Yet another Samsung bootloop - QE50Q60T

[lotas]

You can place a neat, thin jumper (one wire) so that it does not close anywhere, there is no high voltage and high current. Check the fuses, and measure the resistance of these inductors to ground (LVDS cable must be disconnected).

[lotas]

You need to check with the radiator installed, since the SoC gets very hot here and the thermal protection may trip. Remove the thermal pad and apply a little thermal paste and install the radiator.

[Takeatry]

Put the board back in position? Power on but lvds disconnected? Wire already there got folded underneath when i pulled the board to remove the heat sink

[lotas]

Put the board back in position? Power on but lvds disconnected? Wire already there got folded underneath when i pulled the board to remove the heat sink

There is no need to drop the power and there is no need to install it anywhere when you measure the resistance of the inductors with a multimeter...
Everything is done on the table without connections.

[Takeatry]

Here are the readings. Both fuses blown

[lotas]

Both fuses blown

This is bad, so you don’t have power to the panel, apparently there was a short circuit somewhere on the motherboard or on the panel. All connections and disconnections of cables on the TV are made with the TV de-energized, that is, the plug is disconnected from the socket!

[Davi.p]

Please don't drive crazy, Take a try you just said you have high temperature on the cpu, the fuses you measured are for the main board not the panel, is it needed i continue?

[Takeatry]

I think once I moved the ribbon cable between the panels with the unit on. That was some time ago and I think the tv came shortly after. Maybe I put the meter probe somewhere I shouldn’t have.

[Takeatry]

I have to apologize, I think my mind is going bad fighting with this thing. The fuses are not blown. But the measurements at the inductors are correct. Does this change anything?

[lotas]

But the measurements at the inductors are correct. Does this change anything?

Yes, low resistances are not visible on the inductors, except for one, where 0 Ohm, but this is how it should be; it converts negative voltage (VGL) and this inductor sits on the ground.

[Takeatry]

Ok hopefully the forum will indulge me with a few more questions before I put this thing back in the box and on the shelf. I know I have an option to try a different MB but at this time I won’t go in that direction. That being said have the recent measurements of fuses and inductors indicated the board is ok or are there other testes that can be performed?
There was a situation that I put on my original post that I did not a response to. Maybe a dumb question. As I checked all the capacitors I saw every one had one side with a path to ground check with the audible continuity setting. All except C02 in photo on the right buffer board. Every now and then as was probing I might get a quick single then nothing. It measure 7k ohms across it. The resistor right above it R27 is mega ohm. When the tv still had power and was in the loop I would take voltage measurements. Both sides of the capacitor had 7V as did the closest pin on the resistor. I had an analog meter when I started this. When I tested the opposite pin on r27 it measure what appeared to be 2v then go to -2v. Once when the tv was on and working and I had a digital meter I went to this area again to check voltage. The 7V was on both side of the cap and the pin on r27. When I put the meter on the other pin it jumped to 6+V then proceeded to drop slowly to 0v. I thought I thought I had a possible answer, but at different time through this process I would test components on the left buffer to compare to the right. At one time noticed the same thing on the left buffer board.
Does this seem a normal event in the circuit?
Lastly I re-read a post from approx a year ago. Different Samsung model but same exact conditions as mine, working part of the time, taping method when successful never permanent. There were pictures that showed the same buffer boards as mine. The discussion on the post was similar to all the boot loop posts but there was a mention of cutting some diodes. I have seen this in many other posts but those board were very different. T15 and T16 were discussed in the old post as seen in the other photo below. Lotus recommended testing the clock signal areas on both boards and the pins on the diode to be checked for low on no resistance to ground. I have done this and nothing looked out of the ordinary. There was never a resolution to the old post, so I guess the basic question is if I remove these diodes is there a chance to fix it?
Thanks

[Davi.p]

deleted..

[Takeatry]

Not quite ready to quit on this. I have already started researching my next tv. Which hopefully go on a big sale on what we call Black Friday in the states at the end of November. Since I have nothing to lose I thought I would risk taking some voltage measurements on the smaller components of the buffer panel. After not reading anything other than low 20mV any where on the panel, I was surprised to see 3.3V on the Winbond chip 25q32. I also saw the 3.3v on the diodes T15 and T16. It appeared 3.3 was on every pin on the diodes other than ground. I saw a previous post with similar testing being done and saw removing the lvds was called for. When I did this any pin I touched started at some mV number then slowly dropped to 0. Does tell us anything new?

[Davi.p]

I'm afraid you'll fall in this new market technique of black friday, discounted products that lasts one/two years... my main board is returning to sender due to Post service mess, so i can't help you in decent times, hope i will receive it one day, and also don't lost money for the mess of others, i'm fighting every day with them to solve.. bye..

[Takeatry]

Still not quitting. Did some voltage testing on MB. Found something interesting to me. Picture below shows a chip. Looked for a long time to identify numbers on top but found nothing. I got clear reading of the voltage on all the pins, but when I touched the top right pin the tv shutdown for a short time. I repeated the sequence many times same result. I disconnected the lvds, the voltages did not change and the shutdown also occurred. When the unit shut there was a short booting period. The back lights came on quickly but the standby led blinked 3 times for 5 periods. Does the add any info

[Davi.p]

So at this point i warmely suggest you to do an half reflow to the main processor, so we don't mess around a lot with these poop of tv waiting for a board that will arrive with f****ing Santa claus , this is only a test, not a repair, it worked for me, let'a we see yours.. obviously remove all s**t masking tapes if there are... turn on tv maybe still a little hot to ensure balls contact due to dilatation

[Takeatry]

Was able to borrow a heat gun capable of reaching above 250C and had an adequate thermal couple. Spent a few dollars on proper flux that I could place around the edges of the chip with a syringe. Read the guidelines and YouTube videos on the reflowing process. Protected the board with layers of tin foil. Got the chip up to 250C for 60 seconds. Let it cool and reinstalled it. No help. Same exact reading of voltages. Tv shut still shut when I touched the lead on the x424 chip.

[Diah]

i did the best to warning you at post #26 & #27 but you get hear the wrong bet. no way for you just the way to trash bin.

[Takeatry]

I appreciated and understood your warning. I had nothing to lose but time, which I have plenty of. It was interesting to make the attempts and learn something new. Almost felt like I was in school again.
Thanks to all the forum members that tried to help.

[Diah]

I appreciated and understood your warning. I had nothing to lose but time, which I have plenty of. It was interesting to make the attempts and learn something new. Almost felt like I was in school again.
Thanks to all the forum members that tried to help.

excellent sport spirit