Yeah, so the problem is likely with the main power supply; check these locations.
RED - Test resistance (power off)
GREEN - Check voltage across (power on)
1. should be around 10V to 15V
2. should be around 115V AC (use AC scale)
If red is OPEN, then the FET is probably short.
If GREEN 1 is low, then the startup cap, charge resistor or a diode on the secondary is short.
If GREEN 2 is low, then AC is not getting to the right part for some reason.
Attached Files
Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.
What is that Green #2, I do not see the connections on the bottom side of the board. And how did you access to measure the voltage on it?
The 19K resistor is for the Snubber circuits.
Can I get pictures of the area in red? I see some traces have corrosion (dark stain).
I have disconnected the two LED connectors and held it vertically.
I will put up some more pictures later on from that area.
There is some corrosion, the tuner for example it's rusted completely.
I'm going to pick up another LG now.
Here it is the Green#2:
But that is GAS discharge tube, that black thing looks like a black rubber bumper. If that is the two points you have measure 62.5VAC, that cannot not be right since that part is in parallel with one of the common mode choke (very low DC resistance, and low reactive reactance) winding, the voltage will be less than 1VAC. You can also see that they did not install another GT on the top section of the choke either.
I think that is just a rubber bumper, I do not believe they stuff the GTxxx in those two locations on the board. The main thing is the AC reading of 60 something VAC at those two pads, it cannot be that high at all.
Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.
Those spark gaps are one of the devices that make the crackling sounds when you plug something in due to the inductor voltage building up rapidly (intermittent contact.)
Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.
I wrote down the ICs markings, and I have found two of them, but not the other three.
The one that I have found is: DDA002C and 1608B.
There are other three ICs which I haven't found yet anything, these are:
DDA003A, 36S3LJ/G1006, 5209/50YS005
For the 1608B here is the datasheet: http://www.datasheetarchive.com/IC+1...datasheet.html
For the DDA002C I have found some pictures:
Voltage across green #1 is too low, check the IC near to it, and see if you can get part #.
Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.
Page 5: "The VCC pin is the positive supply of the IC. The operating range is between 10.5V and 26V."
Check for shorted diodes on the output. Does the supply click or tick at all, approximately a few times a second?
Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.
Comment