Dead 19" LG Flatron

[Solder Boy]

Re: Dead 19" LG Flatron

Hi Bill sorry for the delay in getting the photo to you.. the original pic is 4000x2256 it is sharp and clear but clearly too big as an attachment.

Hope this pic is good enough for you.. if not let me know

Thanks

[PlainBill]

Re: Dead 19" LG Flatron

Hi Bill sorry for the delay in getting the photo to you.. the original pic is 4000x2256 it is sharp and clear but clearly too big as an attachment.

Hope this pic is good enough for you.. if not let me know

Thanks

Nope, doesn't work. The contrast is better, but it's too small to be useful for me. It appears they are using both 5V and 12V to regulate voltage the output??? Check the resistor just below U201, R206?

Here's my suggestion. Vueprint Pro is now free. Use that to crop the original picture and if necessary, reduce the size. When you download it , don't forget to make a note of the serial number (15551888) to run it.

PlainBill

[Behemot]

Re: Dead 19" LG Flatron

Just got this display, same symptoms. The Samxons GF seem to be somewhat like KZG for Chemi-Con - low price, barely hold spec'd lifetime. Ideal for dispaly manufacturers.

I found no but input fuse so the current is definitelly not broken anywhere. FETs and diodes seem to be fine. Output voltage with no load is 4,9 and 16,84 V.

At this moment it looks either like too nasty output voltage for the data board, or the board is bad itself. Will keep you informed.

ADD// data board is the cause, no voltage output when it is connected; to be precise, PSU runs for half a second and than probably goes into some protection mode (but it is completely silent)

[Behemot]

Re: Dead 19" LG Flatron

The riskier approach is to unsolder one end of J1 (circled in black). This will disable the inverter. If the power supply now works, the problem is in the inverter.

After this step the PSU does not run even withotu the data board. There is optocoupler between PSU and inverter part so I think it has some feedback from there making the PSU part go into safe mode when the inverter is not running.

Photo of that yellowed part is attached as well as the data board.