Un50mu6070 Mainboard issue

[Storyteller12]

Hi,
I'm having trouble with this TV.
I have confirmed backlights work and power supply is good. There is no tcon on this model.

Issue is the main board. When plugged into the power board the voltage drops from 13v to 9v. all pins that are supposed to be 13v are 9v. . But I cannot find a replacement board anywhere so I'm trying to repair the bad components.

Also to note I tried unplugging the 2 lvds cables to rule out panel issues and same problem persist.

Just need a little help tracking down the bad components.

Any help would be greatly appreciated.

[Davi.p]

Re: Un50mu6070 Mainboard issue

It is a software fault, try to locate an 8 pin chip with marking 25xYYY where xy varies, then freeze it with butane gas or compressed air can, wait 5 sec. then turn on tv..

[Storyteller12]

Re: Un50mu6070 Mainboard issue

Ok, thanks for the tip. Will try this later. However I should have mentioned that the model # is un50mu6070 version de09. When i look at shopjimmy they sell the eeprom but not for this version. So im guessing this might be a different problem. If not where can I get the eeprom for this version de09?

Appreciate the help and I will report back about the eeprom.

[Storyteller12]

Re: Un50mu6070 Mainboard issue

Ok. I did freeze the eeprom and no dice. Nothing changes. I don’t have standby light and voltage still reads 9v. Tried removing the eeprom and plugging in just to see and still the same 9v.

So I believe its something else drawing the power down from 13v to 9.

[Davi.p]

Re: Un50mu6070 Mainboard issue

I don't think do, if the power board reports one only tension but two states 9-13 from stby to on then it is a software issue or bad processor.

[lotas]

Re: Un50mu6070 Mainboard issue

Storyteller12 you can read dump with spi flash W25Q40CL programmer and put it here.

[Storyteller12]

Re: Un50mu6070 Mainboard issue

Lotus,
Sorry don’t have a programmer to read the eeprom.

[Storyteller12]

Re: Un50mu6070 Mainboard issue

Quick update: I got the tv working.

Davi.p thanks for your help. It was the eeprom. I switched it with 55” mu series mainboard I had from a cracked screen.

[Storyteller12]

Re: Un50mu6070 Mainboard issue

Lotas,
What programmer should I get or do you recommend. I’ll upload the dump for you. I’m new to software related issues. This was my first.

[Davi.p]

Re: Un50mu6070 Mainboard issue

if think to repair many in future i suggest at least a RT809F or a TL866Ii plus, them costs about 30 euro, if you need for only some small eprom CH341A will do the job.

[ducky29]

Re: Un50mu6070 Mainboard issue

Lotas,
What programmer should I get or do you recommend. I'll upload the dump for you. I'm new to software related issues. This was my first.

Ch341 $3
TL866, TL866A, TL866II PLUS ~$40
RT809F ~$50
RT809H ~$130

Listed them from cheapest, everyone of them gets the job done in your case.
Watch some reviews on youtube if you wanna learn more about each programmer and what they do.

[Storyteller12]

Re: Un50mu6070 Mainboard issue

Storyteller12 you can read dump with spi flash W25Q40CL programmer and put it here.

Lotas:
I receive my programmer and have dumped the file. Not sure how to upload it for you to fix.

I can send you a link from my onedrive where its stored if that works.

Thanks again for the help.

[diif]

Re: Un50mu6070 Mainboard issue

Put it in a zip file and then use the paperclip icon after clicking Go Advanced below.

[Storyteller12]

Re: Un50mu6070 Mainboard issue

See attached file.

Thanks for the info

[Davi.p]

Re: Un50mu6070 Mainboard issue

the first block is empty, maybe lotas will fill that

[lotas]

Re: Un50mu6070 Mainboard issue

Try it, but when writing this 25Q40 you need to correctly set on the programmer "STATUS REGISTERS"
0x88, 0x42.

[lotas]

Re: Un50mu6070 Mainboard issue

"STATUS REGISTERS"
0x88, 0x42.

[Storyteller12]

Re: Un50mu6070 Mainboard issue

Thanks for the fast reply Lotas. I’ll let you know tomorrow how it works out

[Storyteller12]

Re: Un50mu6070 Mainboard issue

I programmed the old chip and it still won’t work when I installed it. I made sure the status registers were set to 0x88 and 0x42.

Not sure if I’m doing no something wrong since it’s my first time feeling with eeprom.

I do get a message saying chip may be protected. To hit unprotect and check data sheet. Not sure what that means.

I push Unprotect. It seems to have something to do with the status register.

Any ideas?

Thanks again

[lotas]

Re: Un50mu6070 Mainboard issue

Hi, what is your programmer?
Read the contents (dump) again and upload them here.