Samsung LN-T4032H

[shorteddiode]

It works for awhile then the backlights go off but the sound stays on. If it is unplugged it will work for awhile then the backlights will go off agin. The longer it is unplugged the longer it will work. I have replace both inverter boards, but didn't help. When I lose thge picture I have 5.28 volts at the fuse of the t-con, 12 volts to the top plug og the inverter. I also repaced the caps with the red X in the photos on the power board. The first picture of the scope is when the picture is working and the second on is when the picture goes off.

[tom66]

Re: Samsung LN-T4032H

Resolder ALL the joints under the transistors on the heatsinks. Samsung TVs are well known for cold solder joints.

[shorteddiode]

Re: Samsung LN-T4032H

Thanks I'll give that a try, any other ideas?

[tom66]

Re: Samsung LN-T4032H

Possibly a bad CCFL.

[shorteddiode]

Re: Samsung LN-T4032H

Yeh I thought of that, but how do I test for it. If I unplug a light at the inverter board the tv will not turn on. I do not get any dark areas before the picture quits

[tom66]

Re: Samsung LN-T4032H

You would have to take the panel apart unfortunately to see if there's a bad bulb, it's often not visible on the screen.

[shorteddiode]

Re: Samsung LN-T4032H

Ya think the buld resistance goes up as it get warm? Cazn I test by finding a way to power one bulb at a time? Or is there a resistance test?

[tom66]

Re: Samsung LN-T4032H

Ya think the buld resistance goes up as it get warm? Cazn I test by finding a way to power one bulb at a time? Or is there a resistance test?

No way to test by resistance as far as I'm aware.