lg tv 42lv450 does not start

[Moddingscreen]

Good morning everyone is a new user of the forum, I have a small problem with the power supply of a lg EAX62865401 tv, the tv flashes the standby LED and subsequently also the white led and then turn off totally, I checked the voltage 3.5v and it is present but the relay does not attack, what can I do?

Thank you all for your valuable advice, and excuse my English

[Moddingscreen]

Re: lg tv 42lv450 does not start

could it be the motherboard?

[dskall]

Re: lg tv 42lv450 does not start

Need voltages from connector that goes from power supply board to main board. Will need pin#- PIN DESCRIPTION -Pin voltage in standby-Pin voltage when pushing power button and picture of connector on power supply board.
Format:
Pin# - Pin Description - Pin Voltage standby - Pin voltage power on
1 - XXXXXXX - XXv - XXXv
2 - XXXXXXX - XXXv - XXXv
3 - XXXXXXX - XXXv - XXXv
4 - etc.

[Moddingscreen]

Re: lg tv 42lv450 does not start

as soon as I return home, I photograph everything, thanks for the help

[Moddingscreen]

Re: lg tv 42lv450 does not start

Here is the pin situation:
ERROR 0V
PWM 0V
NC 0V
DRY ON 0V
VSYNC 0V
3.5V 3.5V
24V 0V
PWR ON 0V
I forgot to tell you that the relay does not attack

[dskall]

Re: lg tv 42lv450 does not start

What are voltages when you push power button?

[freakaftr8]

Re: lg tv 42lv450 does not start

What is voltage at the main capacitors on hot side of power supply upon pressing power button?

Link PWR_ON to 3.5v with a 1 ohm resistor on th e P201 connector. You should have relays click and energize power supply. Check capacitor voltages again.

[Moddingscreen]

Re: lg tv 42lv450 does not start

I measure 1.9v and 320v in attached photo

[Moddingscreen]

Re: lg tv 42lv450 does not start

connected resistance as mentioned, the TV now turns on appears the logo lg and then the display remains black

[freakaftr8]

Re: lg tv 42lv450 does not start

Screen remains black because you also need to jump PS on to DRV on. If that works and turns on backlights, your mainboard is bad.

If back lights come on do you have a blank picture?

[Moddingscreen]

Re: lg tv 42lv450 does not start

what is ps? I have DRV-ON where do I have to connect it?

[freakaftr8]

Re: lg tv 42lv450 does not start

Also to the 3.5v

[freakaftr8]

Re: lg tv 42lv450 does not start

Nevermind. Your picture shows that it's lighting up is it is stuck on the logo?

* Before you had mentioned that it was just blank I didn't see you added the fact that you have a logo and backlights.

[Moddingscreen]

Re: lg tv 42lv450 does not start

then, without connecting DVR ON at 3.5v the TV turns on shows the logo and then remains black without backlight, now I try to connect the DVR ON at 3.5v and I'll let you know

[Moddingscreen]

Re: lg tv 42lv450 does not start

I'm sorry I changed after the message, proceed with connecting the DVR ON to 3.5v?

[freakaftr8]

Re: lg tv 42lv450 does not start

Yes try connecting DRV-ON With 3.5v also. It should cause of backlights to remain lit even with a blank screen if it's trying to blank out after the LG logo

[budm]

Re: lg tv 42lv450 does not start

You MUST disconnect the DRV-ON wire going back to the main board first otherwise you will damage the switched Transistor on the main board that is in the full on mode right now.
I always use resistor in case you make wrong connection or forget to disconnect the wire back to the main board first.

[Moddingscreen]

Re: lg tv 42lv450 does not start

in this way right?

[freakaftr8]

Re: lg tv 42lv450 does not start

Yes you will want to remove the drive pin from the connector at the main board side Before powering up

[Moddingscreen]

Re: lg tv 42lv450 does not start

with the connection as above, the TV turns on but does not show anything even the logo that I could see for 10 seconds before