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Old 06-18-2017, 10:56 AM   #1
Rickig
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Default 50/209 backlight issue

Hi all
I have the above mentioned tv
Symptoms are tv powers up and comes on with backlights for approx 10s then backlights drop out.
The led driver has constant 5v to blon and 24v to vbl but voltage out drops from 53v to 24v when the lights go out.
If I disconnect blon and refit whilst power is on the backlights come back on for 5s then shut off again.
If I disconnect one of the two ribbon to the back lights the back lights donas expected and flash On then straight off.

The fact that they come on and stay on for a little while makes me wonder if it's the led driver at fault.

Any thoughts?
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Old 06-18-2017, 12:22 PM   #2
Rickig
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Default Re: 50/209 backlight issue

Update... tv is now working.
Disconnected tcon and the tv backlights came on and stayed on.
Reconnected tcon but disconnect ribbons, same... on and stayed on.
Reconnected ribbons one at a time and tried... on and stayed on.
Reconnected both ribbons so all back to how it was.... tv is on and staying on... not sure what caused it but suspect a bad connection on the tcon ribbons.

What's your thoughts?
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Old 06-18-2017, 04:54 PM   #3
budm
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Default Re: 50/209 backlight issue

Can we see the pictures of the whole backside of the TV showing how all the boards are connected together?
What is the make and model of the TV?
I have no idea what 50/209 is.
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Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956

Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999

Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl

Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/

TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
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