60" LG 60PB690V relay clicking issue

[DodgyTech]

Hi everyone,

I require some help with my TV. The TV standby light blicks on and off with a clicking sound (relay?) from the back. After I opened up the TV, I set about troubleshooting by unplugging the boards to try and isolate the problem. My troubleshooting suggests that the logic board is causing the issue, but it could entirely be the YSUS board which is only activated once the logic board is connected.

I have recorded a video which I thought would be an easier way to explain the problem and show the boards at the same time.

I would like to try and identify the faulty component if it's in one of the boards that are at the back rather than purchase a new board (if we can work out what it is).

I have a multimeter and have a soldering station so I can have a go at testing/replacing components as required.

Video link (3min 41sec): https://youtu.be/8IULh7uoGXs

Thank you all in advance


EDIT:
Power board part number: EAY63168603 (PCB: EAX65359531, Rev: 1.0)
YSUS board part number: EAX65331001 (2.0)
ZSUS board part number: EAX65331101 (2.2)
Logic board part number: EAX65399305 (1.0)

List of the sites/pages I visit in my research:
https://www.badcaps.net/forum/showthread.php?t=72699
https://www.badcaps.net/forum/showthread.php?t=66297
https://www.youtube.com/watch?v=egNSzoH4tRc
https://www.youtube.com/watch?v=SfXf58shH-o

[Biruslapio]

Re: 60" LG 60PB690V relay clicking issue

This board is not always easy to repair, but first you need to find where the fault lies, if there's any shorted component on Y-SUS, Z-SUS, you know it.

Test if the buffers are ok, example video:
https://www.youtube.com/watch?v=3Oq2MsU0XOQ

[DodgyTech]

Re: 60" LG 60PB690V relay clicking issue

This board is not always easy to repair, but first you need to find where the fault lies, if there's any shorted component on Y-SUS, Z-SUS, you know it.

Test if the buffers are ok, example video:
https://www.youtube.com/watch?v=3Oq2MsU0XOQ

Thanks for the video, I tested one of the two buffer boards and didn't find any continuity.

In the middle of doing this, I connected the YSUS board without the buffer boards attached and found the clicking still persisted. That leads me to think it's not the buffer boards but the YSUS board itself.

Any tips on how to find the fault if it's within the YSUS board?

[Biruslapio]

Re: 60" LG 60PB690V relay clicking issue

Take the Z and Y boards and measure all the transistors, most important are the bigger SMD ones on the back, and the ones mounted to the heatsinks, any short = bad.