LED Samsung UE40J6272 flashing red led 6x

[jano101]

Problem Description:

6 year old Samsung UE40J6272 without a single problem
one evening it turned itself off and only the red LED flashes interval 6 times

sometimes the picture pops up sometimes not


logically I thought it was a faulty source

I will take a look at anything burned out, look at the capacitors - they were normally uninflated

I fly capacitors I measure capacitance and ESR everything is OK

the voltage according to the diagram should be 13 but I measure 12.6V

and after a while about how it turns on it drops to 8.7 V and around 12.6-> 8.7V


the power supply is there
L48S1_FSM

if I unplug the board cable, the lighting runs OK

the red LED flashes at 6x intervals


will you help as next ???? how to diagnostic?

[neilc6]

Re: LED Samsung UE40J6272 flashing red led 6x

Samsung TVs do not have blink codes and the front LED flashes when the TV is booting and goes out when the TV is in an ON state. You should be able to turn the TV off. If the TV is on and there is no backlight, you likely have bad backlights. Test for Samsungs is to unplug the cable between the main and power supply board and plug the TV in. This will force the backlights on. If you have no backlights, they are likely bad though bad backlights can damage the power supply. If you get picture once in a while, you likely have a lot shorted and one intermittent going open. I suspect your backlight level is set to max 20/20 which will burn out the backlights.

I would remove the panel and observe the backlights with them forced on. I would be guessing the majority will be burnt out.

[jano101]

Re: LED Samsung UE40J6272 flashing red led 6x

I guess you didn't understand me

the display backlight is OK

also the display is ok

I did a test disconnecting the motherboard from the backlight source is OK

the problem is that the power supply has 12.6 V during the flashing of the red LED then it drops to 8.6 V and this is repeated cyclically

sometimes it happens that the TV starts up normally for about 2 minutes and then the problem recurs around

[neilc6]

Re: LED Samsung UE40J6272 flashing red led 6x

If you look at the silkscreen of the power supply board, the supply voltage is 8V in standby and boosts to 13V with a PS-ON signal from the main board. Monitor the PS-ON signal and if it is dropping when the TV shuts off, your suspect is the main board. 12.6 vs 13.0 isnt an issue.

Second test is to only have one side of the panel connected at a time between the tcon and panel. If the TV stays on with one side good, you have a panel fault.

[jano101]

Re: LED Samsung UE40J6272 flashing red led 6x

do I really understand that I should disconnect the t-con from the main signal board / main boar /?

and if it doesn't turn off then there's a bug in the panels?

[jano101]

Re: LED Samsung UE40J6272 flashing red led 6x

measured voltage on

mainboard connectors

[dick_barton]

Re: LED Samsung UE40J6272 flashing red led 6x

The backlight signal from the mainboard to turn on the backlights is missing according to your photo in post #6

The slightly lower voltage on the 12V line can be ignorned.