Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

[Scollins]

Hey all,

This is a rescue TV that I received and revived back to life a few months ago. Now it's trying to die again and it's hard to go from a 60" to a 32" monitor so I want to save it if I can because I really don't have the money to shell out to buy a new one.

I originally thought this was the same error that I was getting last time, something about the panel faulting out. It turns out that by going into service mode, the panel isn't faulting, but the monitor is. It states Monitor Error 6, but on page 30 or 5-5 of the repair manual, it doesn't describe any monitor error causes.

For diagnosis, I attempted to go into the service menu and reset all of the warnings but it doesn't seem to help. When I had a cold start the monitor came right on, but now it only flickers. It's super freaking hot here in FL right now so could this be a heat-related thing? Both lights stay on and nothing clicks, just a black screen and two green lights. I also removed the back and nothing appeared popped or messed up. I took a picture, but it's the same as the old one so if you guys need it I can post it.

If anyone has any suggestions I'd love to them. I also have flickering that occurs which can get annoying, but I can deal with if I can see what's on the screen.

Thanks,
Sam

[nomoresonys]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

Can you see anything on screen with a flashlight when you hit menu or anything?

[Scollins]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

So this morning just for fun I tried to turn it on and it stayed on. I went through the process of resetting all of the settings to see if I had messed up anything.

One restart and it was good, the image came back but the backlighting was flickering something awful. (I've dealt with the flicker but not like this. And to clarify what I mean by flicker. The image doesn't flicker, but it looks like the backlights do. When they do it is in bands of light across the entire screen, typically brighter than what is normally on the screen)

The power saving leafs kept showing up on the bottom so I went into settings and turned that off. The flickering significantly reduced and seemed to stabilize for a bit. What board controls the OPC and power saving features? Could that be going bad?

My finance just texted me telling me the Xbox that we use as a home system controller went to sleep and turned the tv off with it. When she turned it back on the image was there, just very dim like the backlight was off again. So, it looks like the panel is working correctly, just something controlling the backlights and them being on. The power saving feature affecting the flickering makes me wonder if that module is crapping out on me.

[nomoresonys]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

If all those features are off and it still flickers, sometimes it's a faulty backlight or loose connection etc.
in the backlight circuit.

[Scollins]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

So here's an update. It appears to work when it is cool, but after an extended time shuts off so I think it might be related to the temperature (ranging from 70-80) and the connection as it appears to work first thing in the morning but not later.

I will try to take the back off and start by looking at the tcon board to see if the flicker occurs from that or not. What specifically should I look at for a loose connection?

Edit after reading my last comment: Also just to clarify, the image doesn't flicker when the backlight is not working. The image is steady light or no light, it's the backlight that flickers and only does so when it is on.

[nomoresonys]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

Turn down the BACKLIGHTS not brightness if possible, see if it stays on longer before faulting.

[Scollins]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

Okay, will that be in the menu or service menu?

[nomoresonys]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

Quite often it's in the regular menu but sometimes you have to go in service menu, if you go in service menu be very careful what you change in there, maybe make note of any changes you make so you can put them back if needed.

[nomoresonys]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

Yours is in the onscreen display menu-picture-, both backlights and brightness adjustments are there, no need to go into service menu to adjust backlights.

[Scollins]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

Interesting update. The flashing gets far far worse when the backlight is low, and goes away completely when the backlight is higher. I feel like whatever board controls that might be the guilty party here. Or is that the actual ccfl backlights starting to die on me? I don’t mind keeping it brighter if that’s what i have to do to keep it on.

[nomoresonys]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

Ok, for a minute there I was thinking you had led backlighting, we better start with:
Test connector from mainboard to powerboard on powerboard side with all boards hooked up, test with tv plugged in but off then hit power, report both conditions here, give pin number, pin description/name and condition both off and when you hit power on. That's if you want to use a multimeter, setting at 20 VDC, positive lead on pin and negative lead on chassis ground/metal back of tv for those measurements. Example by shopjimmy in second link in my signature below.

[Scollins]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

I'll have to get a multimeter to test this as I don't have one that works anymore. I'll try to go through the manual and find which connectors you are referring to, but if not can I post a picture of the board for you to help me figure out which ones I need to measure?

[nomoresonys]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

For sure, we love those pics. the more the better, even the cheap meters are ok for most stuff, big box stores got em for about 7 bucks on up.

[diif]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

Sounds very much like you have a failing ccfl tube, especially the bit with turning the brightness down causes it to flicker more.

[Scollins]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

If I have a failing ccfl tube is that worth replacing to keep the set or would it be time to start saving for a replacement.

[nomoresonys]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

I'd say yes, 60 is a decent size, replacing a ccfl isn't much different than replacing leds, main thing is to take it slow and BE VERY CAREFUL not to break the panel, those harbor freight suction cups are good tools for the job and youtube videos of successful repairs.

[nomoresonys]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

Here's one with a "led upgrade": https://www.youtube.com/watch?v=jdk-GxU7TU4

[nomoresonys]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

Working on a sharp 37 inch: https://www.youtube.com/watch?v=8CCPLZNt2z4

[Davi.p]

Re: Sharp LC-60E77UN: Backlight comes on then flashes blue and dies

OK lets we see if i have understood all your sentences, if sometimes some horiz.bars are brighter than normal image maybe something is wrong with the balancer board if it's present, so maybe it's better to exclude the BL protection and feel the heat on each balancer's transformer. Maybe some other component on that board can be failed, and check for dry joints there and hit with a handle in all points searching for bad contact, check also, if present, tube's sockets and burning traces..