Samsung PN60F8500 screen glitch/flicker

[itelite]

This one is driving me nuts. Any ideas what is doing this? Nothing visually damaged on any board. Does not appear to be heat related as it happens almost immediately. Firmware up to date and have already reset to defaults.

Happens on all inputs as well as the scrolling test pattern.

The entire screen glitches including the OSD.

Video below.

https://youtu.be/mTMWR8c7pUQ

[tom66]

Re: Samsung PN60F8500 screen glitch/flicker

Main board.
Post a picture, we can try a diagnostic mode.

[itelite]

Re: Samsung PN60F8500 screen glitch/flicker

[tom66]

Re: Samsung PN60F8500 screen glitch/flicker

Jumper pins 3 and 4 of the block marked 2CN2014_LO (it has four holes, two marked NT, two marked PAL, jumper pins 3 and 4 of this with a wire)
Then plug in the TV and see if you get test patterns and see if they are stable.

[itelite]

Re: Samsung PN60F8500 screen glitch/flicker

Was good for maybe a minute. then these glitchy lines appeared, then went away, then came back an have been there since. Im guessing they are not part of the pattern.

Not doing the flashing or screen glitching in this mode though.

[tom66]

Re: Samsung PN60F8500 screen glitch/flicker

Your vertical lines are probably a bad panel so that's not good. I see a lot of F8500 with vertical lines due to panel failure.
But this has confirmed that the main board is bad as well.

[budwich]

Re: Samsung PN60F8500 screen glitch/flicker

clean and reseat all cabling going to and from tcon (ie both panel and main board cabling).

[itelite]

Re: Samsung PN60F8500 screen glitch/flicker

:EDIT: Disregard. Put yet another chip on it, back to all 4 sources working and no glitch yet, but this is how it happened the first time ha



Well its gets more strange. This was the one i replaced the HDMI mixer chip in a few weeks ago. I decided since i have a few of them i would pull the chip off the board and run the test patterns again. No lines, no glitching.

Put a new chip on, ran test patterns, no lines, no glitch.

Took out jumper for test patterns, now it is back to the original issue of no signal on some inputs, sometimes. That is to say i can plug a device into HDMI1 - signal. Not touch that cable at all, turn tv off, turn back on, no signal. same goes for other ports and it seems random. Glitching will still happen on HDMI inputs when they get signal.

I see there are many repair services for this main board, mentioning the HDMI issue as symptom. Something that anyone has come across? Any thoughts on what component on this board could be at fault?

[tom66]

Re: Samsung PN60F8500 screen glitch/flicker

It's likely the soldering on the main processor. If you are feeling confident you could remove and reball the processor but you'll need to locate the stencil for it. It's a pretty complex job and not for an amateur.