Fixing LG's LCD TV - Power PCB

[gogetax1]

PCB 68709D0006B


i have this problem with my PCB
the LCD is not turning on, but i do hear the Relay turning on and off every second. (relay is the black box at center right from that screenshot i gave you, its the one that glued with blue capacitor)
i desoldered the relay, and i checked it under 18 volts, and it does works fine.

so for me, it looks like im not getting stable DC voltage out of some components to replay.

thats what i wanted to know.. what components can cause the problem like i said earlier; turning on and off every second, not getting stable DC voltage to turn on the replay.
Capacitor? or maybe a diode? if its capacitor, then what kind?
cuz its sandwitch pcb board, i cant use the leads to find the problem

 

[gogetax1]

here is a small hint that i disconvered only by the ticking sound of the relay..

it looks like the relay opens and closed when it riches the 18 V but then closing back to about 1 sec.

i managed to build without osciloscope this time line.
**broken link removed**

 

[Sangoma]

Samsung had huge problems with the same symptoms, through a wide range of models. All was the same problem, cheap Chinese capacitors.
Replace the capacitors in the psu and they turn on and work fine again.

Starts of having to push the on button on the remote many times, and gets worse until it won't turn on.

If it is the same problem, it may help.

 

[bryan]

Samsung had huge problems with the same symptoms, through a wide range of models. All was the same problem, cheap Chinese capacitors.
Replace the capacitors in the psu and they turn on and work fine again.

.

A ESR meter can be your best friend at times like this.

 

[baileybum1234]

From my limited experience the relays click for a reason.

There should be an IC that checks voltages around the board and things.

If there is something wrong ie. component shorted the IC will not let the relays close fully until its repaired.

There are a few things you can check like standby 5v firstlywith the PSU in and out the TV. But like I said Im no expert but it just might give you a lead to do some research.