Sharp Aquos LC-46D64U stand by with new boards!

[eTanium]

Re: Sharp Aquos LC-46D64U stand by with new boards!

So, at this point, the problem can fall under two categories (or a combination of the two).

A) Software/firmware errors which can't be fixed/cleared/flashed via the USB firmware update (possibly due to another board's hardware failure).

B) A hardware failure.

C) Combination of A&B.


As for 'B', the only boards that haven't been replaced, are the 4 inverter boards and the t-con board. The power supply board was replaced, but didn't fix the issue, so I returned it. If it was faulty in combination with the bad main board/tuner board, then I will still need to replace the old power supply board that is in the TV. Although I don't think the power supply board is wrong (please let me know otherwise), I am willing to test it with the meter wherever necessary as I am directed to do.


I am willing to test anything on the inverters and such as well; I just need some hand holding. There was mention of testing a few components on these boards earlier, but I was weary of trying them (due to high voltage and such); I had hoped that changing out the main board would alleviate the problem.


Where should I check next?

[eTanium]

Re: Sharp Aquos LC-46D64U stand by with new boards!

bump

[cashkennedy]

Re: Sharp Aquos LC-46D64U stand by with new boards!

Earlier when you said your getting 3v to the side board, it hit me that you need 5v for usb devices, so the motherboard should have a regulator to create 5v somewhere, unless the power supply creates enough 5v. Granted it might not send the power to the side board for the USB till you have the set fully on.

But if you wanted to try to trace the 5v back, the outer 2 pins in the usb socket are the 5v and ground. 1 should cause your multimeter to beep(0 resistance) when you have it on 200 resistance and you test 1 pin in the socket and touch a peice of metal with the other probe. (this is with tv off). And the other outer pin in the socket would be 5v then, and you could trace it it back through the side board to the mainboard and see if you can find a regulator (small black device with 3 wires) connected to it.

Post a picture of the top left inverter if you want some sugestions on what to test there, and if possible the back of that inverter too. (its labeled as inv-1 in the diagram)

[Legend320]

Re: Sharp Aquos LC-46D64U stand by with new boards!

Etan. Just read the whole post. Was wondering did you ever find a solution? I have the same exact tv and have the same exact problem.

[eTanium]

Re: Sharp Aquos LC-46D64U stand by with new boards!

Negative. Am looking to fix another TV or buy a new one. I would have to replace the glass screen/LCD panel to get this one working =/

Good luck!

[Legend320]

Re: Sharp Aquos LC-46D64U stand by with new boards!

Sorry to hear that. With mine I think it's one or all the inverter boards. I can get the tv to turn on and go thru different inputs. As soon as I select an input the tv goes black. I can select menu only when I'm on input 7. I can go thru all my menu options fine. One thing I noticed on the back of the main board there is a small tiny red light blinking. No idea what this means. Maybe the main board is bad. I've tried hooking my laptop up to the input 7 but once I do that the screen goes blank. Sharp is not so sharp.

[eTanium]

Re: Sharp Aquos LC-46D64U stand by with new boards!

Sorry to hear that. With mine I think it's one or all the inverter boards. I can get the tv to turn on and go thru different inputs. As soon as I select an input the tv goes black. I can select menu only when I'm on input 7. I can go thru all my menu options fine. One thing I noticed on the back of the main board there is a small tiny red light blinking. No idea what this means. Maybe the main board is bad. I've tried hooking my laptop up to the input 7 but once I do that the screen goes blank. Sharp is not so sharp.

Well it sounds like yours isn't as far gone as mine is! I wasn't able to even get it to boot to the input.

I bought a replacement main board and it too had a red blinking light, where the original didn't. Still, I don't think that means it has a bad main board, just that there is an error somewhere, and the main board recorded it.

Again, I gave up on fixing mine, due to the fact that the LCD panel is worth more to replace than buying a new TV. If you can see any picture at all, including the input selection display, then it isn't your LCD panel.

If you're interested in my TV for parts, I'm sure that you'd find what you need to fix your TV. I even have a few extra parts; I was a bit hasty and bought replacement parts without doing the proper testing first.

Let me know.

[tristan7zavier]

Re: Sharp Aquos LC-46D64U stand by with new boards!

Hi everyone I think i can shed some light on this issue. I was having the same problem with this tv as the op, I changed the powersupply tried all the resets yada yada. I noticed that i was not getting any voltage readings from the pin marked as panel power, from neither powersupply or signal board. I run a small shop that does bga rework for laptops game consoles ect ect.. As a last ditch effort I decided to reflow a chip on the signal board the one under the big heat sink marked broadcom so i put it on the achi ir pro ran my laptop lead free profile. After it cooled I re installed it an plugged it in i heard a relay click once i hit the power button an the set came to life! This is the 2nd sharp aquos tv I have had to reflow. It seems like this is becoming a more common issue with the changing technology.

[mxsteve751]

Re: Sharp Aquos LC-46D64U stand by with new boards!

hello , i have read this entire post and have a similar problemwith my set and have a fairly simple question. i am trying to rule out the possibility of a bad backlight or lcd panel in which case this tv would not be worth fixing.

no display, flashing opc and power light. dont see any obvios problems on any of the boards. i do not have the 12v dc and 60v dc at the the inverter board pins. but if i disconnect the inverter board connectors i do get the 12v and 60 v but upon pluging them back in the relay cycles back off and i lose the 12v and 60v

[hd77shovel]

Re: Sharp Aquos LC-46D64U stand by with new boards!

what is the best way to test an inverter board? there are 4 of them in this TV and I don't want to buy the wrong one or all 4.

[georgebailey23]

Re: Sharp Aquos LC-46D64U stand by with new boards!

How do you reflow?

[pallain]

Re: Sharp Aquos LC-46D64U stand by with new boards!

Anyone every try reflowing after seeing this old post?

[bruceleeworldwide]

Re: Sharp Aquos LC-46D64U stand by with new boards!

very sorry no results still.

[Topher265]

Re: Sharp Aquos LC-46D64U stand by with new boards!

Well, I've got a Sharp LC-42D64U with what sounds like exactly the same problem. There's another thread around here with the 52" version and it had a very similar problem too.

Instead of starting another thread, I'm going to first try a couple more measurements and see where I can get. I've got spare boards I'm working with to try and save this old thing, and I may even try a reflow just for fun. I'd much rather save it and get use out of it instead of adding it to a landfill.

[landen_michael77]

Re: Sharp Aquos LC-46D64U stand by with new boards!

I Will Be A S.O.B. !!!! Reflow worked on a LC-46D85UN

[jdlowvoltage]

Re: Sharp Aquos LC-46D64U stand by with new boards!

Not sure if anyone is still on here... I have the 52" version. Nothing bit a blinking green LED. Can do the input and volume down button while powering it up and it actually comes on for a split second and I see an image. Then clicks and turns off to blinking green light.... possible reflow??? Not even sure what that is or how to do this. I am handy with soldering though. Any ideas?

[jdlowvoltage]

Re: Sharp Aquos LC-46D64U stand by with new boards!

I should also mention that I did replace the power board with same results. I have unplugged all boards from the power supply board except the main board. All with the same results... not really sure how to check the inverter boards

[augiedoggy]

Re: Sharp Aquos LC-46D64U stand by with new boards!

I should also mention that I did replace the power board with same results. I have unplugged all boards from the power supply board except the main board. All with the same results... not really sure how to check the inverter boards

I have the same set as I mentioned in the other thread and also made the mistake of replacing the power board... for me though I was able to unplug the inverters and the set powered on with the light on the main board.. then by plugging in the inverter boards one by one I found #3 is bad although it looks fin.. likely a bad mosfet.

[jdlowvoltage1]

Re: Sharp Aquos LC-46D64U stand by with new boards!

I recently narrowed a the problem down to a bad inverter board on the 52 inch model. The main inverter board actually send a feedback to the main board if it detects anything wrong on itself or the other 3 boards. One of the 4 pin connector (LB) that comes off the main to the first inverter board is the (error) signal that looks for 3v when everything is good. I was actually able to take the other conductor 3v power to the inverter, split it off and jumper it to the error conductor. This faked the tv into thinking inverters were good. Holding the VOL down and input button I powered it up and everything came on and stayed on... I could then see flicking on one side on the secondary inverter board which was the culprit. Long story short. By bypassing the error signal on the inverters andthe tv working told me that it was indeed the inverters. See link.

https://drive.google.com/open?id=1c8...E63ds5OpT-nQr7

[jdlowvoltage1]

Re: Sharp Aquos LC-46D64U stand by with new boards!

Thanks Augie. So my next question is then do you know how to test the individual Mosfets? I was going to replace the board but for some reason it is as rare as a holographic Pokemon lol. The ones on ebay are $80. i would much rather repair the board. I'm very good with a soldering iron. Just need some guidance on testing. i also have the manual which has all part#s. My second option is to convert it to LED using LED strips out of a 50" LED... I would like to try repairing first. Any help is appreciated.