Samsung 37" t370hw02 - distorted picture.

[Hamie]

Was up at the local recycling center yesterday dumping some smashed panels and came across this little number.
In great condition with remote and power cable! Lucky day.

Anyway, it has a distorted picture as below.



Can someone tell me if it need a new logic or t-con.

Things tried already.

Service menu: various options tried- (info, menu, mute, power on) no real change to picture quality.

Wiggling lvds cable: goes dark then light.

Removing left tcon ribbon - left side back, no change right.
Removing right tcon ribbon - right side black, left side slightly more red.

Would I be correct in thinking the tcon is ok, and it's just a dodgy signal created by the logic board?

Don't have a problem replacing either board but want to make sure I get the right one.

Thanks

[tom66]

Re: Samsung 37" t370hw02 - distorted picture.

AS15 gamma fault on T-con board I'll guess. Picture of the T-con board please?

[Hamie]

Re: Samsung 37" t370hw02 - distorted picture.

AS15 gamma fault on T-con board I'll guess. Picture of the T-con board please?

Hello tom, thanks for your help.

Here's the tcon.

[tom66]

Re: Samsung 37" t370hw02 - distorted picture.

OK, do you see the block of test points next to the right hand ribbon marked VGAMA1, VGAMA2, etc.? Check each, noting down the voltage for each VGAMA#.

[budm]

Re: Samsung 37" t370hw02 - distorted picture.

Another one with bad AS15:
https://www.badcaps.net/forum/showth...hlight=LN37%2A

[Hamie]

Re: Samsung 37" t370hw02 - distorted picture.

Cheers guys readings are.

1. 15.45
2. 15.42
3. 15.41
4. 15.9
5. 13.7
6. 10.66
7. 12.73
8. 13.74
9. 8.89
10. 7.77
11. 7.78
12. 14.75
13. 14.60
14. 14.63
15. 14.69
16. 13.80
17. 12.6
18. 9.83
19. 11.80
20. 12.83
21. 14.02
22. 14.24

[Hamie]

Re: Samsung 37" t370hw02 - distorted picture.

ok so going by toms spreadsheet it has failed miserably.
im going to just remove the chip and replace it, i take its the small square one covered by the pad..... hope i get it the right way round!

[Shinju]

Re: Samsung 37" t370hw02 - distorted picture.

Same panel I got and same failure! What AS-15 chip do you have? AS-15 G,F ect

[Hamie]

Re: Samsung 37" t370hw02 - distorted picture.

hello, unfortunately i cant read it! it had a pad stuck on it and the writting has gone.

[tom66]

Re: Samsung 37" t370hw02 - distorted picture.

You can use any AS15 to replace any AS15. And I bet it is AS15 as we have not seen this with other gamma ICs.
I used AS15-F to replace AS15-U for example.

[Hamie]

Re: Samsung 37" t370hw02 - distorted picture.

You can use any AS15 to replace any AS15. And I bet it is AS15 as we have not seen this with other gamma ICs.
I used AS15-F to replace AS15-U for example.

You were right about the chip.
Ok so I heat gunned off the old chip but unfortunately it took a pad with it.
Instead of wasting more time I ordered a new tcon from eBay (yeah I know.)

The new tcon arrived and the picture came back!
But now the picture slowly fades away after 30 seconds until the screen is completely black! The back light etc is still on.

I'm guessing I've bought a faulty tcon board again as the previous gamma fault picture didn't fade, what tests can i do on the new tcon to confirm if it's faulty?

Thanks

[sordids999]

Re: Samsung 37" t370hw02 - distorted picture.

OK, do you see the block of test points next to the right hand ribbon marked VGAMA1, VGAMA2, etc.? Check each, noting down the voltage for each VGAMA#.

The same tests tom posted before

[Hamie]

Re: Samsung 37" t370hw02 - distorted picture.

yip its faulty.

VCOM- 6.3
AVDD- 15.67
VGH- 27.23
VGL- 6.29

1 7.61 N/A N/A N/A
2 7.61 7.61 0 N/A
3 7.61 7.61 0 Pass
4 7.66 7.61 0.05 Fail
5 7.68 7.66 0.02 Pass
6 7.7 7.68 0.02 Pass
7 7.7 7.7 0 Fail
8 7.7 7.7 0 Pass
9 7.74 7.7 0.04 Fail
10 7.75 7.74 0.01 Pass
11 7.75 7.75 0 Fail
12 7.75 7.75 0 Pass
13 6.584 7.75 -1.166 Fail
14 6.581 6.584 -0.003 Pass
15 6.577 6.581 -0.004 Pass
16 6.434 6.577 -0.143 Pass
17 6.409 6.434 -0.025 Pass
18 6.36 6.409 -0.049 Pass
19 6.287 6.36 -0.073 Pass
20 5.995 6.287 -0.292 Pass
21 5.99 5.995 -0.005 Pass
22 5.92 5.99 -0.07 Pass

[Prchallenger]

Re: Samsung 37" t370hw02 - distorted picture.

Hey guys, I'm having a similar problem with the same board. It started with the same solarization and upon replacing the tcon I've got the same dark screen but now my old tcon gives just the dark screen as well. The cables seem intact and if i wiggle them, I get momentary vertical lines that then fade to black.
Any advice?
Thanks, Nick.
PS I wasnt sure if i should post this here or in a new thread, i can repost if I need to.

[Adam4791]

Re: Samsung 37" t370hw02 - distorted picture.

OK, do you see the block of test points next to the right hand ribbon marked VGAMA1, VGAMA2, etc.? Check each, noting down the voltage for each VGAMA#.

Hello. Tell me please, what voltages should be at the control points of the t-con T370HW02 BC?

[ducky29]

Re: Samsung 37" t370hw02 - distorted picture.

Check carefully with your finger if as chip gets hot.

[tom66]

Re: Samsung 37" t370hw02 - distorted picture.

Hello. Tell me please, what voltages should be at the control points of the t-con T370HW02 BC?

Just record all the voltages and tell us what you get.