Sony KDL46XBR4.... a new "learning journey"

[budwich]

A friend of mine replaced this set with a 4k model. The driving force behind the decision was that the picture had an "issue" in the lower right corner that may or may not go away depending on amount time on and off and maybe a number of "on/off" cycles in a short time period. I saw it in operation and to me it looked like a "tab driver / bond issue". :-( Anyways, instead of carting it off to the recycle bin, I decided I would take a look at it since there was nothing to lose. I took of the back and "wth"... I couldn't recognize any "common" looking layout... no flat ribbon cables going from cards to the panel... ie. some "tcon looking thing". So I am stuck at square "zero" at learning the "lay of the land". There are cards like "FB1", "UB1", "AU", "GF1", "DF1", "H1-H4" in the block diagram. ???

Anyways, I am sure its will be come obvious once I dig further. The one main question that I have right now IS... with my limited sharp adventurer, I was able to unplug cables at various points and still power up the set WITHOUT causing any damage to the remaining cards / components. I know with plasma sets, there are some card "combinations" that have to remain connected or you cause your self "pain" (ie. take out other cards). Are there any similar restrictions with certain LCD manufacturers designs / layout that I need to be wary of before I start my "unplug, plug, play" effort. Basically, I was hoping to unplug the right half of the "display signal path" (ie. tcon) and see if the set reacts "better" and then focus on that side if that is the result.
Thanks for any guidance on this. I will post some pictures as soon as I can get the thing in some form of "stance" to allow photoing.

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

I got the thing upright (had to make my own stand as it was wall mounted in use). The attached photo is a picture of the display with a news channel that has a scroll bar along the bottom. As you can see in the bottom right corner, the scroll is "slow to build" along with a dark section in the middle. It is likely that it is a panel issue but I was hoping to learn more about the sony design layout as it appears to be quite a bit different from the other makers. Even identifying the tcon isn't obvious by just looking for large flat ribbon interconnect cables. I have to still get better access to the back and take more stuff off to expose the cards / layout.... plus get a better source display to show things better.

[freakaftr8]

Re: Sony KDL46XBR4.... a new "learning journey"

Driver tabs are located on the top of the panel. Take the frame bezel apart a push on the top right driver tab

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

Here is a couple more screen shots. One is for gamma setup (still). There is the center dark area but no obvious display issue in terms of horizontal or vertical "lining" associated with bad tabs / bonding. The other is a the title page (still) that again doesn't appear to show any "tab" lines but the dark area is obvious. Wondering if this might be more of capacitor issue at the edge boards... IF I can find them... :-)

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

Driver tabs are located on the top of the panel. Take the frame bezel apart a push on the top right driver tab

thanks... I was looking in the wrong place... :-)

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

So I started my journey... taking off some of the "cans" to get at boards. I can now see that the UB1 board forms the "start" of what I would think is some form of tcon function. The LVDS comes into it from the FB1 board. On the "other side" there are two "multi pin" flat "bridging connectors" much like tcon ribbon cables but just connector "plugs" that interconnect the UB1 to a GF1. It is significant effort to get the "can" off the GF1 as there is card holding plastic structure form holding other cards that is in the way. :-( so it will be a bit.

My question would be: On some of the sharp models that don't have side tabs, people have tried the "cutoff tap" type "save" at some of the tcon ribbons in "strategic point". Is this type of save possible on a Sony design? Where might that "strategic point" be?
As soon as I get more stuff off the back to give a better view, I will post a picture or two. Based on my view of the display, on the right hand side at even spaces (about 8-9 inches apart), there is a single horizontal line emulating from the right side... basically four lines which to me means it some common input line / driver "point" coming towards the side as opposed to a given driver for the side.... not know at this point how the side drivers are setup or even exist.

what are the chances (if the "tap cutoff" technique was applicable) that the "strategic point" might actually be those bridge connectors? and maybe just maybe... what are the chances that they might just need cleaning... based on the display of the gamma scale which seems to show that the overall panel looks "OK" in terms of "detail"?

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

Here is a picture of the UB1 board. Anyone know how to "disconnect" one or both of those "bridge connectors" highlighted? If its possible to disconnect one at a time, will this cause "disaster" to subtending boards or otherwise in this type of design?

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

As freakaftr8 suggested "go tabbing young man, go tabbing"... :-)
It appears people in this thread had success with "pressuring the affected tab" so that's where I am heading.

http://www.avsforum.com/forum/166-lc...ll-inputs.html

[Davi.p]

Re: Sony KDL46XBR4.... a new "learning journey"

This type of defect as i have seen in many YT videos and forums always belongs to faulty screen tabs, making pressure the image restores...

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

small question... can the top tabs be got at with the panel vertical on a stand... ie. will taking off the metal bezel cause the panel "layers" to drop / move if the panel is standing up?

[vinceroger69]

Re: Sony KDL46XBR4.... a new "learning journey"

i would lay the tv down as you dont want the weight of the lcd panel pulling down as could damage the tab bonds

[Davi.p]

Re: Sony KDL46XBR4.... a new "learning journey"

The panel matrix stay on a little guide but is keep still by the bezel, so if the top part passes ahead the bottom part the screen tend to come down and is no good, at least use 2 pieces of wide tape on the bottom sides.

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

ok... basically it took a couple of "flips". Once with face down to remove the internal support arms so that I could take off the top back "stay".... there was a wide piece of aluminized tape running from the top back "can" to the top metal bezel. Once that was folded back, then put the support arms back on and flip the unit now on its back. Then remove the 10 screws around the bezel and lift off. One issue I see immediately is the way Sony has positioned the "soft standoff material" to keep the edge boards away from the metal bezel. Some is place exactly at the "interlock fingers" that hold the bezel "electrically" to the ground of the back plates / "cans". However, the ones on the end two "fingers" are outside of the area leaving the potential for the edge boards to touch the bezel. I think sony had a "secret warranty" on the 46in sets of this model back about 2010 and I wouldn't doubt that it was because of the lack of "padding" to prevent this problem which would have been "catastrophic" if the board did touch.
Anyways, putting pressure on the last right tab at the edge board side of the tab allows the display to work normally so that is the issue with one. Just need to find some material to put in there to serve this purpose as I don't really want to use my finger going forward... :-) Looking at the tab, it doesn't look any different from the others, hopefully the driver isn't the actual problem but could be since the pressure on the tab actually causes the tab to bend outward which would mean "away from the back side of the driver" which might then allow the driver to get connectivity on its edges. Not sure how long it will last but the avsforum link was old and not too many reports back of status of sets at this time.

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

Last dum question, what do they refer to / call the material / padding that manufacturer's use for isolation in and around the bezel? Its like a tape, spongy / covered foam with adhesive on one side and some sort of which looks like almost EMI type "conductive" feel to it on the other.

[vinceroger69]

Re: Sony KDL46XBR4.... a new "learning journey"

budm has a post on his tab bond fix on a samsung tv i think with links to the material he used to fix the sets maybe worth a read of his thread

Edit here is the link
https://www.badcaps.net/forum/showth...b+bond+samsung

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

thanks. here is a picture of the pad that sony uses. It looks like foam with a covering so that stuff "slides" by it easily... when putting the bezel on. Note in the picture where it is and note I have put some plastic in the "interlock finger" for testing to keep the board away from the "finger". One "interior fingers" (two), sony put that padding on the board so there is "board", "pad", "bezel", then "finger" sandwich... no way for the board to touch. But at the two end "fingers", for some reason they moved the pads out to the edge as opposed to inside the "finger" area. Why not just add two more pads... sheesh, what manufacturer's will do to save some money / time.

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

I guess I am going to try and use some of this "high density" weather strip material. Its about the same height as the existing pads. Hopefully it will work. Put one also on the other end tab as it can also "weaken". I haven't figure out if I will do anything at the "fingers" yet. Note, these are NOT on the driver area but on the edge board side of the tab to hold the tab against the edge board conduction points.

[freakaftr8]

Re: Sony KDL46XBR4.... a new "learning journey"

That will probably work. Were you able to confirm that pressing on the tab straightens out the problem?

[budwich]

Re: Sony KDL46XBR4.... a new "learning journey"

yep... bezel is just loosely "wedge" on for now... letting it run to see if heating / run time changes anything but looks good so far. By "wedging", I mean you have to kind of "jam" bezel surface over the new pads because of the "uncompressed height" but still have to get on the right side of the "fingers" for the grounding / emi. I added some smaller pads near the fingers to ensure that the board can never touch that area.

Now all I have to do is find one small screw that fell somewhere but not sure where. I have turned the set over and upside down and nothing fell out.... hopefully it won't find its way to a "bad area"... :-(

[Davi.p]

Re: Sony KDL46XBR4.... a new "learning journey"

Hi, i'm unable to understand all your complex posts due to my english but i've noticed on the last 2 photos , right side, there's a very dangerous flat piece of metal near capacitors and on top of a plastic white piece, have you put it there ? It's really dangerous and it think is not original by Sony. If you have found a setup for the shim to keep the image good , i suggest you to not remount all because this has screwed me in a tv 'cause when tv moved to another room all mounted the defect became by new.