PowerSpec 30" LCD TV (v30dmbt)

[troxel]

I got this TV, and replaced a few parts in the power supply, and now TV powers up. However, after so many seconds the TV will go black. I can hear the sound and it I switch source I can see the screen, but will go back to black in AV setting. The time will vary before it goes dark. Sometimes it was a couple of minutes other times a couple seconds.

The TV is missing the TV tuner. Would this cause this problem, or what else should I check.

Thanks!

[tom66]

Re: PowerSpec 30" LCD TV (v30dmbt)

When it goes dark does the backlight go out or stay on?
Is sound affected?

[troxel]

Re: PowerSpec 30" LCD TV (v30dmbt)

How do you tell if the backlight is on? Would it glow? I would assume the back light is not on, because there is no glow, however the sound is good. I can still hear the movie playing. The TV will go black instantly.

I turned it off for a bit, and after about 5 minutes starting doing the same thing.

[tom66]

Re: PowerSpec 30" LCD TV (v30dmbt)

You will easily be able to see in a dark room. Also most LCD panels have holes in the rear which will glow when the backlight is working.

[troxel]

Re: PowerSpec 30" LCD TV (v30dmbt)

TV will work for a bit then suddenly goes to black. The audio is still playing and the led stays green on the front. There appears to be no backlight as there isn't any glow on the screen.

What would be the next step in troubleshooting this tv?

Thanks again!

[Caleb]

Re: PowerSpec 30" LCD TV (v30dmbt)

In your first post you said it only does it in av mode, so if you switch to your cable input you can see the screen fine? Ive had several tvs with poorly soldered video connectors that would act in a similar manner if you wiggle the yellow one does it come back on? If so it isnt the backlight but a dry joint that can most likely be resoldered easily once you get the set open.

[troxel]

Re: PowerSpec 30" LCD TV (v30dmbt)

I tried an s-cable and got the same results. I don't have a tv tuner with the television, so I was wondering if that was part of the problem, too.

With the s-cable or a/v cable I could watch my dvd for a while, and then it would go to black.

[Caleb]

Re: PowerSpec 30" LCD TV (v30dmbt)

If it does it in multiple modes it is most likely the back light circuit has an intermittent fault and is shutting itself down. If you can find a replacement board you can swap them out. I had my sons tv do the same thing last weekend and I was able to isolate the shorted inverter transformer with a ring tester and just remove it from the board to get the set back up (minus a backlight) until I can source a replacement transformer. If you have a ring tester you can try testing the inverter transformers see if they are bad. Other than that you will need a new inverter board.