Sceptre X22WG-1080p monitor not staying backlit, Please Help!

[PlainBill]

Re: Sceptre X22WG-1080p monitor not staying backlit, Please Help!

I have the same exact problem, the monitor will be on and it will go completely black , when I power cycle it will come on for a little bit maybe a minute or two, then go black again.

Sometimes the monitor will work for weeks with no problem, the only solution is to turn it off and let rest for a while.

If the inverter is bad is there any solution? Where could I find a new inverter power supply for this unit.

Thanks

Chris

If you have proper test equipment it should be possible to repair this one. Certainly if the backlights stay on for a minute of two, troubleshooting it will be relatively easy.

Do you have a DMM? If so, the tests in post 5 are a good starting point.

PlainBill

[coulthrust]

Re: Sceptre X22WG-1080p monitor not staying backlit, Please Help!

I have the same exact problem, the monitor will be on and it will go completely black , when I power cycle it will come on for a little bit maybe a minute or two, then go black again.

Sometimes the monitor will work for weeks with no problem, the only solution is to turn it off and let rest for a while.

If the inverter is bad is there any solution? Where could I find a new inverter power supply for this unit.

Thanks

Chris

[SupeR]

Re: Sceptre X22WG-1080p monitor not staying backlit, Please Help!

Ok thanks!! You have been really helpful! I'm going back to school, and the only time i get to do this stuff is durring breaks when im home. But i will pick up a DDM and do that when i get the chance next, hopefully soon! Thanks again!! Maybe you'll hear again from me in a month or two.

Ryan

[PlainBill]

Re: Sceptre X22WG-1080p monitor not staying backlit, Please Help!

Ah shoot, I don't believe i have anything to measure that with...

Well, that sucks. I see five options at this point:

1. Borrow a DMM (or have a friend check it for you).

2. Buy a DMM. Harbor Freight Tools sells a rather nice one for $25. Fluke sells VERY nice ones for somewhat more.

3. Give it to someone who has the capability of repairing it.

4. Send it to the landfill.

5. Try these tests. This MIGHT damage the inverter. For simplicity we will label the CCFL wires from the inverter as A, B, C, D. The wires to the CCFLs will be labeled 1, 2, 3, 4. Normally A connects to 1, B to 2, C to 3, D to 4. We will describe this as A1, B2, C3, D4. Got it?

Disconnect B2, C3, D4. Now the A output is the only one connected to a CCFL. Position the panel so you can see the face of it. Plug the monitor in and cycle the power button (press it twice, pausing a second or two between presses). Does the screen light up briefly? If yes, estimate it's brightness, then disconnect A1 and hook up the B2. Cycle the power button. If it lights up, is the brightness about the same as A1? Repeat this for the remaining CCFLs. If all worked at the same brightness you probably have a problem in the inverter; specifically in the monitoring circuit.

If a lamp did not light, or was dimmer, you have to figure out if the problem was the CCFL or the inverter. As an example, we will say that B2 was much dimmer. Now hook B to 1 and cycle the power button. Is the CCFL now at full brightness? Try hooking A to 2 and cycling the power button. Is it now at full brightness?

If a CCFL (1, 2, 3, 4) will not light at full brightness no matter which output it is connected to, there is a problem with that CCFL or it's wiring. If an output (A, B, C, or D) will not light a CCFL at full brightness you have either a bad solder joint or a bad transformer.

PlainBill

[SupeR]

Re: Sceptre X22WG-1080p monitor not staying backlit, Please Help!

Ah shoot, I don't believe i have anything to measure that with...

[PlainBill]

Re: Sceptre X22WG-1080p monitor not staying backlit, Please Help!

Should I replace the big Taicon cap and the small green one next to it?

Neither is the cause of the problem you are having. I would recommend replacing the small electrolytic cap if you get this working. That cap performs a very important function and if it fails your monitor won't work.

I've marked up the picture of the bottom. Measure the resistance from point A to B; C to D; E to F; and G to H.

The large IC on the bottom appears to be a BD9883AF; please verify that.

If all transformers read the same I will ne a better picture of the bottom; especially the traces below the transformers.

PlainBill

[SupeR]

Re: Sceptre X22WG-1080p monitor not staying backlit, Please Help!

Should I replace the big Taicon cap and the small green one next to it?

[SupeR]

Re: Sceptre X22WG-1080p monitor not staying backlit, Please Help!

Bottom of Inverter board
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Top
[/IMG]

[PlainBill]

Re: Sceptre X22WG-1080p monitor not staying backlit, Please Help!

Around a second after pressing the power button the monitor displays the source perfectly then the backlight turns off. I put a flashlight up to the monitor and see that the picture is fine and still there, just not lit up. I have replaced the 8 (main) capacitors 470uf 35v and the same thing happens. The only ones that are left that could possibly be replaced are a small and large capacitor. Should i just toss the monitor since replacing the common ones didn't work

Well, if you WANT to, pack it carefully and 'toss' it my way. However an approach that might be more rewarding for you would be to take pictures of the top and bottom of the power supply board. You have what is referred to as the 'two seconds to black' problem. Solving it is more difficult that just tossing caps at it, but it is fixable.

PlainBill

[SupeR]

Around a second after pressing the power button the monitor displays the source perfectly then the backlight turns off. I put a flashlight up to the monitor and see that the picture is fine and still there, just not lit up. I have replaced the 8 (main) capacitors 470uf 35v and the same thing happens. The only ones that are left that could possibly be replaced are a small and large capacitor. Should i just toss the monitor since replacing the common ones didn't work