltages on the connector that leads to the control buttons and have 5V where it states it should.
There is only two boards Ima call one the main big board and the other is the small or maybe Tcon board. I have no issue replacing one and see if that is it then the other my only concern is the LEDs' or something in the screen may be the issue ??
Any tips, prayers or advice is appreciated.

Thanks,
Yotaman

[nomoresonys]

Re: Onn onc50ub18c05 50" led

my crystal ball is a little foggy, can you post a good clear straight on picture of the whole back as to see what it is and how everything is connected.

[nomoresonys]

Re: Onn onc50ub18c05 50" led

Have a good read of Budm's most excellent sticky above, here's a link: https://www.badcaps.net/forum/showthread.php?t=25810

[yotaman]

Re: Onn onc50ub18c05 50" led

Thank you for the response. When I get a chance i will get a pic of the back.

Thanks again,

Yotaman

[yotaman]

Re: Onn onc50ub18c05 50" led

See attachments

[nomoresonys]

Re: Onn onc50ub18c05 50" led

heat up the big board with a hairdryer for a couple minutes, what I do is start with the electrolytic caps, heat those up for a couple minutes then try it, see if it stays on longer or if theres any change, dont wait til it cools down try it while its still hot, if no joy try heating the rest of the little blue ceramic caps and the others, if that doesnt do anything try heating the rest of the board, with that symptom I suspect bad capacitor/s. From what I gather they make these onn tvs just as cheaply as possible but theyre prolly still better than samsung.

[lotas]

Re: Onn onc50ub18c05 50" led

Check the voltage on this connector (out backlight) when you turn it on, it rises and if the backlight is not working, the voltage will drop sharply.

[yotaman]

Re: Onn onc50ub18c05 50" led

Thank you both for your responses.
Blow dryer trick did not seem to phase it.
Voltage (DC right) on the red wire pin of that terminal did exactly what you described. Does that say backlight is bad ? if so how hard to change it ? I have only swapped a few TV boards.
Thanks again Guys

[yotaman]

Re: Onn onc50ub18c05 50" led

bump

[yotaman]

Re: Onn onc50ub18c05 50" led

bump bump please

[nomoresonys]

Re: Onn onc50ub18c05 50" led

there: https://www.youtube.com/watch?v=bYJKOFfNGkg