Samsung UE40K1502AKXXH - flashing LED, no life but still responsive

[Sebastijan V.]

So, I got this UE40K1502AK(XXH) TV from a friend.
TV has no picture or sound, but it reacts on remote control and power button on bottom side.

- When plugged into mains, the LED is red on. If I use remote to power it on for the first time, it flashes 6x then LED remains off. I assume this would be the same as by normal tv?
- LED also flashes fast when I push any button on remote controller. If I turn it off with remote, the LED will lit solid red. And by next turn-on with remote, it flashes 5x. Also will flash fast when any remote button is pressed.
- The background illumination LED strips are dead, so I can not confirm about the picture - at least I didn't see anything with flashlight.
- I disconnected backlight and used 2 resistors 47ohm/20W in series, to stimulate backlight. Power supply gives 66 V and 710 mA (100% PWM) when Mainboard is disconnected, and 25% PWM when Mainboard is connected.
- All voltages I measured seems reasonable and present (8/13V for Mainboard when standby/full_on, its 5 V ; 3,3 V ; 1,8 V are present at LDOs.) Also voltages on LCD-panel are there (30V ; 12 V ; 3,3 V ; 1,8 V ; 1,2V...). The only fuse there is OK.
- Capacitors on Power-supply were measured and OK. The main capacitor on DC-Link and for backlight primary supply hold their charge for 10 minutes after disconnection from mains.
- CPU is reasonably warm, but not very hot.
- I have desoldered IC801 and IC805 memories and have it here.

Can anyone see anything from the memory content, or is there other fault to be known?

Thank you!

[lotas]

Samsung UE40K1502AKXXH - is the model written correctly? Even Google doesn't know what model it is....

[Sebastijan V.]

Well, it is extended model designation, from UE40K1502AK, as written in the back.

[Diah]

UE40K5102AK not as you wrote UE40K1502AK

[lotas]

Well, it is extended model designation, from UE40K1502AK, as written in the back.

Well, where does it say on the tag that this is UE40K1502AK?

[nomoresonys]

Typo maybe? https://www-samsung-com.translate.go...n&_x_tr_pto=sc

[Sebastijan V.]

Sorry, my bad. Fingers faster than my brains. 😵 (working 3 things at the time is bad idea).

and the memory content, if previous posting failed:


@ If moderators can edit topic name, I would be grateful too.

[Sebastijan V.]

Anyone got an idea for this UE40k5102akxxh? From the uploaded memory chips?
Only potentional thing I found is here:


https://**************/dump/lcd_pdp_.../241-1-0-41921

(some problems with publishing the link?)

But I am not member there...

[lotas]

Anyone got an idea for this UE40k5102akxxh? From the uploaded memory chips?
Only potentional thing I found is here:


https://**************/dump/lcd_pdp_.../241-1-0-41921

(some problems with publishing the link?)

But I am not member there...

Try!

[lotas]

Doesn't work?

[Sebastijan V.]

Thank you for the files.
It appears to be working now - also I connected laptop on HDMI port and there is the picture visible But red LED still flashes 5x when turn on. Maybe this is even the normal behaviour (?!)
Anyway, the backlight is dead and I just ordered new LED backlight unit (glued on aluminium heatsink/highly polished reflector). I will see when I change it - then maybe even flash it back to original.

[Sebastijan V.]

Alright, let me conclude this saga
I received new backlight units (LED strip on aluminium reflector), assembled everything together and it worked! There was "new" SW on chips that Lotas sent me, and there were no issues. Even the language stayed the same (Slovenian). Only detail I saw is that under menu was stated "please find the serial number on a back cover". Which was somehow logical - there was no data about serial number and model in this SW - apparently erased/blank, comparing to original one.
So I flashed both chips back to their original SW. All is working again, the serial number is visible in customer menu. Only the language changed itself to "similiar" (Slovakian), maybe because they are close together on menu. I set it back to our of course.

All well now I feel kind of a embarrassed, because all this could be avoided if I looked into screen more deeply with flashlight... 🙄😶