lg 43uh610v schematic

[vikivng]

Hi guys,
can anyone help me with a schematic for this tv.?
Im getting solid red standby light with one blink when power button is pressed.
Power supply seems fine.
thnx

[budm]

Re: lg 43uh610v schematic

You will get a lot more help if you upload good clear pictures of the whole back side of the TV showing all the boards.
"Power supply seems fine." Seems fine???
Are you getting the correct Voltages and correct control Voltages?
You need to report the Voltage readings of each pin of the power supply connector that goes to the main board when TV is OFF and when power switch is activated.
You MUST PUT DOWN PIN NAME AND FOLLOW BY THE VOLTAGE READING FOR EACH PIN so we can easily see what it has or does not have.

[vikivng]

Re: lg 43uh610v schematic

Yes..Sorry guys.
you are correct..
Iwill do that now.
thnx for the reply.

[vikivng]

Re: lg 43uh610v schematic

Voltages taken without pressing power button but with tv plugged in.
Standby light is on.
P DIM 1= fluctuates between .4 - .6v
GND=0V
NEXT PIN DOWN FROM GND fluctuates between 5.4-6.9V
NEXT PIN DOWN fluctuates between 5.4-6.9V
gnd=0v
PWR- ON = 0V

Pressing power button gives PWR-ON 3.1V FOR SPLIT SECOND.

[vikivng]

Re: lg 43uh610v schematic

Does this make sense.?
thnx

[budm]

Re: lg 43uh610v schematic

13.2V power supplies and PWR-ON should not be going up and down.
I cannot see the power supply board P/N. I need good clear straight shot hi-res pictures of the whole power supply board
What Voltages do you get on the 13.2V pins if you do not have the power supply board connected to the main board.

[vikivng]

Re: lg 43uh610v schematic

HI ,
WITH power disconnected from mainboard
DIMM PIN is now 3.7v
13.2 pins both constantly fluctuate between 3.4-5.7v
thnx

[vikivng]

Re: lg 43uh610v schematic

ok I can see these pics wll not be good enough to scrutinze.
Sorry.
I will upload more i n the morning with my slr.

[budm]

Re: lg 43uh610v schematic

HI ,
WITH power disconnected from mainboard
DIMM PIN is now 3.7v
13.2 pins both constantly fluctuate between 3.4-5.7v
thnx

OK, looks to be something in power supply problem at this point.
Disconnect the LED connector and see what will happen to the 13.2V pins.
BTW, I also expect the DIM pin Voltage to be unstable also since the 13.2V is not steady.
Inspect the solder joints of the power supply board real well to see if it has bad/cold solder joints or not.

[nomoresonys]

Re: lg 43uh610v schematic

Also check all your diodes.

[vikivng]

Re: lg 43uh610v schematic

Hi,
so I tested all the diodes and checked the joints..
The joints of what seem to be the coils have some black oily like residue ..Not sure if this normal or not.
No change in voltages.
Could the capacitors be the cause.?
How would I check the voltage of the main filter cap?

[nomoresonys]

Re: lg 43uh610v schematic

Set meter to 200 vdc, negative probe on negative leg positive on positive leg, BE VERY CAREFUL not to touch that area with your hand, this is the HOT/DEADLY side of the board, check it in standby, then check it after you power up the tv.

[vikivng]

Re: lg 43uh610v schematic

Thnx.
so I had to set meter at 1000 to get any reading which was 330v.
Wout that be normal?

[dick_barton]

Re: lg 43uh610v schematic

Have the components in the red boxes had their pins cut. One of the connections does not look right.

[vikivng]

Re: lg 43uh610v schematic

Hi,
yes. They were cut and resoldered above the board.
Continuity checked.

[vikivng]

Re: lg 43uh610v schematic

AT this stage,
is it definitely the power supply with these voltages.?

[vikivng]

Re: lg 43uh610v schematic

Hi guys
im guessing cutting and resoldering above the board is bad practice.?