lg 43LF5400 - UB

[kodiac]

Has anyone had experience with a lg 43LF5400-UB that will not power up?
No standby led, no sound, blank screen - just seems dead.

The pwr supply does have
. 169v on the filter cap
. 200v to the backlights
. all backlight leds ( 72 leds => 2 x 36 ) are good
. 3.2v standby
. 13v to the main board

The pictures included are from ShopJimmy.com


Also what would be the symptoms for a corrupted Eeprom?


Thank You

[nomoresonys]

Re: lg 43LF5400 - UB

With power cord unplugged, unhook cable from powerboard to mainboard, plug power cord in, see if backlights come on and stay on.

[budm]

Re: lg 43LF5400 - UB

Please provide the Voltage readings of all the pins of connector P201, please make sure to put down pin name and follow by the reading of each pin so we can easily see what are missing when TV is plugged in but power switch is not activated and when power switch is activated.

[kodiac]

Re: lg 43LF5400 - UB

nomoresonys

No the backlights didn't come on.

[kodiac]

Re: lg 43LF5400 - UB

budm

P201 Voltages

I don't know if the TV is On or Off because I use the toggle switch and there are no standby or power leds.

Q205 Voltages

[budm]

Re: lg 43LF5400 - UB

https://www.badcaps.net/forum/attach...6&d=1559238999
Can you put down pin name for each pin as requested?

[kodiac]

Re: lg 43LF5400 - UB

P201

[kodiac]

Re: lg 43LF5400 - UB

I'm looking for more P201 pin information.

[budm]

Re: lg 43LF5400 - UB

So do the PWR-ON and DRV-ON change state when power switch is toggled on and off?
Right now the main board is not sending the DRV-ON signal to turn on the backlights circuit.
https://www.badcaps.net/forum/attach...8&d=1559238999
That MOSFET is not being turn on either.
Main board problem at this point, exact cause I do not know. Does it make any different if you heat or cool the main board?

[nomoresonys]

Re: lg 43LF5400 - UB

Mainboard there, 29 dollars, think I would get the one with all three boards for 38, might not need all 3 but nice to have a spare just in case, as always match up sticker numbers or email or call them to try to insure a match. https://www.shopjimmy.com/lg-ebt6348...jr-busylor.htm

[kodiac]

Re: lg 43LF5400 - UB

Thank You

[kodiac]

Re: lg 43LF5400 - UB

I would appreciate knowing the role of the following IC's in this TV;

IC 100 - EEPROM AT24C512C (512KB)
IC 101 - SERIAL FLASH W25Q64FVSSIG (64MB)

The EEprom has to be programmed individually to each TV model?
What is on the EEprom?

Does the Flash have to be programmed individually to each TV model?
What is on the Flash?

If one or both of these IC's have corrupted firmware will this cause a brick TV?


Thank You

[kodiac]

Re: lg 43LF5400 - UB

EEPROM function confusion
https://www.badcaps.net/forum/showthread.php?t=66897

[diif]

Re: lg 43LF5400 - UB

I would appreciate knowing the role of the following IC's in this TV;

IC 100 - EEPROM AT24C512C (512KB)
IC 101 - SERIAL FLASH W25Q64FVSSIG (64MB)

The EEprom has to be programmed individually to each TV model?
What is on the EEprom?

Does the Flash have to be programmed individually to each TV model?
What is on the Flash?

If one or both of these IC's have corrupted firmware will this cause a brick TV?

Thank You

Not 100% sure, but I guess a bit like a computer. The small one has the boot up files and the large one the software of the TV including the image files.

Some TVs share common software others do not. Some Tvs have SPI flash and NAND. Yes, if they become corrupt or fail then the TV will fail to start either fully or partly.

There is a thread at the top of the TV page for EEPROM dumps.

[akis24]

Re: lg 43LF5400 - UB

169v on the filter cap ? 169v on the filter cap? I imagine it is a reading error if it were not so I do not understand how the power supply can work

[budm]

Re: lg 43LF5400 - UB

169v on the filter cap ? 169v on the filter cap? I imagine it is a reading error if it were not so I do not understand how the power supply can work

The DC Voltage on the main filter will be about 120VAC * 1.414 = 169VDC.

[akis24]

Re: lg 43LF5400 - UB

perfect now we are there but I evaluated the network voltage present in Italy 230 vac * 1.414 = 325 sorry ..

[Duranitron]

Re: lg 43LF5400 - UB

Has anyone had experience with a lg 43LF5400-UB that will not power up?
No standby led, no sound, blank screen - just seems dead.

The pwr supply does have
. 169v on the filter cap
. 200v to the backlights
. all backlight leds ( 72 leds => 2 x 36 ) are good
. 3.2v standby
. 13v to the main board

The pictures included are from ShopJimmy.com


Also what would be the symptoms for a corrupted Eeprom?


Thank You

-does the back light lit? the presence of 200volts will lite up the backlight.
-the power supply board is ok because secondary voltage are present.
-try to turn on the unit using the side panel switch.
-try to re attache the panel cord
the problem is in the main board try to focus there.. try to reflash the eeprom. and be patient you can fix it.. happy hunting..

[kodiac]

Re: lg 43LF5400 - UB

does the back light lit? the presence of 200volts will lite up the backlight.
-the power supply board is ok because secondary voltage are present.
-try to turn on the unit using the side panel switch.
-try to re attache the panel cord
the problem is in the main board try to focus there.. try to reflash the eeprom. and be patient you can fix it.. happy hunting..


the back light does not light
there are no side panel switches, there is a single toggle switch on the bottom
the toggle switch will not turn the TV on
and there is no stand by led lit

I replaced the Eeprom, flash, and crystal, from a donor board
I re - programmed the Eeprom and flash using the original firmware - with no luck

I would love to have a LG 43LF5400 firmware .bin dump for the Eeprom and flash

Also I would like to know if I can manually program a LG 43LF5400 software update into the flash?

The current flash .bin seems to be missing a few bytes/bits.
I tried to upload the .bins but I get an invalid file error.



Thank You

[diif]

Re: lg 43LF5400 - UB

The donor board you got the eeprom and flash from, an identical board ?