Un50mu6070 Mainboard issue

[lotas]

Re: Un50mu6070 Mainboard issue

@Iotas. Can you please check my dump? I think its ok but just want to make sure.

Thanks in advance.

Hello, yes your dump is fine (working).

[ducky29]

Re: Un50mu6070 Mainboard issue

Hello, yes your dump is fine (working).

I have 9v on the connector instead of 12v. Psu is tested ok. On one case the standy led lit red,(new 25q40 with another dump) in other cases there is no standby. Already replace 24c256 just to make sure. Should i give it a try to the emmc? I have a dump for this chassis.

[lotas]

Re: Un50mu6070 Mainboard issue

I have 9v on the connector instead of 12v. Psu is tested ok. On one case the standy led lit red,(new 25q40 with another dump) in other cases there is no standby. Already replace 24c256 just to make sure. Should i give it a try to the emmc? I have a dump for this chassis.

It will not work with someone else's dump 25q40, do you still have your native dump? And bring back your native dump eeprom 24c256 (if you saved it). And what was the original problem?

[ducky29]

Re: Un50mu6070 Mainboard issue

It will not work with someone else's dump 25q40, do you still have your native dump? And bring back your native dump eeprom 24c256 (if you saved it). And what was the original problem?

Original problem was 9v instead of 13v on the connector of mainboard. When disconnecting psu from mainboard the leds lit up. I posted my dump yesterday here https://www.badcaps.net/forum/showpo...&postcount=100

I kept the original untouched and I worked with spare dumps. With another 25Q40, on 2 times, I disconnected the cable between psu and mainboard, removed the 220v and then plugged back the cable between psu and mainboard and then put the 220v back on. 13V was stable, standby lit but it couldnt start up becouse the dump was not native. I tried to replicate it again this procedure with a native dump but I was unsuccesful.

[lotas]

Re: Un50mu6070 Mainboard issue

A strange malfunction, and no one has repaired it before you, maybe someone else's dump was already in it. If you flash eMMC, then you need to flash the whole kit (spi, eeprom, emmc).

[edu98.exe]

Re: Un50mu6070 Mainboard issue

@Iotas. Can you please check my dump? I think its ok but just want to make sure.

Thanks in advance.

Hi this file could repair my samsung TV UN55MU6300GXZS with motherboard code: BN41-02568B. LABEL BN97-12961X.
Thank you very much for sharing it. grateful for life.

[lotas]

Hi this file could repair my samsung TV UN55MU6300GXZS with motherboard code: BN41-02568B. LABEL BN97-12961X.
Thank you very much for sharing it. grateful for life.

If the problem is in the firmware, then you need to restore the native dump, and if you do not save the native dump and write down someone else's, then there is a high probability that you will have to look for a working motherboard.

[petersor]

I have one of these UN50MU6070 TVs that's bricked but mine is the AA14 version with main board BN94-12747R. Power supply is outputting correct voltages and the backlights come on when the main board is disconnected. I'll do some tests by removing the LVDS cable to rule out the panel and driver boards, and will try freezing the eeprom but it's looking like a software issue. I have a CH341A on order and should get it next week. When I do I'll post a copy of the bin file I pull from the IC. Anything else you can recommend that I do while I wait for the programmer? One other question - is it better to remove the IC to program it or just read/write it while installed?

Rich

[petersor]

Finally figured out how to use the CH341A and the NeoProgrammer software (I think). Here's the dump from the 25Q80DV. Can one of you take a look at it to see if it's corrupted and repairable? lotas maybe? I'd appreciate it. This is my first experience with eeprom reading (and hopefully writing). Not as bad as I thought it would be so far.

Rich

[lotas]

Finally figured out how to use the CH341A and the NeoProgrammer software (I think). Here's the dump from the 25Q80DV. Can one of you take a look at it to see if it's corrupted and repairable? lotas maybe? I'd appreciate it. This is my first experience with eeprom reading (and hopefully writing). Not as bad as I thought it would be so far.

Rich

25Q80DV is a dump from T-con, and you need to read the dump from IC1604 (25Q40CL).

[petersor]

Oops. OK. I'll reinstall that one and pull IC1604 . . .

[petersor]

OK lotas . . . Try this one.

[lotas]

OK lotas . . . Try this one.

Your dump is correct, working, the problem is something else.

[petersor]

Interesting. Thanks for checking. Voltages all appear to be OK so I'll have to dig deeper.

Rich

[petersor]

I haven't found anything showing what the voltages should be, but I found one of the coils connected to IC400_UC (VPM1R DC-DC converter IC?) shows a short to ground, so I suspect the IC is shorted . . . It doesn't look like that ic is readily available, so I guess I'll scrap this one.

[lotas]

This inductor already sits on the ground to convert the negative voltage relative to ground (VGL) to power the panel.

What behavior does your TV have, what happens, does it reboot, how does the standby indicator behave?

[petersor]

With the main board power cable disconnected, the backlights come on. With that cable connected to the main board, the red standby LED gives a single, long flash (1 - 2 seconds) every 15 ~ 18 seconds or so. The main board has a steady 12.86VDC and the CPU heatsink gets warm to the touch.

[lotas]

Using a multimeter, check the resistance of the signal lines on the usb and hdmi ports relative to ground; there should not be low or short resistance. Then install a jumper between these points and disconnect the LVDS cables (left, right) one by one and watch the behavior of the TV (disconnect and connect the cables when the TV is de-energized)

[petersor]

The data lines for the USB ports are OK, but both of the HDMI ports show a short on the pins marked with yellow arrows:




For clarification on the jumpers - do you mean to connect the points I've marked in yellow on these two photos?

[lotas]

Regarding Hdmi, the middle pin is gnd, you need signal lines, those that go to the processor (you can see them on the board, 8 lines for each hdmi). Regarding the jumper, connect these two points to each other, as I showed (the arrows are the same conductor).