Samsung QE55Q60TAUXXU - flashing backlight and flashing standy light--no image

[learnmore]

Hello Community!

CASE DETAILS

Promblem Signs: Backlight on 1 sec off 7sec > repeat && Red standby light: 1blink, off 3 sec, 2 blinks, off 5 secs, 2 blinks, off 3 sec, restart cycle

13V present on powerboard output. Backlight continues flashing after removing cables to pannel one at a time and even with both disconnected. NOTE: backlight STOPs flashing and remains on when connector between powerboard and mainboard (note Tcon built in) is disconnected.

Tried inserting firmware on USB and left it in for a few hours, but no change

??Potential issue: I note the coil and surrounding (messy as I removed/reinstalled them all) caps in image XXX have a 0.6ohm resistance to ground. I injected volage and the most the board drew was 0.6amps, nothing seemed to get hot. Removed all connecting caps, but the coil had the same resistance to ground. I thought of removing the closest IC but the caps connected to it are all okay and it didn't get hot under the IR camera when I injected 1-3 volts.

UNIT DETAILS

Model: Samsung QE55Q60TAUXXU
Mainboard & Tcon (combo board): DFVC2038 BN41-02756B-000 DATE: 2019.12.17
eMMC: THGBMJG6C1LBAIL
Bios (Flash memory): Winbond 25Q80DVSIG AND Winbond 25Q40CL (next to GPU)

I've got a RT809H programmer with 158 adapters but just now learning about flashing and how to use it.

QUESTIONS:

1. If its a memory corruption issue, which IC do I flash eMMC, Winbond 25Q80DVSIG OR Winbond 25Q40CL (next to GPU) and what do I flash onto the IC?

2. For future reference, how do you tell which memory IC needs flashing or something is wrong with it?

3. I've also been seeing some videos about JTAG and eMMC. Is this generally a method for fixing the eMMC without removing it from the board?

4. Are you ment to hold the power button down on the remote for a specific time (or some other input) after inserting a USB with the firmware?

Research is ongoing, as I'm trying to move from simply replacing to repairing boards if possible

Thanks in advance for sharing your knowledge and experiences!

[learnmore]

FIXED! Mainboard Replacement
Thank you for the journey and support for all of you who commented
A a component level, I wonder if maybe an Emmc change/reprogram would have worked but did not want to risk messing with the working board and I was unable to procure a dump for the model, perhaps next time!

[CapLeaker]

Using the RT809h on EMMC with wires, you can look at my Dreamlink T1 repair. Gives you an idea how I did it with EMMC on and off the board.
https://www.badcaps.net/forum/troubl...d-working-dump

You just can't go round and flash the hell out of everything and see what sticks. You can do that maybe as a one before last resort. If you did find a short to ground, investigate it. Maybe it's a shorted MLCC cap. Read my Kuman repair on how I figured that short out. https://www.badcaps.net/forum/troubl...nerator-repair

I think you got enough to do at the moment, Maybe post some high resolution pictures of your turkey and go from there.

[learnmore]

Thanks Cap! I'm checking your post now. Apologies, I've added the photos. I should have done the first time around. Image ending 12206 has the coil that reads 0.6ohms to ground and all the messy caps around that I removed, but coil still showed 0.6 after the were all off the board. Voltage injection under IR didn't show anything remarkable :/

[learnmore]

One more thing, how do you deduce what to flash?

[lotas]

Image ending 12206 has the coil that reads 0.6ohms to ground and all the messy caps around that I removed, but coil still showed 0.6 after the were all off the board. Voltage injection under IR didn't show anything remarkable :/

That's how it should be, this coil sits on the ground to convert negative voltage relative to ground for T-CON and it's called VOFF = VGL = VGOFF = VEEG = -5V to -9V, if they knew, they wouldn't have to unsolder these in vain capacitors!

[learnmore]

Noted Lotas, thank you on sooo many levels! First not a short I guess and second 0.6ohm may not necessarily mean shorted power rail for injection

[learnmore]

Lotas, any suggestions on next steps and good practice for idenifying which memory IC (as in my case x2 winbonds and 1 eMMC) needs addressing (providing you have a memory IC issue)?

[Diah]

why you went to check coil and now you want to miss with MB chips / spi.... ... yours were not the first one had panel failed.... so focus on the panel first.

[lotas]

Lotas, any suggestions on next steps and good practice for idenifying which memory IC (as in my case x2 winbonds and 1 eMMC) needs addressing (providing you have a memory IC issue)?

Place the jumper first, now you can check each half of the panel, pulling out the left one, then the right LVDS, and you can determine which half is not working.

[Diah]

Place the jumper first, now you can check each half of the panel, pulling out the left one, then the right LVDS, and you can determine which half is not working.

+1
also i do have the diagram at samsungs threats remarked which CLK pins need to mask at the top LVDS.

[learnmore]

Place the jumper first, now you can check each half of the panel, pulling out the left one, then the right LVDS, and you can determine which half is not working.

Ah, I failed to add the jumper before testing without each LVDS. Lotas, so I'm not a total robot what does this jumper do or better yet where can I learn about it?

[learnmore]

+1
also i do have the diagram at samsungs threats remarked which CLK pins need to mask at the top LVDS.

Yes please, Diah. If you mean a diagram with which pins to tape off please share, I've done it before with trial and error and those thin lines can be a pain.

[lotas]

Ah, I failed to add the jumper before testing without each LVDS. Lotas, so I'm not a total robot what does this jumper do or better yet where can I learn about it?

This jumper will simulate that the panel is connected to the motherboard when the lvds cables are disconnected, the TV will no longer reboot.

[learnmore]

This jumper will simulate that the panel is connected to the motherboard when the lvds cables are disconnected, the TV will no longer reboot.

thanks

[Diah]

if you search the forum of samsung TU / NU / MU /RU you will find it..
for example this what i found in my profile but i cant tell to which serie it belong

[learnmore]

if you search the forum of samsung TU / NU / MU /RU you will find it..
for example this what i found in my profile but i cant tell to which serie it belong

Will do and thanks again for your input.

[learnmore]

if you search the forum of samsung TU / NU / MU /RU you will find it..
for example this what i found in my profile but i cant tell to which serie it belong

Hey Diah,

I've been searching the Samsung forums using various keywords but yet to find the post about blocking the clock lines. Whenever you can spare a minute, please help me find it.

[Diah]

....

[lotas]

First you need to determine which side is not working.

[learnmore]

Thank you both, working on it now