Samsung UE50JU6400K Blinking Standby light (Won't turn on)

[DIYlife]

Hello

My TV has recently developed a fault, as the title says all that happens when the power is turned on is the Red standby indicator blinks continuously but the TV never actually comes on.

I have already tried to replace the power board and several other components from a working TV (Same model) to see if I could identify the issue. Unfortunately I have been unsuccessful and the issue remains exactly the same.

The TV (Broken one) did have a full set of LED strips replaced about a year ago so not sure if there is a short somewhere. I have disconnected the LED's altogether but that made no difference to the problem, but maybe I'm thinking it needs the voltage draw from the LED's to allow power to the screen?

If anyone can offer some advice on this it will be greatly appreciated?

Regards

 

[RandomGrinch]

I have already tried to replace the power board and several other components from a working TV (Same model) to see if I could identify the issue. Unfortunately I have been unsuccessful and the issue remains exactly the same.

Did you try the power board etc. from the non-working TV, in the working one, to check that they still operated correctly?

but maybe I'm thinking it needs the voltage draw from the LED's to allow power to the screen?

I believe it does need some current draw from the LEDs to turn on; it's common for a single IC to monitor this and if it detects a problem (it may be only slightly out of spec), the TV won't turn on.

I take it you did the usual basic step of unplugging it for several minutes, while holding the power button, to attempt to discharge of the capacitors?

 

[DIYlife]

Yes I swapped the board from the non working TV and it powered up the other TV (so that's ruled out).

Yes I tried the usual basic steps also but nothing cleared the issue. I'm thinking if I can extend the LED connector cable from my working TV's LED board to the faulty TV then that could confirm the LED's? without stripping down the TV first.

 

[RandomGrinch]

Yes I tried the usual basic steps also but nothing cleared the issue. I'm thinking if I can extend the LED connector cable from my working TV's LED board to the faulty TV then that could confirm the LED's? without stripping down the TV first.

Yes, if you can. That would be what I would try next.
They may be able to carefully sit back to back?

 

[RandomGrinch]

it's common for a single IC to monitor this and if it detects a problem (it may be only slightly out of spec), the TV won't turn on.

This is what I meant - this video is related to a Sony TV, but I believe the same concept applies to Samsung.
Probably not something to DIY, if you don't know what you're doing, but interesting nonetheless...

 

[DIYlife]

Thanks - very interesting, I have changed out the main board with a working unit so it definitely points towards the LED’s. I don’t mind replacing them all to get it going again. Or if I do strip it down it may just be one strip that’s causing the issue.

 

[Lucid]

Thanks - very interesting, I have changed out the main board with a working unit so it definitely points towards the LED’s. I don’t mind replacing them all to get it going again. Or if I do strip it down it may just be one strip that’s causing the issue.

If one LED has gone then more will follow. Also, you may find a difference in brightness level just replacing one strip, or possibly a slight colour difference. These are both symptoms of the LEDs ageing. Better to replace the whole lot once you know for sure that the LEDs are the issue.

 

[DIYlife]

Yes I agree - if it comes to stripping it down I may as well replace all the LED strips.

 

[DIYlife]

Tried the working TV with the other LED board but made no difference (No LED’s lit - just getting red slow flashing standby and a blue flashing LED on T Con). While I had it apart I swapped the power board, main board and T Con board between the 2 tv’s

Working tv is ok still but other tv is still exactly the same (same fault).

I’m starting to think it could be the screen itself that’s faulty?