LG 32LF585B (Flashes two or three times)

[orientalsniper]

Hello all, not used to be repairing TV's, received an LG 32LF585B, it has standby light, if I try to turn it on, it flashed two or three times and then goes off and I have to unplug it in order to recover standby light.


Power Board is: EAX65391401 (3.0)
Main Board is: EAX65610206 (1.0)


Fed 3.5V (from PSU) to PWR_ON and DRV_ON


I can measure 12V and 24V and also the LED backlights get ON.


Does this mean the damage is on the mainboard? What could be the most probable cause?

[budm]

Re: LG 32LF585B (Flashes two or three times)

Hello all, not used to be repairing TV's, received an LG 32LF585B, it has standby light, if I try to turn it on, it flashed two or three times and then goes off and I have to unplug it in order to recover standby light.


Power Board is: EAX65391401 (3.0)
Main Board is: EAX65610206 (1.0)


Fed 3.5V (from PSU) to PWR_ON and DRV_ON


I can measure 12V and 24V and also the LED backlights get ON.


Does this mean the damage is on the mainboard? What could be the most probable cause?

You are on the right track since you are able to force on the power supplies and the backlights.
The problem is on the main board somewhere, since you do not have PWR_ON and no DRV_ON so more likely something relate to MCU.
Can we see pictures of the main board? May be you can do good visual inspection and try to locate some Voltage regulators on the board and test the Voltages.

[orientalsniper]

Re: LG 32LF585B (Flashes two or three times)

Thank you budm, I was hoping for your input.


I will check the mainboard tomorrow and post photos of the readings, just wanted to be sure it's a mainboard issue sign, I have about two days to repair it, so if I'm unable to, I will just order the mainboard.

[orientalsniper]

Re: LG 32LF585B (Flashes two or three times)

Hello, I got the new board, but the connection is different, can I desolder the connection from the old board into the new board? Or will that not work?

[budm]

Re: LG 32LF585B (Flashes two or three times)

Those two PCB assemblies are not the same.
The same blank PCB can be stuffed to make many difference PCB assemblies for the needed TV models.
As you can see, the LVDS connectors is not at the same, tuner assembly are not the same so each board is made to match with the LCD panel and for what ever model of the TV is made for.
Do not try this new board with your TV since we do not know the pinouts of the LVDS connector, you can damage the main board or the T-CON.
You need to match the PCB assembly as printed on the barcdoe stickers. when you try to buy the new PCB assembly.
FW of the two boards also may bot be the same.

[orientalsniper]

Re: LG 32LF585B (Flashes two or three times)

Sending back the board is not an option now, tuner is not needed, do FW's have to match to work if LVDS pinouts match?


If not, my last option is to do a comparison diagnostics to find out what's wrong with bad board, diode reading would be the way to go?

[budm]

Re: LG 32LF585B (Flashes two or three times)

1) What you can try at this point is to put the board in but do not connect the LVDS cable,
then see if you will get the PWR_ON and DRV_ON all not.

2) You will have to figure out of you have to move or install some parts fro the switched 12V feeding the LVDS connector power pin.

3) I have no idea how you can verify the FW version of the old and the new board.

4) When you force on the PWR_ON and DRV_ON with the old board in place. Were you able to see the image on the screen, get sounds, and all other functions?

5) What are P/N as printed on the barcode stickers of both boards?

[orientalsniper]

Re: LG 32LF585B (Flashes two or three times)

1) Without LVDS connected, backlight and speakers are on as soon I plug cord.

4) When I fed those pins I'm 70% sure there was no image (checked with flashlight) nor sound.

5) They are both EAX65610206 (1.0) in PCB, however in stickers they are: EBL61400103 (old) and EBL61380101 (replacement)

[budm]

Re: LG 32LF585B (Flashes two or three times)

I do not know what you can do to make this board to function the same as the original board.