LN-T3232H Backlight ON, No picture

[alfredomfr1]

Let me explain in my poor English.
TV turn ON, can see the backlight ON from the back of the TV, Screen remain black, I pressed the menu button, can't see nothing on screen but if you press the screen a little bit, you can see the image in the place that you are pressing
Thanks in advance for the help

[budm]

Re: LN-T3232H Backlight ON, No picture

You should check the fuse and the voltage on both ends of the fuse on the T-CON board.
https://www.badcaps.net/forum/showthread.php?t=39740

[alfredomfr1]

Re: LN-T3232H Backlight ON, No picture

Fuse OK, Voltage: 5v

[alfredomfr1]

Re: LN-T3232H Backlight ON, No picture

Any help, please

[selldoor]

Re: LN-T3232H Backlight ON, No picture

Test the gama voltages on testpoints gm1 to gm4 are on the right side of the tcon and gm5 to gm14 on the left.

Are you sure the backlights remain lit?

[alfredomfr1]

Re: LN-T3232H Backlight ON, No picture

gm1: 1.39v
gm4: 1v
gm5: 0.95v
gm14: 0v
Yes, backlights remain lit (I can see the white light from the back)

[Andrew F. Ali]

Re: LN-T3232H Backlight ON, No picture

Check the Main Bd for dry/cold solder joints. Reflow areas that look suspicious.

[alfredomfr1]

Re: LN-T3232H Backlight ON, No picture

what about the gm1,4,5 and 14 values?

[Andrew F. Ali]

Re: LN-T3232H Backlight ON, No picture

OK. I think SELLDOOR means: GM1: 1.39V, GM2: x.xxV, GM3: x.xxV, GM4: 1.0V,
GM5: 0.95V, GM6: x.xxV to GM14: 0.0V. Looking to see if the voltages increase or decrease in a regular manner or if they are random to determine if the T_CON board is faulty as Vcc: 5V may be OK but other proirity voltages like Vgon, etc may be missing.

[alfredomfr1]

Re: LN-T3232H Backlight ON, No picture

gm1 to gm14 decrease regularly. I found a Vgl: 5.7v but can't found Vgon

[selldoor]

Re: LN-T3232H Backlight ON, No picture

all the gamma progressions I have seen go up to around 12v??? suggest you research this

[budm]

Re: LN-T3232H Backlight ON, No picture

The board has two 3-pin Voltage regulator ICs, what Voltage do you get on all 3 pins?

[alfredomfr1]

Re: LN-T3232H Backlight ON, No picture

the 50117 ok,
UP4 UP5: Left: 0v, Center: 2.55v, Right: 4.76v
UP2 UP3: Left: 0v, Center: 3.35v, Right: 5.22v

[budm]

Re: LN-T3232H Backlight ON, No picture

They are OK, at this point I would try another T-CON board, P/N from the barcode: 35-D021291. It is not cheap.
http://www.shopjimmy.com/catalogsear.../?q=35-D021291
SJ also has the repair kit so it looks like common failure board.

[alfredomfr1]

Re: LN-T3232H Backlight ON, No picture

I just want to clarify that I can see the image, the thing is that is like there is not backlight but it is, I see the white light when I look from the back of the panel

[budm]

Re: LN-T3232H Backlight ON, No picture

Can I see the screen shot to see what the pictures look like? it sounds like you have washed out or Dark pictures which can be due the AS15 Gamma IC U6.

[alfredomfr1]

Re: LN-T3232H Backlight ON, No picture

I ordered the repair kit from shopjimmy, will be back soon.
Thanks for the help.

[alfredomfr1]

Re: LN-T3232H Backlight ON, No picture

IC arrived today, replaced, still same problem

[Shinju]

Re: LN-T3232H Backlight ON, No picture

I had a "Samsung" T-con brand if you will, on a 2 year newer LCD that did the exact same failure. I believe the ram dacs have failed or got shorted, when I pressed on the screen I could see several vertical lines very very faintly on the display.

I bought a used t-con off ebay and the panel fired right up, only to find a stupid tab bond issue "victim of cleaner" that probably cause the damage to the T-con in the first place. lots of electrolysis on one tab.

These "Samsung" brand T-cons are pretty hard to trouble shoot. I know AUO optronitcs gets bagged on but at least with those we know what to expect and 9/10 times its always the AS-15 chip.