Thanks for the inputs everyone
The TV I'm trying to repair is a philips 47PFL4606H/12 equipped with a 47" IPS panel from LG (lc470wuh-scb2). It was manufactured in Oct 2011.
Here is a picture of the power board (715g4546-p03-h20-003e)
The red arrow shows the location of the 2 currently removed capXon caps.
The dirt one was the furthest away from the transistor/heatsink:
Also as already mentionned at the beginning of the thread the tactile board is another suspect for causing the shutdown.
Long story short (well, I'm not good at that
), this TV was meant to go to the bin a few years ago. Someone from my family brought it back from friends (they had it already hanging outside waiting to be trashed...) so I could have a look at it.
When I tried it, it was powering up but with the OSD flashing on screen, the sound volume going up alone, the channel switching up alone too, and it could also go into standby alone IIRC.
I understood it was most likely a faulty tactile panel and decided to try some "voodoo" to fix this. I had the idea (or maybe had read about somewhere) to stick an aluminum foil on top of the front tactile panel and... it worked. With the right positionning the OSD stopped flashing and channels stopped changing, the TV was not going into standby, and the IR was working so I could access all the TV menus. I disabled the internal sound (this was still causing an OSD message) and added external speakers and the TV was usable again.
It has been working nicely like that since 1 year or 2 until this summer when it started switching off after a few minutes. Repositionning the aluminum foil doesn't seem to prevent the shutdown, hence why I suspected it could be a power supply issue with the high temp we had this summer and the age of the TV.
So another question: do you know if such tactile panel can be by-passed ?
I haven't tried disconnecting it from the mainboard to check what would happen.
The IR receiver is on the same board and there are 2 connectors going to the mainboard.
Is it possible to disable the tactile part while keeping the IR receiver ?
Or disconnect this tactile panel completely and do a mod somewhere on the mainboard to have a ON/OFF switch ? I don't need anything else as the sound and channel switching is controlled through an external dvb-t box anyway.
I have checked yesterday and couldn't find this tactile board to buy (I found 1 on ebay but will ship only to germany. And I'm not sure it would fix the issue).
Here are pictures of the tactile panel board (715G4958-K02-000-004B) and the mainboard it is connected to (bottom left connectors):