Samsung UA46B7100WFXXY

[Aussie]

Hello everyone, I know this is only my second post but I do intend to spend some time on this forum and hopefully add as much information that I can..

I like to repair audio equipment normally but would like to learn more about TV repair.
In my travels today I picked up one of these TV's....
So far...Green screen, I cleaned ribbon cables and now have picture.
I now have horizontal white stripes across full screen, kind of like looking through lines..
So I re cleaned ribbon connections and seems the lines are a little tighter...
still not the problem...so I pulled power board and checked all caps with an esr meter...all test good....

After some more testing, it seems that picture is better when first powered on, then degrades shortly after, when components warm up...then I start to get vertical ghosting.....

would like to know where to start troubleshooting this TV...can anyone help?

[Aussie]

Re: Samsung UA46B7100WFXXY

Here are some Pictures of screen and boards for reference...

[Aussie]

Re: Samsung UA46B7100WFXXY

I know the power board is loaded with cheap caps and I would like to replace these., although they all test ok.....But I am hesitant to move forward at this stage until I have more information regarding this model....

[Aussie]

Re: Samsung UA46B7100WFXXY

No clues ?

[tom66]

Re: Samsung UA46B7100WFXXY

We have seen this before on this forum. It is a bad LCD panel. No fix is currently known. Sorry.

[Aussie]

Re: Samsung UA46B7100WFXXY

If that is the case, would the same problem not present its self all the time ? picture gets worse about a minute after powered on

[tom66]

Re: Samsung UA46B7100WFXXY

No, some LCD panel faults can get worse as a set warms up.

[mmartell]

Re: Samsung UA46B7100WFXXY

Try cooling spray on the boards one at a time. Obviously if you see an improvement you've narrowed the source. And if not, well, tom's already stated the alternative...

As a last resort you could tear it down to the tabs but I'm not sure tab bonds manifest in this way.

[Aussie]

Re: Samsung UA46B7100WFXXY

Hmm ok, well I hope its not the screen...I would still like to be sure though before I discard it.....
So this morning I powered unit up again via power board switch and the green screen returned....powered off again and re checked ribbon, then back on via power board...still green, I then turned it off and back on again via power button and got picture back....still with other issues shown....

I have now been over boards with electronic freeze spray with no changes....is there a service manual for this this so I can check voltages?
Are the pictures I have shown clear enough?

[Aussie]

Re: Samsung UA46B7100WFXXY

As a last resort you could tear it down to the tabs but I'm not sure tab bonds manifest in this way.

Could you explain what you are talking about here? or possibly direct me to another thread on this topic?

[Aussie]

Re: Samsung UA46B7100WFXXY

just some more info, after again removing power supply board and rechecking caps, resistor values and diodes I then re installed....
after reinstalling the green screen returned again. i shifted it off the bench to do something else at that point.
when i set up again i didn't realize at first i had placed set upside down....I didn't bother flipping as i only intended to test voltages...But it came back to a picture again.

I then unplugged again and flipped the right way up, when i turned it on i had the clearest picture ive had yet...

Look, I know you guys know your stuff, but is it possible I have a board issue here?

I then took the tv inside for the first time and plugged in PAL antenna, the television really struggled to get a decent signal...barely able to get a channel where my other tv a Panasonic Viera has no problem at all....

also checked internet Ethernet line in, all working well...

but still have the lines.....

[Aussie]

Re: Samsung UA46B7100WFXXY

Although there is information on the Power supply board regarding voltages, I am unsure what to match to the rails leaving that board....
I did however note several at 5.2v, couple at 12v BUT, one at 2.2 v...this seemed odd to me?

[Aussie]

Re: Samsung UA46B7100WFXXY

We have seen this before on this forum. It is a bad LCD panel. No fix is currently known. Sorry.

If this has been heavily discussed on this forum before and I am trying to flog a dead horse here, would you mind linking me to the thread?

[Aussie]

Re: Samsung UA46B7100WFXXY

This is how good the picture was before i took it into the house.....it was clear like that for a good ten minutes...still very fine horizontal lines though....if you stand back its not obvious....

[mmartell]

Re: Samsung UA46B7100WFXXY

Could you explain what you are talking about here? or possibly direct me to another thread on this topic?

https://www.badcaps.net/forum/showthread.php?t=25371

[mmartell]

Re: Samsung UA46B7100WFXXY

Even if this were a main board issue there is only a small chance of repairing it due to its complexity. If you want to chance it order up a new (replacement) board.

[Aussie]

Re: Samsung UA46B7100WFXXY

Even if this were a main board issue there is only a small chance of repairing it due to its complexity. If you want to chance it order up a new (replacement) board.

Thanks for the link there, that was helpful...I will look at that next...

As far as ordering any new boards, I will not be doing that unless I am certain I have located the problem, I normally repair audio circuit's. I've not done much TV or surface mounted board work though and I am still a learner....

Currently back to Green screen!

[Aussie]

Re: Samsung UA46B7100WFXXY

We have seen this before on this forum. It is a bad LCD panel. No fix is currently known. Sorry.

G'day Tom, Do you mind if I ask what is "this" problem?

[Aussie]

Re: Samsung UA46B7100WFXXY

I reset all ribbon to T board and got picture back...hoping to possibly improve again I reset them again, and now back to green screen....
Its a bit of a head ache handling a 46 inch tv.....
I would be very grateful if someone could be of more help...

[tom66]

Re: Samsung UA46B7100WFXXY

G'day Tom, Do you mind if I ask what is "this" problem?

Visible image with lines on screen. Common fault

https://www.badcaps.net/forum/showth...ight=ue46b6000
https://www.google.co.uk/search?q=ue...ml%3B350%3B263

Other panel faults with these models:
https://www.badcaps.net/forum/showth...ight=ue55b7000

All Samsung LED-LCD TV is hit and miss, bad panels are common, so I avoid them now.