Sharp LC60LE660U screen flashes on power on then nothing

[rddube]

Hello to this wonderful community.

I thought I would start a new thread for this TV I bought from someone who said that it just would not turn on any more.

It's a Sharp LC60LE660U and when I tried it it just flashed the backlights very quick and then the standby light would stay on white, nothing else. I can then turn off the tv. There is no image, no sound.

I stumbled across this thread about leds maybe being an issue, so I disassembled it and checked every lead (they are Samsung 7030 leds 6V and they all tested fine.

So now I don't know what to look for, can anybody help? Sam_sam_sam started helping me in another thread, but I now started this one in the right forum. Thank you to everyone!

[sam_sam_sam]

Re: Sharp LC60LE660U screen flashes on power on then nothing

Please repeat how you get the Back light to come on which board did you disconnect
Show which board it is

[rddube]

Re: Sharp LC60LE660U screen flashes on power on then nothing

It is this board, the Tcon.

[budm]

Re: Sharp LC60LE660U screen flashes on power on then nothing

When you disconnect the PL connector (it looks to be for supplying the 12VDC to run the T-CON) on the T-con side or on the power supply side, what Voltages do you have on the pins of the connector that you removed?
No error codes?

[rddube]

Re: Sharp LC60LE660U screen flashes on power on then nothing

Hey Budm, thanks for your intervention! That monitor you helped me fix (Viewsonic) is working like a charm.

I am at work right now, so will get to your question about the voltage on the PL connector later tonight. No, I get no error codes, just a quick flash of the backlights and then the TV stays on with the standby led lit up white.....I can then turn off the TV.

Will get back to you later!

[Nick's Tvs]

Re: Sharp LC60LE660U screen flashes on power on then nothing

Very common issue with these, you have a main board failure. You will not be able to fix it yourself you will have to purchase a brand new board.

A lot of places are out of stock for these guys but if you go to eBay and buy there, they have a few for sale.
Here is a link to the cheapest one out there for your model:

https://www.ebay.com/itm/Sharp-Aquos...LH_TitleDesc=0

It does come with a 30 day warranty.
They go fast, so I wouldn't wait to long before getting it.

Good luck

[rddube]

Re: Sharp LC60LE660U screen flashes on power on then nothing

Budm: Ok, when I disconnect the PL connector from the Tcon, I get 11,75V on pin 1 and 2 and 0V on pin 3 and 4. I get no error messages. I did a test and disconnected the left ribbon cable from the TCon (picture attached), everything else connected and the TV powered up with the right side working but the left side all white. I could get into the menu. When I reconnected the left ribbon cable, same symptoms as from the start i.e. the screen blinks very fast and the led light is on solid color white.

Nick: Thanks for the heads up, but I think I will try and repair it with Budm in the picture, I wouldn't be surprised that he finds the fault even if it's on the main board. I'm suspecting its not the main board, because of the test I did...but maybe it is. Do you know what fails on the main board?

[budm]

Re: Sharp LC60LE660U screen flashes on power on then nothing

Right now it looks like panel problem because you can get half of the screen to work, it may have bad side tab driver problem.

[rddube]

Re: Sharp LC60LE660U screen flashes on power on then nothing

Hi Budm,

Ok, I think you are right. I tried it with the right ribbon cable disconnected from the Tcon, and I get backlights but for about 1 second then blank. I retried with left ribbon cable disconnected (right cable connected) and TV stays on and works, but half the screen.

So if it is the little panel at the bottom of the screen, what should I be looking for? I notice there are a number of smd caps and resistors and what seems to be test points. Do you want me to take close up photos of that whole little board (probably 2 or 3 photos side to side) or what should I do? Tks Budm.

[budwich]

Re: Sharp LC60LE660U screen flashes on power on then nothing

besides the edge boards at the bottom, post a picture of your "half working display"... make sure you input something that provides some "known picture" (ie test pattern) so we can look at the results... they might indicate where to go from there.

[rddube]

Re: Sharp LC60LE660U screen flashes on power on then nothing

Ok, I took some photos of the edge board, bear with me if they are not that great it is quite a long board and trying to hold my light with the camera in the other hand, well...but please shout if you want me to focus on something specific.

As for the picture of the TV with the left ribbon cable disconnected, well this is almost a circus act. I popped up the menu, but since the tv is lying on it's face, I had to lift it and try and take photos so I guess I'm an acrobat now. The menu is at the bottom of the photos, upside down because I have the TV bottom side facing me.

But feel free to let me know anything you need and I will do my best to respond. Thanks Budwich and Budm!

Oh, by the way did you notice the length of thos ribbon cables, for some reason they are way to long so they have folded them - could that be a possible cause, a kink or broken line in the left cable? I guess I could always switch them around and see what that gives, but I'll wait for your advice before fiddling around with that.

[rddube]

Re: Sharp LC60LE660U screen flashes on power on then nothing

Gentlemen, when you look at photo 4, you can see that the left edge board is made up of 2 boards connected with another ribbon cable. That means there are 4 edge boards, 2 on each side connected with a ribbon cable between each other. When I disconnected the left half (so I had everything connected except that half panel board at the left, then I had the TV turn on and i then had 3/4 of a screen which seemed to work perfectly. There is the bottom menu backwards, but I also see a horizontal line at the top that you can see in the 8th photo (which might be another problem?).

So it seems that the problem is coming from that half panel board which is totally on the left of the photo #4 (since we are looking at the back, that would be the half panel board on the right bottom of the tv. Hope this helps?

[budm]

Re: Sharp LC60LE660U screen flashes on power on then nothing

Start checking the resistance of those small light brown color rectangular caps on the the board that you left disconnected, hopefully it will be just bad cap with low resistance reading.

[rddube]

Re: Sharp LC60LE660U screen flashes on power on then nothing

Ok Budm, I checked them all and they all but 1 look ok greater than 235K. One of them, when I would put my needle test leads on the solder joints, I would get megahoms, but when I would put it on the edge of the cap it was 243K ohms. I had to jiggle a bit my leads to in the solder joint to finally get it to read 243k ohms. Could it be a bad solder joint? How can I tell, as I tried from the one of the edges of the cap to where is was connected to the edge of the cables going into the panel, that was ok. The other side, I don't have a test point that I could measure the edge of the cap to.

Do you want me to try and get a macro photo of the soldering of a few caps on that board including the suspect one? Tks.

[budm]

Re: Sharp LC60LE660U screen flashes on power on then nothing

I am looking for something with 100 Ohms or less for the bad caps.

[rddube]

Re: Sharp LC60LE660U screen flashes on power on then nothing

I rechecked the caps (twice) to make sure I hadn't missed one. Most of them are in the k ohms area, while a few 3-4 are in the ohms area the lowest one being at 435 ohms. I checked on the good side of the panel boards and I get similar readings i.e. most in the k ohms area while a few in the 440 - 450 ohm area.

I also checked the resistors, they all give a reading some of them just a few ohms which is probably ok.

So I guess that means bad news? Tks Budm.

[budwich]

Re: Sharp LC60LE660U screen flashes on power on then nothing

the good news is that you isolated your focus to a part of the edge board and that you got "3/4s" of a screen. That means that the tcon to panel connections are good. The bad news is that it is likely a issue from the bottom edge board (end "piece") to the panel and the side tab drivers. You might get lucky with your checks of the smd components on the edge board in question... but because of the horizontal line, it is also likely that the problem is with the side tab drivers. You need to look at these especially the one in the bottom corner of the side. You need to inspect all of them for heating / damage... this has to be done from the front... you need to take off the bezel to see them. Anyways, if I am right, the set can still be save once you have done your checks. The "save" is done by removing all of the side tabs on that side of the panel. Lots of threads in the forum about this "save". The tv will basically operate "fully normally" along with a good picture.

[rddube]

Re: Sharp LC60LE660U screen flashes on power on then nothing

Budwich, with your input and that of Budm, I think we are getting closer. When I first thought that it was a led problem I opened her up to get to the leads and had noticed one of those side tabs being a little crimpled, but didn't pay too much attention to it my main focus was to diagnose the leds.

When I found out the leds were good, I put her back together and sort of placed that "crumpled" tab the best I could not thinking the problem could come from there.

So this morning, I reopened removing the metal frame. That crumpled tab seemed to be a lot better than when I first encountered it but it was now in free air so I thought I'd do my tests touching it to see if it changed anything. Note that the crumpled tab is the bottom one on the right, closest to the where are the panel boards.

So attached are photos of my results with my findings.

Photo 1 shows the screen now with the left ribbon cable to tcon disconnected (looking from the back of the TV, but from the front it is the right side cable) This is the cable that I disconnected last night and would get half a picture and when I disconnected the second half of that side it got 3/4 piciture. Funny, I get no picture like I did when it was facing down instead of up?

When I touch the crumpled tab lightly putting some pressure, nothing happens. So I decided to touch the left bottom tab, and wow it was hot, burning hot. But as I touched it, something started moving on the screen as if more pixels were being shown. So I turned everything off not to damage any further and took more photos. Photo 2 is the left bottom tab that becomes hot - looks very good physically. Photo 3 is photo of crumbled tab bottom right. Photo 4 is a photo of middle right tab that looks normal and doesn't become hot, neither of the other tabs that I checked on the TV.

So you are saying that this can be repaired in some way? Which one is the culprit, is it the crumbled one (I guess so, but why is it the opposite one that becomes so hot?).

Anyway you got me excited now. Oh, and for Budm, I rechecked those caps again and they all seem ok.

[budwich]

Re: Sharp LC60LE660U screen flashes on power on then nothing

well, all I can say is don't run the set very much in this mode as you may very well burn out your "last hope". I post this quickly. Hopefully, you get the warning sooner than later.

[budwich]

Re: Sharp LC60LE660U screen flashes on power on then nothing

now for the longer explanation.
the side tabs are driven in "pairs" so to speak both helping to power the signal across the panel in a fashion. However, the set can operate with only one side of tabs but the result will be a "slightly out of design spec" or "compromised" operation but for normal viewing will likely be OK unless you have "golden eyes". :-)

Anyways, when one side tab is not functioning properly, it puts an additional load on the other one which is now trying to drive the panel and the "not so good" other side tab. I think that is the "hot" problem that you are feeling on the "GOOD" tab. As you can probably see, I am kind of telling which is good and bad.

As you have found, when disconnected certain cables you got a "picture" one way and not the other. This is because when you disconnected the "bad" tab from being driven by the bottom edge boards, the system was able to make a picture with the remaining hardware. When you change this and disconnected the "good" tab(s) (ie. opposite side), the system had to try to operate with the bad tab(s) in place and failed, thus shutting down.

Hope you can follow the reasoning. My guess is that the bad tab is the crumpled one and its loading down the other one causing it to potentially over heat.... DON'T let that happen because once the other side dies, your set can no longer be saved... the panel is garbage but the cards can be salvaged for sale if you want.

Read some threads in and around these sets and you will get a better idea / understanding of what's up.

The "save operation" is the removal of all the tabs along the side that is bad. NOTE this is a one time operation and CAN NOT be undone so read and make sure this is your only way out. FURTHER, DO NOT touch / play with any of the tabs along the bottom edge boards as when these are damaged they are NOT duplicated and the set can not work with them damaged / removed.

Again, read and read a few threads in this domain.... this set is likely "saveable".