Bad driver(s)? Sharp LED TV

[scuby]

Re: Bad driver(s)? Sharp LED TV

sorry I missed this post... :-(

That is the right kind of test with the tcon but it gets you nothing? That usually points to a problem with getting some signal into the panel as the black side should see something.

That could either mean it isn't being sent or it can't make thru to the panel.
You are likely going to have to check some voltage points which should be printed / labelled on the tcon and / or the bottom edge boards... things like "V..." (eg. VCOM and such). These might highlight the issue. Since you have tried two cards, then if there is a voltage problem, it is likely at the panel / edge boards. IF things look OK, then I would say, the main board is an issue. More likely since you never see any flash codes.

No that test gets me nothing. I posted some pictures. I get one half white, the other half remains black and imageless.

Excellent post if not simply due to being informative and arming me with new things to try. I hate not understanding things. I have a hard time letting it go in that case.

So I think by reading your last post you read mine some more and got some answers however:

I will check the Tcon tomorrow am (1am here in europe now). If/when I find values I'll measure them and report back.

Good catch on the significance of the dimming, my other Sharp TV does the same. Hadn't made the connection. On that note it seems indeed to be completely missing a video signal at times and sometimes (with the blue, getting a small scrambled amoutn through the LVDS). Also what the Tcon test showed. Not a single pixel gives me image of any kind. No menu, nothing. No codes and the backlights always fire up just fine.

So I'll report back after testing the Tcon voltages if I can find them.

So it is possible that even though there is sound the video processing part of the Main Board is busted?

I would be happier than might seems reasonable to get this thing going

I'll also inspect the side tabs for heat etc. All the other boards and connections are clean, very little to no dust and no signs of any damage or heat in the set at all. Every capacitors looks healthy etc. Visually the set is very clean. It's about 4 years old and saw very little use I was told.

thanks

EDIT: with all cabling plugged in no codes, it turns on the backlight will auto detect a signal and I can hear audio. Sometimes it will show the blue screen sometimes the screen is completely blank (see pics on previous post). No menu nothing. It has played like that for an hour or more just to test heat getting into the components. Only change seems to be the longer it's on the less likely the "blue portion" of the screen tends to light up at all.

[budwich]

Re: Bad driver(s)? Sharp LED TV

allright: here's wat I've done:

I have 4 cable/ribbons running from the Tcon to the panel. My backlights always come on every time I power up the set. I have no codes flashing at any time.

I have a source playing verified by it's audio.

Unplug the right most cable/ribbon: corresponding half of screen lights up mostly white/grey but lot's of colored lines. See Pic 1

Unplug the second cable from right: corresponding half of screen goes completely white. See Pic 3

Same is true of the left. 1 cable results in a more colorful lighting up of the screen. Disconnect both it's all white. See pic 2, it goes fully white like pic 3 on the other side too.

Disconnect all four and the set switches off.

What can we conclude from this?

sorry I missed this post... :-(

That is the right kind of test with the tcon but it gets you nothing? That usually points to a problem with getting some signal into the panel as the black side should see something.

That could either mean it isn't being sent or it can't make thru to the panel.
You are likely going to have to check some voltage points which should be printed / labelled on the tcon and / or the bottom edge boards... things like "V..." (eg. VCOM and such). These might highlight the issue. Since you have tried two cards, then if there is a voltage problem, it is likely at the panel / edge boards. IF things look OK, then I would say, the main board is an issue. More likely since you never see any flash codes.

[budwich]

Re: Bad driver(s)? Sharp LED TV

sorry... I wasn't trying to "cast" any "despair" towards anyone... just trying to understand where things are at exactly... plus my reading ain't so good ... :-)

So a couple of things... first when you have all cabling plugged in, does the set display anything and stay displaying... no flash codes?

Next... have you looked at the side tabs of the set if visually you can see any sign of heating / "abnormal" when compared to others?

Next, beside the tcon to panel cabling, there are a couple of "points" where "flex cabling / ribbons" can be disconnected / unclamped? These provide ways of isolate the panel "sections" so that if there is a panel issue, potentially, it can be isolated away while the rest of the panel still work "almost". At the bottom corner, on each side there is a small ribbon cable which connects the bottom edge boards to side boards. You can unclamp one end of this cable and power up the set to see what the result is. You can do the same with the opposite side. This test allows the tcon to still fully drive the panel because all of its cabling is intact but "isolates" the side drivers IF they are bad and causing issues. Depending on the results, there are some other points that also help isolate things. Post any results and go from there. I am leaning towards a problem with bottom edge boards (some smd component) but have seen issues / posts where a side driver did some "bad stuff" to the overall display.

One other point... this.... "PS: with one side disconnected from the Tcon the white side will dimm after a few seconds as if saving power. Hitting the menu button or volume will trigger the screen to illuminate fully again. It seems to respond that much at least. It also does this when displaying the blue screen which varies in size when turned off and on again but is always on the same side." which you mention previously. The "dimming" is usually a result of the set detecting NO valid input and hence the dimming / power saving kicks in. Are you ever able to bring up any type of menu?

[scuby]

Re: Bad driver(s)? Sharp LED TV

sorry but your first post talks about a 50 in sharp.... is the one that you are working on with these pictures a 70in? What exactly is the model number?

As far as the "certified good and working"... by who and did you see this?

I wash oping you'd replay as to your success the past.

At the end of post two I specify the model number of this set:

The European model designation is: LC-70LE835E
The US model designation is: LC-70E735U

The certified good is unit supplied by a TV repair tech. There's a warranty and I've already contacted him about "new" unit.

It could be at fault though I'm hesitant to chalk it up to it.

[budwich]

Re: Bad driver(s)? Sharp LED TV

sorry but your first post talks about a 50 in sharp.... is the one that you are working on with these pictures a 70in? What exactly is the model number?

As far as the "certified good and working"... by who and did you see this?

[scuby]

Re: Bad driver(s)? Sharp LED TV

Ok.

So I threw a new Tcon board at it. Certified good used and working.

Photo 1 shows the "best" result with the original Tcon board.

Photo 2 shows the result with the "new" Tcon board.

It's not consistent. If the Tcon was malfunctioning I'd expect replacing it either to remedy the TV by replacing it. If it's not the Tcon i wouldn't expect it to change anything as it does. If it isn't the Tcon I'd expect the "same" malfunction.

To re-iterate: when disconnecting 2 ribbons from either side of the Tcon the TV shows a half white screen.

Reset doesn't get service mode. There is no visible menu. All video signal is missing. Audio is present.

[scuby]

Re: Bad driver(s)? Sharp LED TV

I followed this procedure to reset the set (even though I have no codes).

Unplug set. Hold down Vol - & Input while plugging set back in, release. TV powers up and shows variations of the following image (see attachments). A partial blue screen. Which can hold, flash off for a second and back on. I can't get any menu or other image to show.

After the reset I cannot see a "K" as suggested by some posts.

Hope this helps narrow things down. I can get a Tcon locally quickly relatively cheaply. Is it worth it? Or has this panel suddenly and dramatically died? Astounding how many Sharp Tv's have issues out there!

Please ignore the mess. I'm in the middle of a divorce and living in my office. The TV working would be a good thing come the holiday's lol

thanks again.

PS: with one side disconnected from the Tcon the white side will dimm after a few seconds as if saving power. Hitting the menu button or volume will trigger the screen to illuminate fully again. It seems to respond that much at least. It also does this when displaying the blue screen which varies in size when turned off and on again but is always on the same side.

Hoping for input. Cheers

[RJARRRPCGP]

Re: Bad driver(s)? Sharp LED TV

cheers.

The LE's are the wost offenders in what way? Worst offenders in panel failure?

Yes, they're the worst offenders of panel driver failures, if not also deep into the panel!

[scuby]

Re: Bad driver(s)? Sharp LED TV

allright: here's wat I've done:

I have 4 cable/ribbons running from the Tcon to the panel. My backlights always come on every time I power up the set. I have no codes flashing at any time.

I have a source playing verified by it's audio.

Unplug the right most cable/ribbon: corresponding half of screen lights up mostly white/grey but lot's of colored lines. See Pic 1

Unplug the second cable from right: corresponding half of screen goes completely white. See Pic 3

Same is true of the left. 1 cable results in a more colorful lighting up of the screen. Disconnect both it's all white. See pic 2, it goes fully white like pic 3 on the other side too.

Disconnect all four and the set switches off.

What can we conclude from this?

[scuby]

Re: Bad driver(s)? Sharp LED TV

you should still try doing the "cable removal test" again and feed in an input signal. Depending on the outcome, it will readily point you in a direction.

Ok. I need a clear guide on that test. Could be me but I'm not reading a consistent methodology.

Give it a signal: verified by audio

Remove outer Tcon cable (I have four). That half should go white?

Reconnect and remove opposite and that half should go white?

Don't need to remove the inner cables?

My backlight always comes on. I have no codes flashing.

thanks

[budwich]

Re: Bad driver(s)? Sharp LED TV

you should still try doing the "cable removal test" again and feed in an input signal. Depending on the outcome, it will readily point you in a direction.

[scuby]

Re: Bad driver(s)? Sharp LED TV

Very good question, I don't know if they are all the same, I usually just throw a tcon at it, if cleaning cables don't work, unless it's something very obvious like a bad fuse or such. Not much patience for dealing with the real small components that might be involved.

basically my train of thought too

[scuby]

Re: Bad driver(s)? Sharp LED TV

Being a Sharp, check this thread:

https://www.badcaps.net/forum/showthread.php?t=48477

Series LC-XXLEs are the worst offenders!
(The XX, is the place holder for the 2 digits of the screen size, in inches.)

cheers.

The LE's are the wost offenders in what way? I'm reading a bunch of symptoms/solutions. Worst offenders in panel failure?

Seems so strange to me that the panels fail one moment to the next. I have no codes. I'm still not clear on the Tcon ribbon unplug test that proves a faulty panel (and why/how). Any insight?

Thanks for the help folks. Much apreceated.

[RJARRRPCGP]

Re: Bad driver(s)? Sharp LED TV

Being a Sharp, check this thread:

https://www.badcaps.net/forum/showthread.php?t=48477

Series LC-XXLEs are the worst offenders!
(The XX, is the place holder for the 2 digits of the screen size, in inches.)

[nomoresonys]

Re: Bad driver(s)? Sharp LED TV

Very good question, I don't know if they are all the same, I usually just throw a tcon at it, if cleaning cables don't work, unless it's something very obvious like a bad fuse or such. Not much patience for dealing with the real small components that might be involved.

[scuby]

Re: Bad driver(s)? Sharp LED TV

cheers

some of might be a littel too finnicky for me. I'm a mechanic by trade and the fiddly stuff gets me under my skin

I'll have a good look day after next. Meanwhile I've orderd a Tcon for 22 euro's because, well honestly I'm hoping to throw a part at it and have that work.

I also need to pick up finer pointed probes for my dmm.

Is it worth mentioning that the television is not flashing any error codes? I'm not sure what kind of diagnostic this TV is capable of but perhaps worth noting...

Either way I'll give this all a read over again tomorrow. The Tcon trainng is on a Samsung. am I looking for similar if not identical voltages in and out on my Sharp? Where can I get that information if there are variations?

[nomoresonys]

Re: Bad driver(s)? Sharp LED TV

The tcon training is post #29 there: https://www.badcaps.net/forum/showthread.php?t=76056

[nomoresonys]

Re: Bad driver(s)? Sharp LED TV

Well I don't think you can rule out mainboard, tcon or panel yet, it can be tricky pinpointing a problem, probably why a lot of people start with throwing a replacement tcon at it if they can get one cheap enough, nice testing video here, he checks the power and mainboards over and Budm posted a tcon checking procedure the other day: https://www.youtube.com/watch?v=ocqnqmBxiqY

[scuby]

Re: Bad driver(s)? Sharp LED TV

did you got the white screen when you disconnected the ribbon with signal or with out ? you need with signal to see if half screen come out with picture... if you did it with signal then you have much likely issue on main boards

I disconnected them wihtout signal and with the power off.

I should do this test with the set on and a signal playing?

What am I looking for?

[Diah]

Re: Bad driver(s)? Sharp LED TV

I just disconnected the Tcon ribbons carefully and I was able to get a full white clear screen on each half. The first time the left half was fully white and right half looked like it had been smashed! all kinds of lines and colours. Put it all back, fired the tv up: blank screen again.

Pulled the ribbons again. This time the right half was fully white and the left half mostly grey.

Is it safe to conclude the panel itself is ok?

Bueller?

did you got the white screen when you disconnected the ribbon with signal or with out ? you need with signal to see if half screen come out with picture... if you did it with signal then you have much likely issue on main boards