KDL-40W4100 Flickering

[Jackching]

I get a black flicker on the screen regardless the input. It doesn't matter if a HDMI cord is plugged in or not, you can still see the flicker. It used to come out of it after about 20 minutes of viewing but now it seems to always stay there. Here is a video: https://www.veed.io/view/26c0999a-e3...bc?panel=share

[nomoresonys]

Re: KDL-40W4100 Flickering

no video there, just some audio.

[nomoresonys]

Re: KDL-40W4100 Flickering

go ahead and heat up those electrolytic caps with a hairdryer, start with those 4 by the connector there, heat them up for a few minutes, then try the tv, don't wait til it cools down, try it while its still hot, see if there's any change.

[Jackching]

Re: KDL-40W4100 Flickering

go ahead and heat up those electrolytic caps with a hairdryer, start with those 4 by the connector there, heat them up for a few minutes, then try the tv, don't wait til it cools down, try it while its still hot, see if there's any change.

Are you serious or are you wanting a picture of the boards? If you're serious, the four caps on the PSU?

[nomoresonys]

Re: KDL-40W4100 Flickering

what part of the suggestion are you having trouble with, is there 4 electrolytic caps by the connector on the psu or not. Pictures should always be the first thing posted when there's a doubt about what the issue is, my crystal ball is broken so I can't see what you see there.

[Jackching]

Re: KDL-40W4100 Flickering

what part of the suggestion are you having trouble with, is there 4 electrolytic caps by the connector on the psu or not. Pictures should always be the first thing posted when there's a doubt about what the issue is, my crystal ball is broken so I can't see what you see there.

Ok I heated the 4 caps by the PSU connecter then hooked it back up. It seems to be way better then what it was. Im noticing if I move the tv around though that it seems to make it flicker some but i find it's only happening half as much after I heated them. I tested the caps with a cap tester and they all seemed to test good.

[nomoresonys]

Re: KDL-40W4100 Flickering

if moving or tapping lightly on back of tv effects the picture it could be a bad connection in the backlight circuit or a bad solder joint on bottom of psu board, maybe look them over very closely, magnified if possible and reflow any suspect solder joints, careful not to bridge any, examples of bad joints there: https://www.google.com/search?q=bad+...ih=607&dpr=1.5

[nomoresonys]

Re: KDL-40W4100 Flickering

as for the caps, if the picture goes back to being worse and is better when they are warmed, I would switch them out, might be the only issue, just to eliminate them as the problem, why not, they are actually only meant to last about 10 years, even tho some are still good after 50 years.

[Jackching]

Re: KDL-40W4100 Flickering

if moving or tapping lightly on back of tv effects the picture it could be a bad connection in the backlight circuit or a bad solder joint on bottom of psu board, maybe look them over very closely, magnified if possible and reflow any suspect solder joints, careful not to bridge any, examples of bad joints there: https://www.google.com/search?q=bad+...ih=607&dpr=1.5

Okay, I already had the PSU out and checked for bad solder joints but can go over it again. Any chance of it being a ribbon cable? When i touch right above the top right ribbon cable, it seems to flicker. Are there any videos on getting the bezel off this tv to access the ribbon cables? I can get the top part off but dont want to start taking everything apart without knowing what im doing.

[nomoresonys]

Re: KDL-40W4100 Flickering

its ccfl tv, they're easier to work with than a lot of the later made led tvs, should be pretty straight forward for tearing it down, suppose you want to check the tab bonds.

[nomoresonys]

Re: KDL-40W4100 Flickering

another thing to try, go into display settings and set Random noise reduction to off.

[nomoresonys]

Re: KDL-40W4100 Flickering

plus the simple reset, with tv unplugged hold power button on tv in for 30 seconds, plug tv back in and try it, if you havent already.

[Jackching]

Re: KDL-40W4100 Flickering

I turned off noise reduction and did the reset and still the same thing. When i lean the tv ahead or back at certain angles, it will work fine until i move it a touch either way then it will start flickering again. I went over all of the PSU another two times with a magnifying glass and it looks as good as new.

[nomoresonys]

Re: KDL-40W4100 Flickering

Ok, seems like possible tab bond issue: https://www.youtube.com/watch?v=purk_SyiT44&t=5s

[nomoresonys]

Re: KDL-40W4100 Flickering

here's a super low tech tab bond fix, whatever works right: https://www.overclock.net/media/no-title.4154762/full

[Jackching]

Re: KDL-40W4100 Flickering

Im thinking tab also. That last option with the clamp is funny lol. Ill try stripping it down a little further to access the tabs then.

[Jackching]

Re: KDL-40W4100 Flickering

Ok, seems like possible tab bond issue: https://www.youtube.com/watch?v=purk_SyiT44&t=5s

Ok it is indeed the tabs. It is the one on the left. Im just not sure the best way to secure it where i need it. I dont want the tape to fall off or something after i get it all back together. Any suggestions on holding it where i want it?

Edit: So when the metal frame was put back on, that's when the picture would cut out and flicker. I needed a way to keep the tab out when i put the frame back on so i found some sill plate gasket for houses and cut a strip off it. I had to stog that behind the tab to keep it out when i pushed the metal frame back on. I can move the tv and tap the back of it now without it even flickering.

[nomoresonys]

Re: KDL-40W4100 Flickering

you just need a little steady pressure on that, see where you hold it lightly down and it gets good contact and screen clears up, just put your shim over that, that nice metal frame will hold it in place, you can tape whatever you use as a shim in place if you want: https://www.youtube.com/watch?v=zqcdTNoOoN0

[nomoresonys]

Re: KDL-40W4100 Flickering

here's a tip, after you put the screws back in your metal frame, try the tv to make sure there is no lines, sometimes if the screws are a little tight you can get lines on the screen, then you would just loosen the screw a little, doesn't happen a lot but I have run across the issue.

[Jackching]

Re: KDL-40W4100 Flickering

So anyway when the frame was on i could notice the gasket i put in behind the display when the screen was turned on so i went to move the gasket and must have tore the ribbon or something because now i cant get it back to how it was. Also there's a line going down the screen. So thats all she wrote. To the dump it goes