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Old 12-01-2015, 03:16 AM   #1
safesurfer65
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Default Panasonic 48" LED TV, backlight on but no picture

Hello all

Have a Panasonic 48" LED TV model no. TX-48AS640B. Just over 1 year old. When switched on the backlight comes on but no picture is displayed. Can hear the menu being navigated. Suspecting main board, any ideas ? Hope someone can help.

thanks

Mal
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Old 12-01-2015, 10:47 AM   #2
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Check for voltage on both sides of the TCON fuse. It should be near one of the connectors
going to the main board. If you send a clear picture of the TCON board we should be able to point it out. (it's the one at the bottom of your picture) There should be 12V or 5V on both sides of the fuse. Some nay not have a fuse though.
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Old 12-01-2015, 11:14 AM   #3
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Hi

Thanks for that. Think I identified the fuse (circled). 12v both sides !
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Old 12-01-2015, 11:36 AM   #4
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Try having one ribbon cable between the T-CON and the LCD panel connected one at a time to see what you get on the screen.
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Old 12-01-2015, 11:56 AM   #5
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Hi

Tried disconnecting individual and both cables from the T-con to the screen. Made no difference.

thx
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Old 02-04-2017, 11:27 AM   #6
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Exclamation Re: Panasonic 48" LED TV, backlight on but no picture

Hi all been a while I too am facing this blank screen issue on same tv any info and tcon fuse tests fine
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Old 02-04-2017, 02:56 PM   #7
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Default Re: Panasonic 48" LED TV, backlight on but no picture

You have lost too the warranty proof?? :-)
The defect seem sto stay on tcon, can someone pubblish a shopjimmy picture of that board? i can't connect to it.
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Old 02-04-2017, 04:17 PM   #8
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Default Re: Panasonic 48" LED TV, backlight on but no picture

recently done a 40 inch panasonic with bad LEDS just a thought though
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Old 02-04-2017, 05:11 PM   #9
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Quote:
Originally Posted by sordids999 View Post
recently done a 40 inch panasonic with bad LEDS just a thought though
Backlight on no picture......
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Old 02-05-2017, 04:36 AM   #10
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Quote:
Originally Posted by ReeceyBurger123 View Post
Backlight on no picture......
opps i must read more before posting
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Old 02-05-2017, 04:45 AM   #11
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Quote:
Originally Posted by sordids999 View Post
opps i must read more before posting
Lolol
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Old 02-05-2017, 07:17 AM   #12
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Jesus Christ that smokes? That changes capacitors?

Also Jesus Christ chooses... PANASONIC...

Last edited by Davi.p; 02-05-2017 at 07:18 AM..
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Old 02-21-2017, 05:59 AM   #13
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Hi has anyone resolved this issue I've tried tcon and to no Avail have the new main board so will post back when fitted
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Old 02-21-2017, 06:27 AM   #14
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Keep us updated
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Old 02-21-2017, 10:28 AM   #15
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Default Re: Panasonic 48" LED TV, backlight on but no picture

well thats the main board and tcon replaced for good working ones and still nothing but a blank screen

also checked out all screen tabs etc no damage faults etc
im starting to think its the psu but nothing visual or blown

does any have a service manual or know the voltage the power board gives to main
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Old 02-21-2017, 10:34 AM   #16
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Fuse on panel FRP boards?
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Old 02-21-2017, 10:50 AM   #17
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Default Re: Panasonic 48" LED TV, backlight on but no picture

fuse on frp where is this fuse like mate
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Old 02-21-2017, 11:10 AM   #18
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Located in the long boards that are attached to the panel itself. They are concealed within the frame.

Of course this is just a hunch. I have seen panels that have fuses built on to these boards as a precautionary secondary step incase t-con fails

Last edited by freakaftr8; 02-21-2017 at 11:13 AM..
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Old 02-21-2017, 09:35 PM   #19
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Default Re: Panasonic 48" LED TV, backlight on but no picture

Are you sure the backlight is present like OP?
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Old 02-22-2017, 03:01 PM   #20
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Default Re: Panasonic 48" LED TV, backlight on but no picture

I recently had Vestel type 48" Toshiba with backlights ok but no video. Turned out to be the PSU though I didnt get to component level
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