Samsung Q6F edge LED section not working

[nubinator]

Trying to fix Samsung Q6F with dark vertical area and when I unplug motherboard and turn on tv 1 backlight section is not coming on but with LED tester all the sections work. On TV power supply I measure on +side 130v for all sections and on -side I get 55v for all sections except the one not working which is only 5v.
How do I tell if problem is PSU or strip? On the LED tester it reads 68v for all sections. I fully expect it to be a bad strip cause the strips and diffuser are so melted and cracked im surprised any LEDS work

[nubinator]

Re: Samsung Q6F edge LED section not working

I guess its power supply board fault because i swapped the connector to the other strip and same line not working on that one either.

[Storyteller12]

Re: Samsung Q6F edge LED section not working

It’s the backlights. Unplug both backlight connectors from the psu and remove the main board connector from psu. Plug in and measure voltage on backlights connectors. Should be the same output for both connectors. If so it’s backlights.

[Storyteller12]

Re: Samsung Q6F edge LED section not working

Just to note though. Unless you have another plastic diffuser it’s not worth fixing. It will always have a line of light where that crack is and look like crap

[KYBOSH]

Re: Samsung Q6F edge LED section not working

Just to note though. Unless you have another plastic diffuser it's not worth fixing. It will always have a line of light where that crack is and look like crap

+1

You 'MAY' be able to rotate the diffuser 180° degrees so the cracks are at the top and a fresh clean surface is mated against the LEDs but many of the diffusers I have see wont allow this. Either there are tabs on the diffuser to ensure it cant be install backwards/upside down or the etching stops 0.5" from the end instead of going all the way to the end. The lack of etching (not the right word but you get the idea) will prevent proper diffusion and distrubution of the light emitted by the LEDs.

I read once where someone was able to take the diffuser from a larger TV and cut it to size for their TV. Thats likely not possible for you as TVs of this model larger than 65" are incredibly rare and Im not sure how good the edge of the diffuser would look after being cut as a DIY. The diffuser is plastic and melts/browns pretty easily. If you used a saw you would have to then come back and sand down and polish the edges to make it optically clear. Not impossible but man... that's a lot of work to get it optically clear enough not to get a halo effect near each LED.

[nubinator]

Re: Samsung Q6F edge LED section not working

It’s the backlights. Unplug both backlight connectors from the psu and remove the main board connector from psu. Plug in and measure voltage on backlights connectors. Should be the same output for both connectors. If so it’s backlights.

Theres only 1 connector for backlights. 12 pins, 6 lines, 2 LED strips. Line 1 has low voltage on minus pin no matter which LED strip I connect it to so has to be problem with PSU. LED tester also shows no issue with either strip. On PSU all voltages otherwise normal +130v on all +pins and 65v on all -pins except Line 1 only showing 5v.
Anyone know what I can try to diagnose problem?

And yes I have a new diffuser for it, I had his tv for a while waiting for another 65 samsung QLED to come along

I attach picture of power board if anyone can help. Seems its the same power board as NU8000 model too.

[Storyteller12]

Re: Samsung Q6F edge LED section not working

Unplug everything from the psu and plug in. What reading do you get on the 6 diodes labeled led on the psu

[nubinator]

Re: Samsung Q6F edge LED section not working

they're all 138v

[nubinator]

Re: Samsung Q6F edge LED section not working

Ah was just a loose connection at the PSU connector

[Storyteller12]

Re: Samsung Q6F edge LED section not working

Nice!!!! Glad it was something simple and free of cost. I would still replace led strips since you have it opened. There not expensive and obviously the original ones were driven hard that’s why it melted the plastic

[EazyBone]

Re: Samsung Q6F edge LED section not working

+1

You 'MAY' be able to rotate the diffuser 180° degrees so the cracks are at the top and a fresh clean surface is mated against the LEDs but many of the diffusers I have see wont allow this. Either there are tabs on the diffuser to ensure it cant be install backwards/upside down or the etching stops 0.5" from the end instead of going all the way to the end. The lack of etching (not the right word but you get the idea) will prevent proper diffusion and distrubution of the light emitted by the LEDs.

I read once where someone was able to take the diffuser from a larger TV and cut it to size for their TV. Thats likely not possible for you as TVs of this model larger than 65" are incredibly rare and Im not sure how good the edge of the diffuser would look after being cut as a DIY. The diffuser is plastic and melts/browns pretty easily. If you used a saw you would have to then come back and sand down and polish the edges to make it optically clear. Not impossible but man... that's a lot of work to get it optically clear enough not to get a halo effect near each LED.

If you turn it, it will cause the bottom to be very bright. They are meant to be one way, believe me I tried it lol.

Find a crack screen 65 on marketplace or something and then replace diffuser, and those LEDs for sure.

[nubinator]

Re: Samsung Q6F edge LED section not working

Oh no new problem the diffuser out of KS8000 is 3mm longer top to bottom and wont fit above led strip. Any ideas how to cut 3mm off the top of the diffuser ?

[nomoresonys]

Re: Samsung Q6F edge LED section not working

Maybe something like this, the line can be taped to try to keep the edges smoother when cutting, as in put long piece of tape on, make line on middle of tape and cut, might not need the tape: https://www.amazon.com/Scissors-VANJ...A19R46UBHFRE7V

[nubinator]

Re: Samsung Q6F edge LED section not working

Scissors would be nice but it would crack. I'm thinking Dremel which prob melt it as well and then sand it back

[nomoresonys]

Re: Samsung Q6F edge LED section not working

Not sure what scissors would do, suppose one could do it with a good sharp utility knife/box cutter, technique would be score it a few times til thru, could practice on a salvaged piece if available.

[nomoresonys]

Re: Samsung Q6F edge LED section not working

Like this, only it won't be near as hard since plexiglass is much tougher than the sheet: https://www.youtube.com/watch?v=CRFEVggauTQ

[nomoresonys]

Re: Samsung Q6F edge LED section not working

That would be easiest, who wants to deal with melting, which is what you get with a power tool in this situation.

[nubinator]

Re: Samsung Q6F edge LED section not working

Well used Dremel and it worked but yeah just melts so it's messy and slow. razor and straight would be way better.
With diffuser on I can see I need LEDs strips asa few LEDs are dim.

Does anyone know if qled just means it has that orange filter sheet and blue leds or is the diffuser different too? I thought I had to get qled to replace this diffuser but it just seems like normal white led one

[EazyBone]

Re: Samsung Q6F edge LED section not working

Pretty sure Qled got the blue led and yellow diffuser (according to anothers words) but I dont know for sure. There is a edge lit qled huh? Learning a new.

Yes lol I probably would of used straight edge and razor and slow cut/snap it off. Of course cutting top

[nubinator]

Re: Samsung Q6F edge LED section not working

Still got a fair bit of blue seeping through the bottom. That QLED filter was burnt too at the bottom but I didn't replace that so I guss thats why.