Samsung LCD TV LN40B530P7N Distorted Color Picture

[Glitcher]

I have a 40" Samsung Model: LN40B530P7N
The color of the picture seems extra contrasted or distorted like. It would actually look kind of normal only when cartoons are playing. It affects all the inputs.

If I'm seeing it right, it seems to be getting worst from when I turn on the Tv from cold and leave it on for awhile. A thermal issue? Should I check the Tcon or the Mainboard first?

[tom66]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Select a source which shows the issue.

Turn TV off, leave it in standby.

Press, on remote, Mute, 1, 8, 2, Power in quick succession.

TV turns on. Service menu appears.

Browse the menu. Look for options marked LVDS format. If you need help, take a picture of the service menu. If you find an LVDS format option, change the value using the remote to one of the other values until the picture comes back normal.

[Glitcher]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Got to the service menu, I found an option "LVDS Format" There was only 2 settings for it, JEIDA and VESA. It is default set on JEIDA, but changing it to VESA seem to make it worse.

[tom66]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

OK, set it back to the original, then look under Panel Enter Key. What appears when you select that?

[Glitcher]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

I just tried a factory reset but no luck.. Clicking on Panel Enter key, it just says panel enter key on the screen but I'm pressing the buttons and nothings happening after.

[tom66]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Nothing happens when you press enter, or left/right?
Any "Panel Option" available?
See this video.
https://www.youtube.com/watch?v=c-aXKCTiU6I

[Glitcher]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Yep, nothing happens pressing left/right, enter, buttons, etc. Heres a couple more options I found.

The picture actually looks like its becoming negative. When I first turned it on I thought to my self that the problem wasn't that bad, but now its really obvious, so I think it has been getting worse.

[tom66]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Go down to PANEL TYPE and try selecting it.
There is a chance it is GAMMA IC problem.

[Glitcher]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Just tried selected it, and I can't do anything with it either.

[tom66]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Very strange, can you go into TEST PATTERN and see what each test pattern looks like?

[Glitcher]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

All the solid colors seem to be good (black blue red, etc) until the later colors.

[tom66]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Personally I still think main board but can you take a picture of the T-con? May have common AS15G IC on it which fails and can cause a similar fault.

[Glitcher]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Here you go, The T-con does have a AS15-F chip. Trying to find my compressed air spray.

[tom66]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

See the points marked VGMA1, VGMA2 ... VGMA20?

Use your DMM to measure each. Put your black probe on the chassis of the TV and red on each pad from 1 to 20. DC20V range. See what readings you get, post them here.

[Glitcher]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Heres all the measurements I got from pads 1-20. (In volts)

1: 15.46
2: 15.17
3: 15.04
4: 12.82
5: 11.9
6: 10.82
7: 10.17
8: 9.86
9: 8.51
10: 8.35
11: 7.90
12: 7.09
13: 6.86
14: 7.33
15: 11.44
16: 9.29
17: 4.66
18: 3.59
19: 2.65
20: 0.61

[tom66]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Definitely bad then. The voltages should decrease or increase one way only. That spike around 14-17 is probably the cause of the fault. Replacing the IC or the T-con should fix the fault. I retract my original conclusion of main board; I've just seen so many main board solarised picture faults recently I went straight for that.

[tom66]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Just noticed there are pads 21 and 22. Could you test those too (for future reference for others.)

[Glitcher]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Pads 21 and 22

21: 0.50V
22: 0.25V

Been searching for the Tcon around but can't seem to find it anywhere. There's only one result for it on ebay but its about $110.

Do you know a good source to purchase the IC?

[tom66]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

Thanks for those.
What is the full part # on the AS15 chip?

[Glitcher]

Re: Samsung LCD TV LN40B530P7N Distorted Color Picture

As15-f
0838cg
b8601677