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Equipment Repairs => LCD TV forum => Topic started by: lothian on November 20, 2019,11:06:33

Title: Sony XBR-49X700D: Vertical Lines
Post by: lothian on November 20, 2019,11:06:33

Sony XBR-49X700D
Manuf: 2017

Yet another post complaining about vertical lines in an LED TV...

I have a Sony XBR-49X700D that decided one day to display a black screen and the dreaded "Sony Six Red Blinks". I buried my face in my hands, fully aware that the "Sony Six Flash" error code typically means either of two things: a failed T-CON board, or--more likely--one or more dead backlight LEDs. Bleh.

So I did the easiest thing first: I swapped the T-CON board with no change in status. I heaved a plaintive sigh, and began the onerous chore of dismantling the TV to get at the LED backlight. Sure enough, one of the LEDs in one of the boards tested dead. I replaced the bad LED strip with new. The backlight array now works perfectly and there is no red blink code.

However...

Now the display has vertical lines on both sides and a large swath of grey cuts along the middle (see image). Vertical lines typically are caused by a bad T-CON board and/or a poor ribbon cable connection. I swapped between two T-CON boards and re-seated the two ribbon cables that connect the T-CON to the panel--no change.

Surely there's some simple thing I've overlooked. I am stumped. I can't imagine a formerly working panel is now broken to this extent.
What causes vertical lines? What else should I check?

Title: Re: Sony XBR-49X700D: Vertical Lines
Post by: Davy on November 20, 2019,13:51:17

Could be Tcon as you say or the Tcon connectors, crimps can be a pain at times for either oxidizing or coming loose or the screen itself, the connections from the Tcon on to the plastic ribbon that connects to the screen.... sometimes pressing hard with thumb, running round the edge of the front trim top and bottom might reveal the problem, heard of folks packing foam between the ribbon cable and the trim.

Dave

Title: Re: Sony XBR-49X700D: Vertical Lines
Post by: downunder on November 25, 2019,05:07:33

Try my suggestion for the post "LG 55LA6208 Panal Problem".                             Bruce

Title: Re: Sony XBR-49X700D: Vertical Lines
Post by: lothian on December 09, 2019,09:47:44

i see your entry in the LG 55LA6208 - Panal Problem (https://quuq.org/forum/index.php?topic=10711.0) thread--but it's blank.

what is your suggestion?

Title: Re: Sony XBR-49X700D: Vertical Lines
Post by: downunder on December 10, 2019,02:15:31

Well, I see it! It involves disconnecting the t-con- to- panel connections one at a time and note the picture (or lack there-of) each time.

Title: Re: Sony XBR-49X700D: Vertical Lines
Post by: lothian on December 10, 2019,14:31:26

Gotcha.
The inference being, have I tried all the common sense stuff; i.e., disconnect/reconnect LVDS cables, clean connectors/connections, check edge bonding of each FPC panel connector? Answer: Yes. No difference. What else ya got...

Title: Re: Sony XBR-49X700D: Vertical Lines
Post by: downunder on December 11, 2019,02:53:49

The 2 flexy cables from T-con to panel. Remove 1 only and observe the screen. The disconnected side will give a pure white 1/2 screen
(which is good) or the screen will be full of artifacts. Then reconnect that flexy and remove the other. DO you now get a white 1/2 screen or rubbish . In either case. rubbish means the panel has been somehow damaged -this includes the strip boards along the bottom.