Sharp Aquos LC-42D62U Display Output Problem

[Hobby 1]

Re: Sharp Aquos LC-42D62U Display Output Problem

OK. This is my experience with these main boards. First of all, they can fail on their own, no voltage spike or death rays from Mars needed. Second, all the processing takes place on this main board. A different revision level should still work. It never bothered the sets I worked on. A different revision level will have more or less features. I have upgraded sets by changing the main board from a D72 to a D62 set. The difference is 6 inputs instead of 5. And they don't look alike and they originally came from differnt sets. They are also interchangable between the 42 and 46 inch sets and these sets use completely different power boards! One thing I noticed is the heat sink is missing on both boards. Did you run them with the heat sinks off? I hope not. The board with the extra long connector is supposed to have 3 jumpers in it. I have several versions of this board, some good and some bad. I usually exchange them with the lower input board and side panel. Takes less time. And I don't remove any jumpers.

As far as ebay boards go. I have gotten some good boards, some wrong boards (they don't know what they are selling) and some bad boards. They don't test them, just strip them out of damaged sets and in many cases, they don't use good anti-static practices. They rarely ship them in anti-static bags.

Complain to the seller, they would rather refund your money/send another board than get a bad review where you tell potential buyers that they sell defective untested boards. I avoid the sellers that wasted my time/money.

[Hobby 1]

Re: Sharp Aquos LC-42D62U Display Output Problem

Here is a closeup of the extra connector with jumpers.

[crepiduse]

Re: Sharp Aquos LC-42D62U Display Output Problem

I forgot that that board did have the jumper set on a different revision..... If the boards were ran without heat sinks (good notice hobby1) then they're likely damaged. However if not, then installing the jumper should fix the issue. Thank you Hobby1 for correcting me on this one. I was not thinking when I mentioned it as normally they're not interchangeable, however in this case, they are.

[Hobby 1]

Re: Sharp Aquos LC-42D62U Display Output Problem

If you did not run the set too long with the heat sink off, it may not be permanently damaged. When the chips get hot, they lock up, just like cpu chips in computers. They may work again. Put the heat sink back on and try.

BTW, these are great sets to work on. Lots of units out there for parts. I have the 46 and 42 inch versions, both upgraded to the D72 edition. And lots of spare parts from broken screen sets.

[trusean]

Re: Sharp Aquos LC-42D62U Display Output Problem

Thanks for the continued info. And no, I did not run the set with the heat sinks off. I just did that for the pics. My old board did not have any jumpers on it while the new board appears to need jumpers. As seen in your pic, just above the part number, you do indeed have it clipped in. My 2nd test board, which is very similar to yours, did not come with that small input cable, the jumper. So could it be that the jumper is needed for the new board to work? If so, i'm thinking that this kind of part may be very hard to find.

[crepiduse]

Re: Sharp Aquos LC-42D62U Display Output Problem

Just make the jumper and it should work.....

[trusean]

Re: Sharp Aquos LC-42D62U Display Output Problem

Here is a closeup of the extra connector with jumpers.

If I am able to find the 14 pin male connector, is the wire sequence as depicted?

[crepiduse]

Re: Sharp Aquos LC-42D62U Display Output Problem

That is correct.

[csadat]

Re: Sharp Aquos LC-42D62U Display Output Problem

i am having the exact same problems that you are, except i have changed the power supply, inverter boards, main video and av board. I have installed all one at a time had still just get the flashing green power light after having the screen go white and then turn off again. The only thing i haven't changed yet is the t-con board. Have you had any luck with you tv?

[csadat]

Re: Sharp Aquos LC-42D62U Display Output Problem

Also i hold down the + VOL and the down Channel button and plug in the power cord, the set turns on the screen goes grey sometimes white, then turns off but the power light stays on and the volume works if you hook up a dvd player but still no pic. I dunno maybe this is a different reset or something. Does yours do the same?

[trusean]

Re: Sharp Aquos LC-42D62U Display Output Problem

Also i hold down the + VOL and the down Channel button and plug in the power cord, the set turns on the screen goes grey sometimes white, then turns off but the power light stays on and the volume works if you hook up a dvd player but still no pic. I dunno maybe this is a different reset or something. Does yours do the same?

My TV does the same thing as you describe. However, I do not have the jumper cable installed on my main board so I don't know what will happen if I do install one. I really don't think I will ever find the part. As far as making one, I talked to a repair shop tech and he said that only Sharp uses the male/female connector I need to make the jumper. So unless I can find one on the net, I'm sure I just bought a paper weight. Was your original screen problem the same as mine (the pics are on the first page)?

As far as the tcon board, I am not sure. But if you have changed every board, I guess that only leaves the tcon. If it were me and that didn't solve the issues I'd probaly smash the set.

[csadat]

Re: Sharp Aquos LC-42D62U Display Output Problem

I have tried that reset i told you about with and without the jumper on my board and it didn't make a difference. also after i do that reset if i turn the power off and on by the power button on the tv, it gives a different colour on the screen each time i turn it on and off. I'm getting pretty close to smashing it.

[csadat]

Re: Sharp Aquos LC-42D62U Display Output Problem

I have asked someone on a different website forum for ideas and one guy said it might just be a problem with the firmware. He then gave me a website where i can find the newest firmware for it, however i no longer have the manual for the TV and don't know how to install it. do you have the manual still? and if so does it say anything in it about firmware updates?

[retiredcaps]

Re: Sharp Aquos LC-42D62U Display Output Problem

I'm getting pretty close to smashing it.

You do know that people will pay $$$ for it on your local craigslist or kijiji. Some TV repair shops will also buy it for $$$. Both parties buy it for parts.

[csadat]

Re: Sharp Aquos LC-42D62U Display Output Problem

My original screen problem was never the same as yours it just turned off one day and gave me the flashing power light.

[csadat]

Re: Sharp Aquos LC-42D62U Display Output Problem

Thanks retiredcaps for the info, i did know that and was only kidding about smashing it.

[Hobby 1]

Re: Sharp Aquos LC-42D62U Display Output Problem

I've been off this site for a few days and I see these new problems pop up here. Simple things first. Get the sets back to the original problem. Label original boards. Label replacement boards. If the replacement boards came from ebay or similar places, they may be defective to begin with. The flashing LEDs are an error code. The reset procedure clears the error code and tries to fire up the set again. Some error codes prevent the set from turning on unless cleared or repaired.

Don't smash sets in frustration. If the screens are not damaged, the sets are saleable for more than a set with a smashed screen.

A common sympton of a bad T-con board is a grey lit screen with no picture or menu. Disconnecting the main cable to the T-con board gives you an all white screen (same as a blown fuse on the T-con board). Don't install new firmware if you have nothing on the screen....

Check power supply voltages on the power boards. Are they in spec? I have never had bad caps on a Sharp board, bad voltages, yes.

And take a break for the holidays.

[trusean]

Re: Sharp Aquos LC-42D62U Display Output Problem

Update: The new psu has arrived.

I will call my original components 1 and the new ones 2.

So I tested the set in the following arrangement with the following results.

psu 1 with main 1: org. problem as described
psu 2 with main 1: org. problem as described
psu 1 with main 2: new problem as described
psu 2 with main 2: new problem as described

From this I can guess that the issue is not the psu because both of them produce the same original problem as well as the same new problem. So I either bought a bunk main board or they are not interchangeable and the one I purchased is wrong. I am lost at this point. I think I will try to get refunds for both boards (minus shipping and restocking costs) and purchase a main board that is exactly the same as mine. I have found one online (I wish I found it sooner). In the mean time, I do have another main board on its way but I doubt that one will work as its the same one I have bought and it too will not come with a jumper. Arg!

[trusean]

Re: Sharp Aquos LC-42D62U Display Output Problem

I got the second main board in today without a jumper. Put it in the set and now a third problem. The red lights on the main board do flash and there is power to the psu. But all that happens is the TV's relay turns and nothing happens. Then after about 20 sec. the relay turns again (click). It does this three times and then stops trying. During this time the screen remains black. No light flicker of any kind. Also, the front LED lights do not come on at all.

I can come up with three ideas.

1. The main boards are not interchangeable.
2. Both boards that I bought are malfunctioning.
3. They won't work without a jumper.

Either case, I can assume that the only solution is to buy the main board that is exactly the same as mine, regardless of the part number as they are all the same.

[gamethriller]

Re: Sharp Aquos LC-42D62U Display Output Problem

I was able to reflow my mainboard for the 42" Sharp. I used a heat gun and liquid flux no clean.