sharp lc-65ub30u plays but screen is flashing on and off

[Diah]

The backlights remain flashing for 20 seconds after powering the TV off.

however do what i asked you last post.18. unless you need to take out the screen and inspect visually BL and sockets connection under the screen.

[JunkmanJimbo]

however do what i asked you last post.18. unless you need to take out the screen and inspect visually BL and sockets connection under the screen.

I remved the power supply and I removed the LED driver board but I didn't see any cracked solder joints.

[Diah]

I remved the power supply and I removed the LED driver board but I didn't see any cracked solder joints.

the last things disconnect the 4 ribbon cable between T-CON and Panel then turn on see the BL remain flashing... if yes keep them disconnected and take it apart.... tv will remain work with out screen unless you have stable BL

[Davi.p]

anyway, Jimbo i never repaired a similar defect on a similar set {Local dimming type), my guess is that those two many pins QFP ic on the blue board are something like a specialized CLPD, with D/A and so on, with their own program inside, the program went bad (voltage transients etc) and they are no more able to drive the mosfets, you see the light again when shut down because of that long column of electrolitic caps still charged, i suggest you to try and find a replacement blue board..

Note from admin. Removed negativity from this post. All opinions and users are welcome and should be respected. Personal attacks will result in a ban.

[Diah]

also you need to figure out the BL_ON signal which it go to PSU or LED driver boards if it remain on stable or it cut off and on.... to be sure every things are correct then take it apart

[JunkmanJimbo]

anyway, Jimbo i never repaired a similar defect on a similar set {Local dimming type), my guess is that those two many pins QFP ic on the blue board are something like a specialized CLPD, with D/A and so on, with their own program inside, the program went bad (voltage transients etc) and they are no more able to drive the mosfets, you see the light again when shut down because of that long column of electrolitic caps still charged, i suggest you to try and find a replacement blue board..

Note from admin. Removed negativity from this post. All opinions and users are welcome and should be respected. Personal attacks will result in a ban.

I looked for a LED driver board but apparently the only way to get it is to buy the power supply.

[Diah]

Note from admin. Removed negativity from this post. All opinions and users are welcome and should be respected. Personal attacks will result in a ban.

Aggressive personality will not fixed by deleting content only,
now is the right time to stop my accounts on this site.

OP sorry that i cant continue with you... really sorry. good luck for all.

[JunkmanJimbo]

also you need to figure out the BL_ON signal which it go to PSU or LED driver boards if it remain on stable or it cut off and on.... to be sure every things are correct then take it apart

I am getting steady voltage at the BL_ON terminal. Do you still think it's a backlight problem?

[JunkmanJimbo]

Aggressive personality will not fixed by deleting content only,
now is the right time to stop my accounts on this site.

OP sorry that i cant continue with you... really sorry. good luck for all.

Come on Diah. You got me this far.

[Davi.p]

People can read, we are not analphabed, Diah started the battle..

anyway, Jimbo, try ti find the datasheet of the 2 LED board controlllers..

[JunkmanJimbo]

People can read, we are not analphabed, Diah started the battle..

anyway, Jimbo, try ti find the datasheet of the 2 LED board controlllers..

Where would I find that?

[Davi.p]

normal web search or from manufacturer's site directly.. today is difficult..

[JunkmanJimbo]

normal web search or from manufacturer's site directly.. today is difficult..

I can't find the datasheet. I'm going to order another power supply to see if that fixes the problem. If that doesn't fix it I will assume there is a backlight problem. Thanks for your help. I will let you know if that fixes it.

[Davi.p]

Note for moderators: i ask again that *** filters my messages like i did with him, otherwise we are here always battleing and him that tells he leaves the forum and he really does not.. bhe

see note below - admin

[Admin]

Note for moderators: i ask again that *** filters my messages like i did with him, otherwise we are here always battleing and him that tells he leaves the forum and he really does not.. bhe

Davi.p - it's up to you to go to your settings and select hide for members you don't want to see. The forum is welcoming to all opinions (including the member you mentioned) and all users are welcome to contribute to any thread. All we ask is that things are kept positive.

[Davi.p]

Is it normal that the questioned person tells "don't listen to him, unresponsible man etc etc.."? How can a correct forum permit this? I feel not inferior to him tchnically.. one can sentence "that is error" or "that is error for me" , not prevaricate, i made the error myself in the past, reading totally wrong diagnosis i felt useful for the requester to let him to know that, not ruining a chance to fix a device.. only this.. everybody knows me personally thinks i'm good educated guy, only in the forums i am 'taken as a bully, punk etc..

[nomoresonys]

Any update?

[JunkmanJimbo]

Any update?

I ordered and installed a power supply but that wasn't the problem. I dissassembled the tv to check the backlights. While checking the backlight strips with a LED backlight tester I found one backlight that wouldn't come on at first. After turning the tv on, all the backlights, including the one that wouldn't come on with the tester, came on and started flashing. These are 6 volt backlights. I checked the voltage at that one backlight and the voltage would climb to 12 volts +. So, I changed that one backlight with a new one and that fixed the problem. Thank you guys for all your help.

[nomoresonys]

Glad to hear it, Diah was working hard there, thanks for the "prompt" feedback. AND guess who was right again, good work Diah.

[nomoresonys]

Davi.p - it's up to you to go to your settings and select hide for members you don't want to see. The forum is welcoming to all opinions (including the member you mentioned) and all users are welcome to contribute to any thread. All we ask is that things are kept positive.

Not too hard to see who is the bad apple here, is it? Indeed even a pig who lost his sense of smell could find that truffle. That member seems to be trying to get all of us out, my vote is JUST he goes. He has been the rotten apple for a VERY long time.