Samsung UN75JU7100

[cbearden]

Hi everyone. I have the above TV that had washed out colors on half of the screen. I replaced the TCON board, and now I see this on the screen.
I get no response on my remote now, except for power on/off.
And this little blue arrow flashes back and forth.
Anybody ever seen this before?
from what I can tell, the colors on this little bit that's displayed seem to be good now after the TCON board was replaced.
Thank you.

[budwich]

Re: Samsung UN75JU7100

disconnect one of the tcon to panel cables (with power off) and check what happens. Do the same "test" with the other disconnected. This may check if there is a panel issue.

[cbearden]

Re: Samsung UN75JU7100

Thank you for the suggestion. I'll try that and see what I get.
This is a pic of my original TCON board before I replaced it.
My replacement (used from ebay), had the correct model # on it,
but instead of PC18, it said PC23.
I didn't know if this could have been a possible mismatch with my mainboard or not.

[budwich]

Re: Samsung UN75JU7100

other things that you might try. Is it connected to the internet, either via wire or wireless. On some sets, people find that a system might hang trying to connect, they have removed the wireless card (if equipped) or removed the ethernet cable.

I can't make much out from your first picture BUT if I am seeing things correctly the right side of the display is "compromised" and potentially indicates a "bad panel". It might be saveable but do the suggest "cable remove" tests that were suggested and go from there.

[cbearden]

Re: Samsung UN75JU7100

It isn't connected to anything, internet, HDMI, etc.
I was simply trying to get the built-in TV menus to work after I replaced the TCON board.
Everything else worked fine on the TV before I swapped the TCON board out, with the exception of the washed out colors.
I could go into the TV menus, play a movie, etc, even though the colors looked distorted.
Now, the TV will only display this 1st image and won't do anything else no matter what I press on the remote.
Sorry for the fuzzy picture.
It looks a little fuzzy to me on the TV as well.
It seems to be a small green box with upside down the word samsung on one side, a small blue arrow flashing back and forth to the other larger blue box.

[cbearden]

Re: Samsung UN75JU7100

This looks like it might have something to do with the mini connect hub.
But I already tried hooking it up with the same result.

[R_J]

Re: Samsung UN75JU7100

That is not the t-con board, that is the Main Subcon board, for model UN75JU100FXZA (version US02)
Maybe the board you recieved is for a different version panel or maybe its just defective, I would install the original and see if you can get back to what you had originally.

[budwich]

Re: Samsung UN75JU7100

you might be wise to post more pictures of the layout at the back of the set. Is this set a "one connect" type set (I didn't get that from the quick search)... but if that picture is the "one connect" startup page requesting that you connect the "one connect box" then it would appear as RJ indicates perhaps replace the main card with the wrong card.... if it is NOT a "one connect" set.

[R_J]

Re: Samsung UN75JU7100

It could be that the fault IS with the t-con, so remove the "new" subcon board and install the original subcon board. that should get you back to the "washed out colors on half of the screen" then troubleshoot the t-con or possible panel problem.

[cbearden]

Re: Samsung UN75JU7100

ok, apparently, I'm an idiot!
I thought I knew what the TCON board was, but evidently not.
I've taken new pictures of the entire rear of TV, with the original subcon board back in place. And then I took pics of what the picture looks like, and it now works again. Apparently the other subcon board I purchase wasn't the correct one for this TV, or is bad.
Regardless, maybe this will give me a fresh start with this.
And please help me confirm that this board at the very bottom of the TV is in fact the TCON board. (As i'm smacking myself in the face!)

[budwich]

Re: Samsung UN75JU7100

there you go.... :-) Anyway, my guess is your "panel" is bad. The drivers on one side appear to have an issue... if the line in the middle isn't part of the picture and the darkness on one side is always there. You might be able to still save the panel by removing the bad side tabs. Hopefully, you can locate them easier than the tcon... :-)
Tons of threads about bad side tabs and the method for "saving" the set by their removal.

[cbearden]

Re: Samsung UN75JU7100

Understood. I'll work on that next. Thank you all for your advice!

[cbearden]

Re: Samsung UN75JU7100

I already had a replacement TCON board ordered since I didn't get it right the first time.
So, I figured since the tab removal procedure was a last resort, I would wait until I swapped the TCON first.
After that, I poked around on the different ribbon cables hoping it was an intermittent or bad connection. No dice there.
And these pictures are a better look at the different menus I see.
Some are from a RGB test screen in the menu.
I mainly just wanted to get a confirmation from someone that after seeing these pictures, and what I've troubleshooted/swapped out, that the tab removal is my only/last option here.
Thanks.

[dick_barton]

Re: Samsung UN75JU7100

It certainly is looking very much like a side tab issue.

[budwich]

Re: Samsung UN75JU7100

hmmm... not sure based on those pictures as the darkness is there but I don't any horizontal lines which would be a "reasonable sign" and a tab / panel failure.

What's the history of the TV? (ie. how did it get into this "broken state")

In your previous pictures, that last one showing the tcon (2 cables in 4 out).... note there are cable connectors on the other end of those 4 cables... have you checked them for proper seating / reseating?

[cbearden]

Re: Samsung UN75JU7100

I got this TV from a friend of mine. He originally bought it from BestBuy, who installed it. Once, when I was working on it, we proceeded to do a firmware update. It hung during that firmware update and never recovered. Samsung support sent out techs multiple times and finally ended up replacing the mainboard on it. After that it worked just fine for the past 2 years I believe. He recently had a professional moving company move all of his belongings. The TV worked fine before they moved it. And after the move is when the problems started and he didn't want it anymore, so I picked it up from him. When I first saw it at his house, it had more screen artifacts in it, I'll just call them "ghosting" colored lines move across the screen while you were on the TV menu.
After I picked it up, brought it home, I took it apart and unplugged and replugged every cable, thinking it was just a loose cable from the past move.
Since I've replugged the cables, I don't see the colors move across the screen anymore at least.
I'll try rechecking all of the cables and also try putting some slight pressure on them to see if this could still be a connector issue.
Could this possibly be some of the led circuits on the one half of the screen? I haven't tried anything with them yet, but did notice what I though was the led power connectors coming off the PS board.

[budwich]

Re: Samsung UN75JU7100

the led power connectors would only cause an issue with the brightness of the screen. The "blue picture" shows problems with words and other things on the screen.

You would be wise to take a look at the "dark side" of the set and check the bonded tabs along that side of the panel looking for tabs that look "damaged" (heat, pinched, etc). Further, there is usually a small ribbon connector at the bottom corner of the set which connects the bottom edge boards to the side edge boards. That ribbon cable might not be seated properly or even disconnected. That could explain the darkness plus other effects.

I am still thinking that it is a tab problem on that side... but the checks that I suggest may help narrow it down more.... as it is also possible that an SMD device (capacitor or resistor) on the bottom edge board has a problem near the corner / interconnecting cable that I mentioned.

[Andrew F. Ali]

Re: Samsung UN75JU7100

The pictures look like a backlight problem but I think they were tested as good? Yes a capacitor (ceramic) could be pulling down the voltage on the panel boards too.

[cbearden]

Re: Samsung UN75JU7100

I will plan on spending some time to search for these tabs on the side of this TV. So far the only thing like this that I've found was across the entire bottom.
According to what I've seen in some other posts about this, I might have to take the metal casing off the panel in order to find the tabs?
There's nothing on either side that I can find yet.
And I haven't done any testing on the backlights yet.

[budwich]

Re: Samsung UN75JU7100

the side tabs are usually only visible from the front. You have to take the bezel / plastic frame off.