LG 55B6P OLED No image/sound

[Diah]

Re: LG 55B6P OLED No image/sound

yes so now we have the micon reset complete.
now turn it on and check on USB 1 2 3 do you have 5V?

[blkrx7]

Re: LG 55B6P OLED No image/sound

Turned on
0v on USB 1, 2, 3

[Diah]

Re: LG 55B6P OLED No image/sound

okay... you need to check on the socket P2500 wich come from PWB pin 3 4 5 6 had 24V or less

[Diah]

Re: LG 55B6P OLED No image/sound

also locate IC2305 (DC to DC )on MB and shoot clear photo of it and round parts such IC4301 IC4400

[blkrx7]

Re: LG 55B6P OLED No image/sound

P2500
24.56 on Pins 3, 4, 5, 6

New IC's attached

[Diah]

Re: LG 55B6P OLED No image/sound

so if you check IC4301 IC4400 pins could u find 5V ?

[blkrx7]

Re: LG 55B6P OLED No image/sound

IC4301
IC4400
1 -> 5v
2 -> 0v
3 -> 0v
4 -> 3.3v
5 -> 0v
6 -> 0v


IC2305
15,16,17 -> 12v
18 -> 0v

These aren't easy to measure, if something looks way out, yell.

[Diah]

Re: LG 55B6P OLED No image/sound

so 2305 working..
now i want you to remove the socket on the T-CON driver which it come from PWB 24V socket.. turn on and give notice on Audio optic lit red or not... give time 1 minute

[blkrx7]

Re: LG 55B6P OLED No image/sound

Unplugged from wall
Removed P202 from Power supply
Plugged into wall
Turned on
Waited 1m

No Optic LED light

[blkrx7]

Re: LG 55B6P OLED No image/sound

Strange, usually I get 1v on the 24v rail (measured on power supply).

When 202 is unplugged, I get 0v

The fuse on the tcon (measured good) reads 1v on either side. I presumed it was the power supply sending that 1v, but it seems like it's being backfed somewhere on the tcon.

[Diah]

Re: LG 55B6P OLED No image/sound

sure if 202 unplugged you will get 0V on t-con side but 24 on PWB
and if its plugged how much it read on T-CON side?

[blkrx7]

Re: LG 55B6P OLED No image/sound

1v

202 unplugged
Power supply output pin 0v
Tcon power input pin 1v

202 plugged
Power supply output pin 1v
Tcon power input pin 1v

The 1v is coming from the tcon. May not be relevant but surprises me to see any voltage on that pin at all while it's unplugged.

It's actually 1.336v, very strong, very consistent.

[Diah]

Re: LG 55B6P OLED No image/sound

the main boards didn't sent signal to turn on the panel 24v rallies on PWB.

[blkrx7]

Re: LG 55B6P OLED No image/sound

Yep, I can bridge the P201 pins 24 (drv_on) & 17 (stby) and confirmed the power supply outputs 24v (tcon/mb unplugged from power supply).

That signal is not getting sent from the mainboard.

Would you like me to bridge it while it's connected to the mainboard/tcon?

[Diah]

Re: LG 55B6P OLED No image/sound

can you show the pins print label of the sockets which goes from PWB to MB?

[blkrx7]

Re: LG 55B6P OLED No image/sound

See attached

[Diah]

Re: LG 55B6P OLED No image/sound

Yep, I can bridge the P201 pins 24 (drv_on) & 17 (stby) and confirmed the power supply outputs 24v (tcon/mb unplugged from power supply).

That signal is not getting sent from the mainboard.

Would you like me to bridge it while it's connected to the mainboard/tcon?

you can do it but only in this way... if pin 24 are drv_on trace the cable of it which it come from MB.. cut it in the middle then bridge pin 24 with stb put back socket 202.. and turn on and put your eyes on the screen and the audio optic if its turn red

BTW: of course we are talking on the bridge only at PWB side

[blkrx7]

Re: LG 55B6P OLED No image/sound

Unplugged
I removed pin 24 completely from p202, so it would not connect to power supply.
Jumped 24/17 on the power supply
Plugged in
Turned on

I have 24v at the tcon now
No optic LED or anything on the display

[Diah]

Re: LG 55B6P OLED No image/sound

screen black? play your PC hdmi

[blkrx7]

Re: LG 55B6P OLED No image/sound

Laptop plugged back in, still nothing on the display, no voltage at usb.

Laptop still reports back it's plugged into an LG display.