LG 55GA6400 Power Ok, No backlight, No image.

alfredomfr1

Badcaps Veteran

Join Date: Oct 2014

Posts: 318

Country: usa
#1

LG 55GA6400 Power Ok, No backlight, No image.

11-21-2017, 03:07 PM

TV LG 55GA6400
No backlight, no image on screen (checked with a flashlight).
Good: 12v ok, 24v ok, Pwr-On: 3.3v, Main Capacitor: 396v
Bad: A-Dim: 0v, P-Dim: 0v, Drv-On: 0v
Attached Files
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budm

Badcaps Legend

Join Date: Feb 2010

Posts: 40746

Country: USA
#2

11-21-2017, 04:38 PM

Re: LG 55GA6400 Power Ok, No backlight, No image.

Main board is not sending the command signals for the backlights circuit.

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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alfredomfr1

Badcaps Veteran

Join Date: Oct 2014

Posts: 318

Country: usa
#3

11-21-2017, 06:21 PM

Re: LG 55GA6400 Power Ok, No backlight, No image.

Main Board defective ?
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budm

Badcaps Legend

Join Date: Feb 2010

Posts: 40746

Country: USA
#4

11-21-2017, 07:23 PM

Re: LG 55GA6400 Power Ok, No backlight, No image.

That is what it looks like.

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
Comment

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LG 55GA6400 Power Ok, No backlight, No image.

LG 55GA6400 Power Ok, No backlight, No image.

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