Sharp LC-60LE633U Panel Board and Tcon problems

[midnightg35x]

I have a Sharp LC-60LE633U that I picked up that has some damage to the Tcon board (Q6215 burnt), the flexible cables going to certain parts of the LCD, and a burnt capacitor on the LCD board that feeds the actual panel.

I found this bulletin that basically shows all of my burnt parts besides the one capacitor, but it does not really have an explanation of the root cause.

https://servicemanuals.us/sharp/tv/l...636e-sm17.html

I ended up sourcing a new Tcon and the Tcon to panel cables, but not the LCD to LCD cable. I used a multimeter and it is still good, but certain has signs of overstress. I swapped sides and everything still works on it even with the signs of overheating. I am fairly confident the burnt capacitor is the cause for the left hand 25% or so of the board to be blank. Unfortunately, I have no clue what capacitance and voltage the cap might be to try and replace it. Any suggestions?

The second issue I have is the same half of the board has 2 distinct green bands that more or less correspond to the location of 2 of the tab bond drivers. I do not see anything abnormal with the drivers, and using a thermal camera shows they really do not get any more hot than the rest. I do not know if this is an actual tab bond failure or something related to the previous failures. I have tried readjusting the Tcon to LCD cable, but to no avail. It does not seem like any physical manipulation can get the green bars to go away. Is it possible the replacement Tcon I got is defective? I find that a little hard to believe because the rest of the board seems to work, but I cannot swear to it. Any other thoughts on this? I would rather not throw the TV away, but I'm realistic about the possibility the panel is just outright bad.

[CapLeaker]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

It's hard to tell what that was. Could be a cap (brown) or an inductor (black). You have to look at the other opposite side on the board and find that same circuit.

[budwich]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

which "lcd to lcd" cable are you referring to? do you mean LVDS which goes between the main and tcon? checking it with a meter might not tell all about the cable beyond the fact that it can carry a "dc voltage" (ie. continuity).

[CapLeaker]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

which "lcd to lcd" cable are you referring to? do you mean LVDS which goes between the main and tcon? checking it with a meter might not tell all about the cable beyond the fact that it can carry a "dc voltage" (ie. continuity).

Put a load on it!

[midnightg35x]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

It's hard to tell what that was. Could be a cap (brown) or an inductor (black). You have to look at the other opposite side on the board and find that same circuit.

It is a capacitor. Looking on the other side is not an exact mirror image, but when I took it off it certainly looks like a capacitor. It has a gray body, not a black or darker color body like a normal resistor or inductor would. The issue I'm having is determining what to replace it with. I don't have any way to measure something below a nF and I don't really know if the voltage rating matters if it is anything about 16V.

which "lcd to lcd" cable are you referring to? do you mean LVDS which goes between the main and tcon? checking it with a meter might not tell all about the cable beyond the fact that it can carry a "dc voltage" (ie. continuity).

The LCD to LCD cable that connects the outer quarter part of the LCD to the inner quarter part of the LCD. The inner quarter part of the LCD also has the LCD to Tcon cable. I'll try to snap a picture soon if that description is not illustrating the point. I swapped the cables around and the other side works, so the cable should still be OK. Besides being able to handle any sort of current, what is your concern about the LVDS signal? As long as it did not burn open, I think it would have a real hard time changing impedance or overall length enough to disrupt an LVDS signal.

[CapLeaker]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

remove that blown up junk and clean the affected area. Turn the TV on and do a voltage measurement on those 2 exposed pads.

[budwich]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

my comment about the "lcd to lcd cable" was a question and the LVDS cabling was only a guess as to what you were referring to as "LCD to LCD cable" as it wasn't clear in the text or pictures.

Anyways, IF you are referring to the interconnection cable between the bottom edge boards and have swapped them around from the one on the other side and the problem remains, then it is unlikely to be a cable problem.

It is more likely that the edge boards in the area that you show have issues (and maybe further smd component problems). As suggested by capleaker, focus on those areas checking for either voltage or continuity across tracks / components.

Still further when you disconnect the interconnection flex cable between the two edge board on that side, what is the resulting display?

[midnightg35x]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

my comment about the "lcd to lcd cable" was a question and the LVDS cabling was only a guess as to what you were referring to as "LCD to LCD cable" as it wasn't clear in the text or pictures.

Anyways, IF you are referring to the interconnection cable between the bottom edge boards and have swapped them around from the one on the other side and the problem remains, then it is unlikely to be a cable problem.

It is more likely that the edge boards in the area that you show have issues (and maybe further smd component problems). As suggested by capleaker, focus on those areas checking for either voltage or continuity across tracks / components.

Still further when you disconnect the interconnection flex cable between the two edge board on that side, what is the resulting display?

Understood on the "lcd to lcd" cable. I was referring to the interconnection cables between the bottom connection boards. I didn't mean to sound defensive if that's how it came across.

If I disconnect that LCD to LCD cable, whichever section I disconnect just goes blank (black, not white). That is true for both sides. I found the issue with where that capacitor broke and will include the picture. When the capacitor blew, it took out one of the traces with it. I checked both sides of that trace for a short to ground, but found none. I included the other side's picture for reference. When I measure the broken trace (on the signal side) I read 15.5V. I read the same 15.5V on the opposite side that is working. So I guess that means I'll use an at least 25V cap when I fix it, but I still don't know what size cap to use. If it is just a decoupling cap, I'll probably just get the biggest cap I can easily find in an 0603 25V X7R cap. Does that sound reasonable? I'm thinking that this issue will fix that a quarter of my screen is blank, but it does not help me with the 2 green vertical bars on the inner quarter of the screen.

[CapLeaker]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

so you measured from the other side on each end of the cap?

[midnightg35x]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

so you measured from the other side on each end of the cap?

I verified on both sides (the blown cap side and the good cap side) that one end was connected to ground (you can see the fatter copper trace side in both pictures). Then with the black lead on ground, I measured the DC voltage on both the broken trace and the side with the cap still in place. Both were 15.5V. Based on what I see, a 0.1uF 25V-50V 0603 cap is possible. Does that value seem appropriate?

[budwich]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

you are worried about the cap... which is ok since it has "obvious" damage. However, if you look closer at your pictures, it appears, perhaps, that the tracks leading to those areas from the ribbon connection have some form of contamination across them... is this something that shouldn't be there... or is it the photo?

[midnightg35x]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

you are worried about the cap... which is ok since it has "obvious" damage. However, if you look closer at your pictures, it appears, perhaps, that the tracks leading to those areas from the ribbon connection have some form of contamination across them... is this something that shouldn't be there... or is it the photo?

I think it is a little of both. It was digitally zoomed so there is some weird artifacting, but I think what you are seeing is the aftermath of my probe tips checking for shorts. There were no other track to track shorts, but it probably slightly deformed the leads. I will clean that up before I power it back on. I'm not worried about those as I will get it resolved after I get a cap back on there.

[midnightg35x]

Re: Sharp LC-60LE633U Panel Board and Tcon problems

So I got back to this TV after some parts came in. I fixed the Tcon where I no longer have the green lines, but the same 1/4 of the panel still does not work. I looked at one of the driver ribbon cables and it looks like there might be shorting damage, but I do not have a good way to check this. It does not seem like manipulating any ribbon cable has any effect one way or another. Is there anything else I can try or is this just a dead panel that is not worth any more effort?

The first picture shows the overall picture problem. Disconnecting the FFC between the outer and inner edge will make the outside go white (like a normal disconnected tcon), but nothing can make it go normal. Second picture is the unknown marks on the driver ribbon. Third picture is a "good" driver ribbon. The remaining pictures are all different angles of the potentially burnt driver ribbon.