LG 42ld520 Main Board issues

Smoothjazz

Member

Join Date: Feb 2017

Posts: 13

Country: United States
#1

LG 42ld520 Main Board issues

01-13-2018, 09:28 AM

Been troubleshooting this LG tv set this morning.I get the LG startup screen..with no clock.. the screen suddenly goes away with only the back light
lit up.Took DC voltages on the main power supply board which has the connection going to the main board and I am missing a couple 20VDC readings which
is suppose to be on certain pins coming from the power supply board. Has anyone came across schematics for these power supply boards to try to troubleshoot
voltages? The board has markings on what voltages are suppose to be at certain points.

Last edited by Smoothjazz; 01-13-2018, 09:36 AM.
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budm

Badcaps Legend

Join Date: Feb 2010

Posts: 40746

Country: USA
#2

01-13-2018, 03:34 PM

Re: LG 42ld520 Main Board issues

We need pictures of the whole back side of the TV showing all the board.
We also need the Voltage reading of the connector on the power supply board end that goes to the main board when TV is OFF and when TV is turned on, you MUST out down the pin name for each pin and follow by the Voltage readings for each pin.

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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Smoothjazz

Member

Join Date: Feb 2017

Posts: 13

Country: United States
#3

01-14-2018, 06:26 AM

Re: LG 42ld520 Main Board issues

Will do
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LG 42ld520 Main Board issues

LG 42ld520 Main Board issues

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