No Picture nor sound nor anything but power led is working

Hi. Ive been using a 50-inch plasma Sansui TV as an additional screen on my laptop (mostly for gaming) for quite a while but now something stopped working. The power indicator on the TV turns from red to green when switched on, but NOTHING else happens. Even when no other cables but the power cable is connected this happens and I cannot even get the INPUT select or anything else to show on the TV.

I doubt the issue is with my laptop since I can see it detects the TV when turned on as the TV is set as my main display in this configuration. I tried using other HDMI cables too but to no avail - I say this though it might be irrelevant since the same things happens with nothing connected as mentioned earlier.

Another thing I noticed - its a rather old TV, and usually when I switch it on, I can hear one or two “clicks” in the TV as its turned on. The power indicator still goes green but I am not hearing those “clicks” anymore.

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Photos: first attempt with bad camera - will send better soon - hopefully this will tell you guys something?

Backpanel Removed - overview:

• New Photos ***

INSIDE LABEL:

FUSES:

@oldturkey03 @jayeff

UPDATE:

The replaced fuse is still working after first couple of tests (so it has not re-blown, yet). That might be important. Another "pattern" I now recognized for the 1st time after testing with the open panel, is that the "clicking" of the relays I mentioned originally, I can now see that on the board indicated in the image below, those click are accompanied by a smaall green led going on and off with every click. BUT this happens only once after the power has been disconnected from the mains completely. If I just switch the TV on and off with power button, the clicks do not happen again...

Also confirmed that results are exactly the same if I test with or without hdmi connected. Point is after the fuse replaced (and working still) the original issue is still unsolved (or just partially solved?)

@jayeff @oldturkey03 & anyone...

This is the progress I made thus far. I opened up the panel, then I disconnected all boards from power supply board and check voltages - all were good. I then reconnected all boards to the power supply board. Tested it - obviously nothing has changed and so just again the clicking sounds, no picture.

Then decided to disconnected all the boards from the psu board one at a time only to see if the clicking stops - and that process told me it was the Y-Sus board thats causing the issue.

Problem for me here in South Africa, shipping costs is about 4x the price of a replacement board - aliexpress, ebay, etc. - making it ridiculously expensive to replace the board - unless Im prepared to wait like 10 weeks or something then the total cost to me would be about 3x cost of a unit. Eish.

Whats failing on these boards? could iust be a loose soldier joint? or just a blown capacitor? something i might be able to fix/replace? I have a multimeter I just have no idea how to test for these things...