TCL 65C715 backlight issue

[Cornito]

You mean that the BL ON signal is not sent to the PSU by the motherboard.

BL ON is not so easy to take, but measured it and was present.

I'll take the requested picture tomorrow.
Regards

[Diah]

you are afraid of the glued screen..LOL.... i advised you to arrange space at your place and take out the screen and keep it in safe place,, to have access to BL to be sure of them before order..

[EazyBone]

Several tvs have main board send signal to PSU for backlight. How are you certain this isn't that way. But understood on legend. If you don't believe that's a possibility then it's PSU and LEDs.

[Cornito]

Several tvs have main board send signal to PSU for backlight. How are you certain this isn't that way. But understood on legend. If you don't believe that's a possibility then it's PSU and LEDs.

I've checked that point and i have the signal.
Please find attached the requested pictures

[Cornito]

you are afraid of the glued screen..LOL.... i advised you to arrange space at your place and take out the screen and keep it in safe place,, to have access to BL to be sure of them before order..

Yep i've in mind your advice, just want to avoid having the tv open for weeks, it takes a lot of space dissassembled

[Cornito]

So tried to desassemble it to confirm led strips références, and i broke the panel.
End of the story

[EazyBone]

Sorry to hear, we are a forum to help figure stuff out. Next time can ask for help on how to remove the panels like that I would of shared my knowledge on how to.

Do you plan on still testing to see what was potentially wrong with the lights.

[Cornito]

You've done all possible and i thank you for that.
It's my mistake, i was too quick in a corner and broke the panel.

[nomoresonys]

Many many videos on backlight replacement on youtube, breaking a panel stings for a while BUT on the bright side, it was only a tcl.

[Cornito]

Ahah it's my first panel breakage since my first repair.
Ot must happen at one time.
Bought it with backlight default, my pitty but no so much money loss.
I learnt so much.

[EazyBone]

Yea, I randomly do that also. But are you still gonna test the tvs lights or did you rage quit. I have done this also lol

[Cornito]

Nope I'll not rage quit, I'll disassemble the whole tv to sell parts in order to reduce the price for this lessons.
I'll test led by led to found out the real root cause to confirm hypothesis.

[EazyBone]

Excellent. Those blue LEDs can be taken out and sold sometimes also, if they are working that is. My qn82raxxxx whole set is like $200 and had 48 strips. On eBay 4 strips alone sold for $50 so who knows. Right on

[Diah]

Nope I'll not rage quit.

don't forget to delete TCL from yours daily live dictionary

[Cornito]

don't forget to delete TCL from yours daily live dictionary

Ahah why?

[Cornito]

Excellent. Those blue LEDs can be taken out and sold sometimes also, if they are working that is. My qn82raxxxx whole set is like $200 and had 48 strips. On eBay 4 strips alone sold for $50 so who knows. Right on

I've completely dismantled the TV to take parts that can be sold. It's a huge mess; everything is glued, so it's quite impossible to fix a backlight issue.

I measured all voltages LED by LED. The LED tester shows 6V directly on the majority of the LEDs, but on some, for a few milliseconds, I can see 9.2V, 15V, or 153V before reaching a steady 6V.
It's as if the internal resistance needs to heat up a bit before becoming steady.

This could be the root cause leading to PSU protection mode.

So based on that I don't think I'll sell any LED strip

[peterkos2]

I've completely dismantled the TV to take parts that can be sold. It's a huge mess; everything is glued, so it's quite impossible to fix a backlight issue.

I measured all voltages LED by LED. The LED tester shows 6V directly on the majority of the LEDs, but on some, for a few milliseconds, I can see 9.2V, 15V, or 153V before reaching a steady 6V.
It's as if the internal resistance needs to heat up a bit before becoming steady.

This could be the root cause leading to PSU protection mode.

So based on that I don't think I'll sell any LED strip

Greetings. How did you disassemble the display together with the frame? Thanks

[peterkos2]

Finally it seems i found the LED part number: GIC65LB100_3030F2.1D_V0.7_20200108




Found these on AliExpress :
https://fr.aliexpress.com/item/10050...|query_from%3A

https://fr.aliexpress.com/item/10050...|query_from%3A

On pictures i can now understand why i've got so many connector and same not at the same height on the same led strip.

I hope this can help somebody,

But these links on Aliexpress are for 75" TV

[Cornito]

Greetings. How did you disassemble the display together with the frame? Thanks

I had to place a plastic card between the frame and the LCD Panel.
The plastic card has to be thin as possible, and just sliding the card, you should be able to unglue the LCD-Panel from the frame.

Be sure that the bottom frame is removed first, LCD Panel is covered in the bottom of the screen

[Cornito]

But these links on Aliexpress are for 75" TV

Try to search with the reference i've shared, Link may have changed