Sharp LC 42SV50U green lite

[inwo]

Sharp LC 42SV50U tv displays red lite.
Powers up.
Green lite comes on steady.

No back lite or display.

Will not power down. ie. green lite stays on.

Power supply seems ok.
Back lite works when forced with blon held high.

Any ideas?
Link to service info or diagram?
Reset procedure?

ps.
Set may be new!
Auction item with other new-in-box tvs.

[topng]

Re: Sharp LC 42SV50U green lite

it seem to be the main board.
because she did not turn off
but you never know unequivocally

can u take a picture of the boards
and then we can make suggestions for testing

[inwo]

Re: Sharp LC 42SV50U green lite

Thank you,

Here is main board with cover off.

I'm thinking it's sw issue or needs reset, as power supply comes on.

I haven't checked supply with scope yet. I suppose the +5 supply could be noisy after start-up.

Part out of stock all over. 9JY0142CTK04101

[tom66]

Re: Sharp LC 42SV50U green lite

This is actually an AmTRAN TV, badged as Sharp, like a Vizio. You are probably looking at a bad SPI flash on this model, i.e. corrupted firmware. Potentially there is another issue but this is the most common with AmTRAN boards.

[inwo]

Re: Sharp LC 42SV50U green lite

Thank you.

Any advice?

[tom66]

Re: Sharp LC 42SV50U green lite

Locate and replace SPI flash if there are online retailers selling it or you can get a BIN file and you have a programmer.

Before doing this I'd recommend checking voltage regulators on the board, and DC-DC converters

[inwo]

Re: Sharp LC 42SV50U green lite

Maybe this can help some one else.

Go to:http://m.sharpusa.com/CustomerSuppor...50U&print=true

Save this file to usb device. "Firmware for LC-42SV50U"
Does not seem to be zipped or PW protected.


Don't follow these directions:https://cdn.badcaps-static.com/pdfs/...ac1ee02094.pdf


Plug device with saved file into tv usb port.
Plug in tv.
Turn on tv.
USB lite will start blinking.
TV lite is green and does not blink.

TV rebooted and seems to be working. I'm waiting for auto tune to find a signal.

[tom66]

Re: Sharp LC 42SV50U green lite

Nice. So it was corrupted firmware as suspected, good to know you can reflash it easily, I guess AmTRAN learned from the previous many bricked Vizio sets...

[budm]

Re: Sharp LC 42SV50U green lite

Thanks for sharing the tips.

[inwo]

Re: Sharp LC 42SV50U green lite

Nice. So it was corrupted firmware as suspected, good to know you can reflash it easily, I guess AmTRAN learned from the previous many bricked Vizio sets...

Yes,
Thank you!

I'm pretty good with hardware.
But lost otherwise. The online instructions being wrong didn't help.
If it didn't pretty much fix it's self I would have no idea.

I had nothing to lose and just blindly tried everything.

I'm sure some searches will find this fix.
That's what I do.

[events.b]

Re: Sharp LC 42SV50U green lite

Hi,

I have the same exact TV with the same exact symptom. I plug in the TV and have red standby light. I turn on the TV and have the steady green light, but no backlight. I have not tried forcing the backlight on yet. I tried the firmware update instructions posted above, but in my case, after the USB light was blinking, the TV would just cycle between red/green and do nothing. Do I need to wait longer for the update to complete or is that a signal that the update didn't work?

PS, just to be clear, I place the .pkg file on the root of my USB stick and thats it? Doesn't matter if other files are on the USB stick as well?



EDIT: I was impatient and didn't wait long enough. THANK YOU! Fixed the TV. Seems to be working now

Thank you

[selldoor]

Re: Sharp LC 42SV50U green lite

I would try again with an empty stick - does it say in manual what to format it to- Fat32?

[events.b]

Re: Sharp LC 42SV50U green lite

For clarification, I used an old 128MB stick that was formatted FAT32. It did not matter if there were other files on the stick. Just put the .pkg file at the root of the stick. The TV WILL flash red/green while updating, but this is OK

[inwo]

Re: Sharp LC 42SV50U green lite

Same tv came back.
I forgot about this fix until google brought me back.
Worked again.

Thanks again!

[mmartell]

Re: Sharp LC 42SV50U green lite

Just received one of these for free and flashing fixed it ! Thanks for the tip.

[kdh2012]

Re: Sharp LC 42SV50U green lite

Hey Guys - great fix!

I just had one of these tv's come in with a near shorted main chip (~6 ohms).

Replacing the IC got rid of the short, but the tv still did not work. Reloading the memory did it!

Since someone had a tv come back. I wonder if this IC starts using too much power and causes the corrupt memory?

The IC is a MEDIATEK - MT5389FUNU. Found one for about $15 shipped. It's 256 pins of touchy soldering ...

Thanks again!

[Baron7]

Re: Sharp LC 42SV50U green lite

Hi i have the same problem, and I apply the fix that you posted and work very well thank

[huron]

Re: Sharp LC 42SV50U green lite

Found the TV on a curb side. Same problem, the flashing fixed it!!! Instead of going to a landfill, now it has a home!

[Artamov]

Can someone share the firmware file? The website listed here is long dead, and I've had no luck with google or searching through sharp websites. I have this TV, and it works every 4 or 5 tries. I get picture, sound, menu - but most of the time the screen stays black. The green power light comes on, nothing on the screen, no sound, and then it won't turn off. This thread made me excited, but now I just need the firmware. THANK YOU!!

[Artamov]

Can someone share the firmware file

Calling Sharp was useless, but the online chat agent did send me the firmware (attached). Hope this helps someone else with the same issue!