Sharp LC-80LE661U - Power's off after 4 seconds.

[Donmessi]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

Where you able to fix the problem on your tv?

[jackf-nc]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

Any updates on this? I am having EXACT same issues. Have replaced main board with same results (sharp logo and then off) after 4-5 secs.

[nomoresonys]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

Guess youy could try a tcon, one there for 32 bucks has a make offer option too. https://www.ebay.com/itm/SHARP-LC-80...-/371882999505

[nomoresonys]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

.

[nomoresonys]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

"Not sure exactly what you mean here. I tried using a 2k resistor (only thing I had on hand) between the ps-on and ground, then also between pnl_pow and ground, hoping it would turn on the LCD but didn't get any results" NO you don't use the ground, you use the 5 volt, you need to jump 5 volt with ps-on and pnl-pow. to see a display NOT ether or, you DO NOT use ground, afaik.

[budwich]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

So you need to trace that error pin to see where it goes... I am assuming it comes from the tcon.... but you can confirm that. IF so, that would likely mean that the tcon is shutting the system down maybe.

[overlyAmbitiousSloth]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

Make sure you are identifying your pins correctly, you should have around 0 volts on the ground pins.

Double checked and am definitely getting 4.5 - 4.8v on the ground pins when the TV is on (only for a few seconds until it shuts off, then it drops down to 0v).

I believe you can use a 1k resistor and connect 5 volt stby with ps-on and panel 12v, maybe one of the super techs here can confirm procedure.

Not sure exactly what you mean here. I tried using a 2k resistor (only thing I had on hand) between the ps-on and ground, then also between pnl_pow and ground, hoping it would turn on the LCD but didn't get any results.

One other note: there is a couple other threads dealing with 80 in panels that you should read... they might provide some further information.

Did some digging and I saw some power board and backlight issues, and some issues that registered an error code, but I haven't spotted anything similar just yet. I'll do some more perusing to see if I missed anything.

Your problem seems similar to this one right below. https://www.badcaps.net/forum/showthread.php?t=63849

I so wish this was my problem. Sounds like these guys are getting stuck in a reboot loop. Mine powers up, stays on a few seconds and then shuts down completely. Tried it anyway with both a 2Gb and a 32Gb (didn't have any 1Gb USBs hanging around) and there was no change in behavior. Seems like it didn't even register it was plugged in and shut off as usual.

you night try monitoring the ERROR pin / connection at power plug in, power on, and at shut down to see if thats the "flag" for shutdown... probably... maybe.

Tried this and it does seem to be spiking in voltage after the screen blips out. While the screen is on (first 4 seconds) it is at 1.4v then bumps up to 2.5v after the screen shuts off, it stays at 2.5v for a few seconds until I hear a click from the power supply and then drops to 0v.

[budwich]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

I see the following labels on the pin label for the cable between the mainboard and the powerboard:

PNL12V
GND
UR13.2V
UR13.2V
GND
GND
PS_ON
PNL_POW
NC
NC
ERROR
STB

Would it be the PNL_POW pin that I need to short to ground?

When taking power readings earlier I saw 5V on that pin. What type of resister would I need to use? Or, could I short it directly to one of the GND pins above (was seeing 4.5V on the two ground pins 5th and 6th from the top)?

you night try monitoring the ERROR pin / connection at power plug in, power on, and at shut down to see if thats the "flag" for shutdown... probably... maybe.

[nomoresonys]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

Your problem seems similar to this one right below. https://www.badcaps.net/forum/showthread.php?t=63849

[nomoresonys]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

You can download firmware on this page, guess you put the usb with the update in then plug in tv, should update by itself. It won't fix it if firmware isn't the problem but it won't hurt any. https://siica.sharpusa.com/product-downloads

[budwich]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

:-( it appears that the structural design of the 80 is different from the 70 which has a plastic "plate" covering the lower edge boards. I am not sure that it is worthwhile doing further disassembly at this time. It is disappointing that the shutdown does provide some form of "code flashing" or otherwise to indicate some sort of error code. Your tests that the system does detect a totally disconnected tcon from the MB indicates that the system is somewhat functional and that some other fault is causing the shutdown.

One note on disassembly beyond this point, I used blocks of wood strategically placed on the various points of the "metal back plane" to set the panel on so that I could leave everything connected and still get access to screws / hardware to remove the front bezel which then gives you access to edge boards / tabs that connect to the panel.

One other note: there is a couple other threads dealing with 80 in panels that you should read... they might provide some further information.

[overlyAmbitiousSloth]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

hmmm the fact that you can't connect with any external inputs doesn't sound good and points towards the amin board which houses those (I think). further, you still need to try to disconnect the small corner cables that interconnect the bottom and side edge boards... this may give you a better understand of what it happening.

I may be missing something, but I've taken off the speaker mounts and bezel and am not seeing cables in the corners. The only cables I see are a couple pair of ribbon cables at the bottom of the TV. I've attached a couple pictures to give an idea of what I'm seeing. Unfortunately, I can't get the ribbon cables undone without completely disassembling the LCD housing. It looks like it would have to be loosened on all sides and then lifted up, probably just a a half inch, to disconnect those ribbon cables. Before I dive down that rabbit hole, do these look like the right cables?

[budwich]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

hmmm the fact that you can't connect with any external inputs doesn't sound good and points towards the amin board which houses those (I think). further, you still need to try to disconnect the small corner cables that interconnect the bottom and side edge boards... this may give you a better understand of what it happening.

[overlyAmbitiousSloth]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

multitudes of dvds (thx ones and others) have special features for tv setup / colors etc. In addition, there are computer files that provide various test patterns.

Since the system still shuts down, regardless of the tcon connections, that would imply a problem back from there. However, it may depend on why the shutdown.... voltages out of range? main board issues?

The corner cable test that I suggest is potentially still valuable depending on what happens. Still concerned about the lack of uniform white on the disconnected side.

Well, I disconnected the t-con ribbon cables again (one at a time) and there is definitely not a uniform white displayed. In fact, it seems a heck of a lot worse than it did last night. I may have screwed something up in the mean time. I did have the power cable plugged into a six-strip and only powered off the strip between plugging and unplugging cables instead of fully disconnecting the power. Aside from that I can't think of anything else I did that would have effected it.


Oh, and I can't get any external inputs to display. TV powers up, shows Sharp logo and then shuts off in a few seconds. I've tried multiple inputs and haven't seen anything displayed (don't see menu's either and can't get the service menu to pop up with button combinations). So that puts in me a tight spot with getting test patterns to display.


Anyway, I've got some pictures attached.

Does this look like a panel issue? If that's the case, do these type of tv's have backlight LEDs that could be replace? Or does it just mean the panel is shot?

Thanks for the help and advice.

[budwich]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

multitudes of dvds (thx ones and others) have special features for tv setup / colors etc. In addition, there are computer files that provide various test patterns.

Since the system still shuts down, regardless of the tcon connections, that would imply a problem back from there. However, it may depend on why the shutdown.... voltages out of range? main board issues?

The corner cable test that I suggest is potentially still valuable depending on what happens. Still concerned about the lack of uniform white on the disconnected side.

[overlyAmbitiousSloth]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

as you can see from your pictures, the "issue" seems to be on the left side... when that side is disconnected.... while opposite "test" appears quite a bit better in terms of "uniform white". My concern would be that perhaps it is a "marginal panel issue". It would help if you feed in a known test pattern (color bars) which will potentially highly issues better. Further, you indicate at the start, that the set shuts down after 4 seconds. does it still do this with either side of the tcon disconnected? IF not, then that would point to a panel issue.... but if so, then it might indicate a problem away from the panel and more dealing with controls / boards.

One other point.... I know the panel is huge (previously I work with a 70in that was tough)... so be careful. There are small white cables in the bottom corner of the panel on each side. These cables interconnect the bottom edge boards to side edge boards. If you are careful, you can disconnect those cables... again one at a time and see the result.... keep all other cabling connected. You should see a full picture with some darkness... again use a test pattern (color bars) and perhaps your display will show you something.

Yep, it does still shut off after 4 seconds regardless of which of the t-con ribbon cables I had unplugged.

I've been doing some reading on feeding the t-con board a test pattern and am not finding any instructions on this type(G477FM05). I see some other boards have pins that can be jumped or shorted but I don't see anything on this board that screams 'bridge me' (I also don't really have a clue what I'm looking for, just comparing to the pictures in this post https://www.badcaps.net/forum/showthread.php?t=26790 ). I've attached a picture of the board for reference (can take better pictures later if it helps).

Any idea's on how I can get it to display a pattern?

When I get home I'll check for those cables running the bottom corner/edge of the LCD and see if disconnecting those shows new results.



PS - Found documentation on the RS232 port that I asked about earlier in the Operation Manual for the LC-80LE661U. Looks like its designed for remote control of the TV. No help in this scenario but kind of a cool option to have.

[budwich]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

as you can see from your pictures, the "issue" seems to be on the left side... when that side is disconnected.... while opposite "test" appears quite a bit better in terms of "uniform white". My concern would be that perhaps it is a "marginal panel issue". It would help if you feed in a known test pattern (color bars) which will potentially highly issues better. Further, you indicate at the start, that the set shuts down after 4 seconds. does it still do this with either side of the tcon disconnected? IF not, then that would point to a panel issue.... but if so, then it might indicate a problem away from the panel and more dealing with controls / boards.

One other point.... I know the panel is huge (previously I work with a 70in that was tough)... so be careful. There are small white cables in the bottom corner of the panel on each side. These cables interconnect the bottom edge boards to side edge boards. If you are careful, you can disconnect those cables... again one at a time and see the result.... keep all other cabling connected. You should see a full picture with some darkness... again use a test pattern (color bars) and perhaps your display will show you something.

[overlyAmbitiousSloth]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

Make sure you are identifying your pins correctly, you should have around 0 volts on the ground pins.

Thanks for the heads up. I'll double check to make sure I'm reading the proper pins when I get home this evening.

I believe you can use a 1k resistor and connect 5 volt stby with ps-on and panel 12v, maybe one of the super techs here can confirm procedure.

I can give it a shot, doesn't sound too complicated. Out of curiosity, is there any sort of guide hanging around for this (I've run through some of the guides on here and they're great, just haven't seen anything on this).

so... the pictures that you posted seem to show some "issue" with the display.... perhaps although it could be the "photography". The "white" side that indicates the side of the tcon that is disconnected should be uniformly white. One picture appears to show some horizontal "banding" of darkness. Was this actually there or just a "poor photo" not really representative of the image that was there?

I've got a couple more pictures attached. Some of them show this banding effect, some of them don't. I don't have the TV base/stand so I was kinda holding the tv up with one hand, camera with the other and flipping the power strip on and off with my foot... so the pictures are definitely janky. I'll go through the same process this evening and see if it was just weird angles.

Would that point towards a poor LCD?

[budwich]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

so... the pictures that you posted seem to show some "issue" with the display.... perhaps although it could be the "photography". The "white" side that indicates the side of the tcon that is disconnected should be uniformly white. One picture appears to show some horizontal "banding" of darkness. Was this actually there or just a "poor photo" not really representative of the image that was there?

[nomoresonys]

Re: Sharp LC-80LE661U - Power's off after 4 seconds.

I believe you can use a 1k resistor and connect 5 volt stby with ps-on and panel 12v, maybe one of the super techs here can confirm procedure.