Samsung UN55MU6290 Boot loop

[anupkg1985]

Re: Samsung UN55MU6290 Boot loop

Set stays on if right side ribbon is disconnected and starts rebooting if it's connected so that means there is short on right side driver board. However without right ribbon connected also there is no VAA voltage. Is it expected or something else is also wrong? Could that be issue on the main board as well?

[Davi.p]

Re: Samsung UN55MU6290 Boot loop

In certain models if not both half of screen are connected but only one the tension not come out, so you don't know which side has problems, maybe if you block VAA only with tape the rest of tensions come out, try, first one side per time..

[anupkg1985]

Re: Samsung UN55MU6290 Boot loop

I tried with removing big caps on driver board however no luck, same symptoms are there.

[Davi.p]

Re: Samsung UN55MU6290 Boot loop

So you removed all big caps in both boards? maybe is not enough, some times there are some caps for the HAVDD, in yours maybe HVAA that fails, have you checked by magnifier first? In post #11 i can't see well, aren't there any diodes? Marked with Dxx... If there are test them. But without instruments is difficult..

[anupkg1985]

Re: Samsung UN55MU6290 Boot loop

I understand that, getting a hot air station. Also find the pictures of the both side boards, I didn't notice any diode on the board. All I could find are caps and few resistors.

[anupkg1985]

Re: Samsung UN55MU6290 Boot loop

Attaching few more snaps as post limitations of 10 photos.

[Davi.p]

Re: Samsung UN55MU6290 Boot loop

As i have said, there are some caps that holds HVAA, them must measure about 8,5v, if you find some of the caps that doesn't hold any charge but are smaller than the ones on VAA them are supected. It's a long job without instruments.

[Sibiemofokeng]

Re: Samsung UN55MU6290 Boot loop

hey you all guys ,im new here but what supposed to be done there is simpleon that model ,someone can think many things about thiy issue,the cure is one ,make screen test Anupkg by removing the lvds cables,start with the rite one u will see no solution,then go to the left one the problem lies there,i mean if you are at the back of the tv ,the right side of the screen,count about 10,12,14 pins from left ofthat cable ,put a piece of tape there not so big , you will see the changes,continue cutting different size of the tape and put it ther ,remove the not working one,by so doing you disable the ckvs there ,the stvp there,the ckvbs there ,that tv will play and light up the screen.thanks

[anupkg1985]

Re: Samsung UN55MU6290 Boot loop

Hi,thanks for your suggestion however I don't think its an issue with clock signal as tv doesn't turn on. Most probably it should be short on the either side as Davi P suggested. I'm waiting for my equipment, so meanwhile will try your solution as well.

[Davi.p]

Re: Samsung UN55MU6290 Boot loop

Removing of the capacitors can be made with a sharp cutter by gently apply pressure at the base, but it's a bit risky, the cap can fly away in the hyperspace...

[anupkg1985]

Re: Samsung UN55MU6290 Boot loop

Update- Checked fee more caps on faulty side however no luck. I gave up on it and decided to remove cof tab bonding cables and after removing 3 tabs tv fired up and could see 3/4 od the screen. Not sure if the short was in the panel itself. Could someone confirm?

[Davi.p]

Re: Samsung UN55MU6290 Boot loop

You removed the bottom side tabs? No comment!

[anupkg1985]

Re: Samsung UN55MU6290 Boot loop

Yes, did I make a mistake? I know it's not repairable now however as I said, I gave up and just wanted to check whats the issue. Does that mean panel was ok?

[Davi.p]

Re: Samsung UN55MU6290 Boot loop

I don't remeber this discussion, i can read it again if i have time to lost but it is unuseful now, removing source cof it's always bad thing and they weren't surely the source of problems, you could have sell entire tv for giving to a more expert tinkerer. It's a bit sad but anyway it's your choice. Maybe there was other tries to do..

...and, for instance, by removing for last the inner tab you did, if i'm right my diagnosis was right then bad cap on a distribution board..