Samsung UE40D8000 bootloop ( powerloop )

[nroberto13]

Hi Guys,

After the software update to 1029, my tv worked fine for 1 day and then started to fun. In the beginning the TV was bootlooping after I plugged the outlet to power, TV switched on, showed smasung smart tv logo, and after 1-2 seconds rebooted itself, and this happened over and over again. For a while the tv started after 6-7 reboots worked fine for about 2 hours and then started again to bootloop. Now it is just bootlooping no matter what I do. I tried to replace the power board, but still the same, so I assumed the main is defect. Bought another main, which was taken from a 55d7000 having the same model code as mine, BN41-1622C, but with this main the TV doesn't show anything, I can hear the start relay click, the power led blinks 5 times, and after around 15 seconds reboots. Is there a way to push a D8000 firmware to the new main ( the one taken from 55d7000) without the screen working? I read about the console, tried to connect to the stereo jack, but can't see anything in the terminal, most likely because the RS232 option in the service menu is not set to debug. without the screen working, Is there a way to set RSR232 to debug mode?

Any advise is more than welcome!

Thank you!

[Lordbyte]

Dude, go call Samsung repair service

[nroberto13]

I'm afraid that would cost more than worth the TV . a mainboard at samsung is around 300 euro plus replacement 50 ...

[Lordbyte]

Well, as long as it reboots every 15 seconds, you have no way to upload new firmware.
Try disconnecting mainboard from everything except power-supply ... power-relay still click every 15 seconds ?
You MAY try clearing the EEPROM with a paperclip or a small wire, but .. I dont really believe it will help.
I fear you have a lost cause here ... So sorry.

[nroberto13]

tried disconnecting everything but power and infra receiver from main, but still the same, clicks every 15 secs. tried to disconnect panel too from power supply and still the same? how can I clear the EEPROM? which IC is it and what pins to short? thanks.

[fluffi444]

Check here (if not already found - It sounds like you already know what an EPROM reset is)
http://wiki.samygo.tv/index.php5/UnBric ... 7xx.2F68xx
Your TV is not in the list but maybe one of the listed have the same or similar Mainboard.

BUT: Do this ONLY if you have all your settings from Service menu saved (noted or picture) After EPROM Reset you have to set needed values manually...
As an alternative you can try to find one with the same TV who can give you the settings... Mabey they are already here somewere in Forum

[nroberto13]

I was thinking about moving the flash from my main 40d8000 to the other main from 55d7000, would it make sense? if the board is the same, the difference is most likely in software. As I'm not able to reflash the 55d7000, I could transfer the firmware by moving the flash from the 40d8000? does it make sense? or I'm missing something. I'm not sure which IC would be the flash, any ideas? thanks.

[Gabryc]

Hello, from yesterday I have the same problem on UE46D8000 after activating the automatic channel search.
How did you solved the problem.

[nroberto13]

unfortunately nohow so far . replaced power and main board but in the meantime the backlight burned out too, so still bootlooping. Seems that this is the common behavior for any errors, just bootloop .

[Gabryc]

Hi, in this topic
viewtopic.php?f=65&t=7422
a user has the same problem on Samsung UE40F6670 and solved
with a reset eeprom.
I found in the Wiki tutorial series D
http://wiki.samygo.tv/index.php5/UnBric ... PROM_Reset
You've tried this?