Sharp Aquos lc-70le857u 70" TV display problem

[egreene15]

Hey everone, i'm new here and have spent a few days searching threads for my symptoms but haven't found anything...I'll quickly describe and see if any of you can help.

My in-laws tv stopped working a few months ago, threw the 2-5 blinking code and wouldn't turn on. Being out of warranty, barely, and not wanting to spend more money on it (was already replaced one), they put it aside, unplugged. Fast forward a few months to earlier this week...I plugged it in and there was no error code! However the display was clearly not working correctly, no A/V sources are connected to the tv, on power up i never saw the SHARP logo screen or anything for that matter, i hit the menu button on the remote and could see the menu titles but they weren't normal colors and they appeared on the screen slowly (took about 30 seconds for the image to get full bright) If i tried to scroll it would again take 30 seconds for the screen to show any response.

I have talked to SHARP and done a hard reset, they said i would have to have it "serviced". Picture below is what it currently looks like when i turn it on, the longer i leave it on the brighter the image gets, all the way to the point where the entire screen is bright yellow/white. I have checked and get 12vdc to the Tcon board, no physical damage to the screen either.

When i go into the service menu during the hard reset i get almost a perfect picture and brightness...

Send me any thoughts!

[ReeceyBurger123]

Re: Sharp Aquos lc-70le857u 70" TV display problem

Sounds like Mainboard failure to me.

[ReeceyBurger123]

Re: Sharp Aquos lc-70le857u 70" TV display problem

Try possibly heating the Mainboard with hair drier to see if it clears up the issue.

[budwich]

Re: Sharp Aquos lc-70le857u 70" TV display problem

its appears to be the "standard" bad tab issue. You can search thru here using either "sharp 70" or "vizio 70"... there are lots of threads in and around this problem. The set can't be fixed because the tabs are not replaceable BUT it can be "saved" by removing the defective one (s) on one side or the other.... but you only get one chance to make a choice so proceed with care.

this is my "story" https://www.badcaps.net/forum/showth...light=sharp+70

[egreene15]

Re: Sharp Aquos lc-70le857u 70" TV display problem

its appears to be the "standard" bad tab issue. You can search thru here... there are lots of threads in and around this problem.

Read a little about it I think when I was thumbing around here, if I remember correctly there is no easy solution of just replacing a board is there?

[budwich]

Re: Sharp Aquos lc-70le857u 70" TV display problem

Yep.... lots of successful "saves" so it can be done. People will help so go slow, make sure you understand what's happening and where. By removing cables (unclampable one), you can eliminate which side is bad. That's the process.

Of course, the task is somewhat difficult because of the size of the set, and the amount of space you need to work on it.... but slow and sure will get you there.

[egreene15]

Re: Sharp Aquos lc-70le857u 70" TV display problem

Try possibly heating the Mainboard with hair drier to see if it clears up the issue.

Tried that and no change...thanks for the idea!

[budwich]

Re: Sharp Aquos lc-70le857u 70" TV display problem

:-)

[egreene15]

Re: Sharp Aquos lc-70le857u 70" TV display problem

Yep.... lots of successful "saves" so it can be done. People will help so go slow, make sure you understand what's happening and where. By removing cables (unclampable one), you can eliminate which side is bad. That's the process.

Of course, the task is somewhat difficult because of the size of the set, and the amount of space you need to work on it.... but slow and sure will get you there.

Thanks! I went thru your thread earlier and don't think I have a bad side, no issues when connecting or disconnecting my tcon ribbons

[budwich]

Re: Sharp Aquos lc-70le857u 70" TV display problem

actually you need to disconnect the "corner cables" to eliminate the possible "tab problem". In my case, the tab driver was causing enough issue for the code flash but there were time when it was OK so it depends on how "bad" the tab might be. Anyways, good luck in your "quest".

[freakaftr8]

Re: Sharp Aquos lc-70le857u 70" TV display problem

This looks like a bad tcon board. Especially since it appears that the screen is holding images. Like image retention. Mostly a problem with the gamma processor on the tcon. Locate the ic labeled Maxim. Are you getting a steady 2.2v to it? This board would also hold the responsibility of originally throwing the 2-5 error.

[egreene15]

Re: Sharp Aquos lc-70le857u 70" TV display problem

This looks like a bad tcon board. Especially since it appears that the screen is holding images. Like image retention. Mostly a problem with the gamma processor on the tcon. Locate the ic labeled Maxim. Are you getting a steady 2.2v to it? This board would also hold the responsibility of originally throwing the 2-5 error.

I took off the tcon board and looked on both sides for an IC labeled Maxim but couldn't find anything. Here is a picture if that helps you guide me...

I've been thinking its a tcon issue all along but not sure how to test it...thinking about just ordering a new board and testing it by pure replacement. Happy Thanksgiving everyone!

[freakaftr8]

Re: Sharp Aquos lc-70le857u 70" TV display problem

I'm thinking of.IC6801

[egreene15]

Re: Sharp Aquos lc-70le857u 70" TV display problem

Thanks for the help freakaftr8! Any good references on how to check voltage on an IC?

[freakaftr8]

Re: Sharp Aquos lc-70le857u 70" TV display problem

On those im not too sure. But the voltages on a normal as15 should range from 0 to 12v on each pin incrementally increasing on each pin.

[egreene15]

Re: Sharp Aquos lc-70le857u 70" TV display problem

Well I swapped out the T-Con board to no avail, still same issues. I've got a power supply board on the way and I'm going to try that. I did a hard reset after I swapped the tcon board, does anyone know if I need to do anything else after swapping a board that could maybe reset things? Thanks for your help!

[budwich]

Re: Sharp Aquos lc-70le857u 70" TV display problem

I think you have nothing to lose by disconnecting the corner interconnecting cables (one on each side, one at a time) and see if it changes anything.

[freakaftr8]

Re: Sharp Aquos lc-70le857u 70" TV display problem

Wow im surprised ghe tcon didnt fix it. Power supply is most likely ok. Id say panel issue now. Try disconnecting one side at a time on the panel to tcon and see if picture stays the same on either side.

[egreene15]

Re: Sharp Aquos lc-70le857u 70" TV display problem

So power supply board is ok, swapped it out and no change as predicted. I unhooked the right corner(looking at the back) interconnecting cable and the opposite side screen(right side, looking at the screen side) looks perfect. I unhooked both back corner cables and got a bright white screen with flickering lines all over. I unhooked just the back left cable and screen pretty much stayed the same as if i hadn't unhooked anything. Thoughts?

[budwich]

Re: Sharp Aquos lc-70le857u 70" TV display problem

You are there... :-) Not sure about your "right and lefts"... but it doesn't matter. The side that you connected back up and got nothing (same of all unhooked), that's the side that is BAD..... because the set was trying to work running with that BAD connection and it obviously can't. So go slow still. Go back to the "good screen mode" and take a picture and post (use some good video input from a test dvd or something people will know exactly what you are seeing will help significantly). Without this, you may be still looking at multiple tab problems... only a good picture of a good test screen will help confirm things.