Samsung LE37M86 - Flickering green artifacts on screen

[Jooo]

Hi, I'm currently repairing this Samsung 37" LCD, which has flickering artifacts on screen. The PSU had several bad caps, so maybe the faulty PSU has broken something else, but what?
I tried freeze spraying the mainboard and TCON with no change at all
Any ideas?

[tom66]

Re: Samsung LE37M86 - Flickering green artifacts on screen

Try switching from the picture mode in the user settings menu.
If this fixes it (temporarily) you will have to perform an EEPROM reset.

[Jooo]

Re: Samsung LE37M86 - Flickering green artifacts on screen

Try switching from the picture mode in the user settings menu.
If this fixes it (temporarily) you will have to perform an EEPROM reset.

That did not sadly fix it even temporarily, but it made the artifacts different color, when in movie mode they are red, and in cold picture mode they are black.

[tom66]

Re: Samsung LE37M86 - Flickering green artifacts on screen

Ok, but since it changed, it indicates EEPROM reset needs to be done, do you know how to do this?

[Jooo]

Re: Samsung LE37M86 - Flickering green artifacts on screen

Ok, but since it changed, it indicates EEPROM reset needs to be done, do you know how to do this?

Haven't done it before, but quick research showed me that I need to:

- Bridge pins 5 & 6 on the EEPROM chip,
- Plug the TV in and wait untill standby light comes on,
- Wait couple of seconds, do not turn the TV on,
- unplug the tv, remove the bridge,
- and then turn the TV on normally. Correct?

[Jooo]

Re: Samsung LE37M86 - Flickering green artifacts on screen

Ok, but since it changed, it indicates EEPROM reset needs to be done, do you know how to do this?

I tried it like you had described here (This TV has the same mainboard)
Unfortunately this did not help. When the jumper is connected, the set will not even try to turn on. I did the reset in the service menu too.

[Jooo]

Re: Samsung LE37M86 - Flickering green artifacts on screen

Any ideas?

[Jahson]

Re: Samsung LE37M86 - Flickering green artifacts on screen

That's the same mainboard im replacing on a Sammy, LE40M87BDX, those green lines was the same effect I got when heated a certain part of the mainboard.

It was causing the set to cut out & resetting. Cant give a accurate part location on the board at the moment, I have a look later.

https://www.badcaps.net/forum/attach...3&d=1415827767

That chip in the center slightly to the right, inline with the writing Tulip 40 dtv. check what components on the opposite side of the board in same location also.

[Jooo]

Re: Samsung LE37M86 - Flickering green artifacts on screen

Heating or cooling that chip didn't do anything...
I also tried to replace the EEPROM chip, but the problem is still there.
Might have to replace the mainboard as well, sadly there didn't seem to be any fairly priced ones available... or could it be the TCON?

[saddle_au]

Re: Samsung LE37M86 - Flickering green artifacts on screen

Looking at that, I would check out the TCON on-board regulator and the multiple voltage generator. I would suspect a large ripple voltage is in there somewhere.

[Agent24]

Re: Samsung LE37M86 - Flickering green artifacts on screen

Have you verified all voltage rails and secondary regulators are in spec and stable?