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NEC LCD1935NXM quick picture then black screen

Hi Everyone,

I'm hoping you can help me with an issue I'm having with my NEC flat panel monitor model LCD1935NXM. This monitor was purchased a few years ago and I recently started having trouble with it. The screen shows no picture when connected to my computer. If I turn it off and on, I get a quick (1 second) picture then solid black screen. I have tried setting this up with VGA and DVI cables to no avail. I also do not believe this is a setting issue as I have tried the monitor on several computers adjusting the display settings on all of them.

Does this monitor have a chance or is it destined for the landfill? I paid a lot of money for this and I would be saddened to see it go. Anyone have any idea what could be causing this ? Thank you in advance for your help.

Reply to
Jstein
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Does the power LED stay lit when the picture goes away? You could have a power shut down if it flashes or goes out. Unless you have electronic repair skills, it is unlikely that repairing it is worth the cost.

The only practical repairs I have seen are to the power supply. Filter capacitors often show signs of failure by bulging, but some do not. Other failures (particularly in the display) are often difficult to diagnose and obtain parts in order to repair them.

Reply to
Ken

(sigh) Would have been nice if you had done some research (there's this website called *Google*...) before posting.

*Knowing* what *should* be on the screen, shine a flashlight obliquely (so the reflection doesn't come straight back at you) *into* the screen. If you can see the image that you *expect* to be there, then your backlight(s) are not operating (but the panel itself *is*).

Then, use Google to see why that might be the case and what you can likely *do* about it (assuming you have the necessary skillset).

Reply to
D Yuniskis

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I was able to shine a flashlight on the screen this weekend and their is in fact a picture so it would appear this is a back lighting issue. Because the screen turns on at full brightness for a split second, would this imply that the back light has completely failed (and needs to be replaced) or could there potentially be another issue affecting this ie power supply, component failure etc?

Reply to
Jstein

The fact that the backlight powers up at full brightness and then shuts down suggests pretty strongly that you have a controlled shutdown by the inverter controller. Two likey causes are (a) a tube failure causing imbalance and (b) some non-tube-related fault in the inverter drive circuitry. My bet is on (b).

Reply to
who where

Look for bad caps on the primary to the inverter.

Reply to
D Yuniskis

I was able to dive into this project the other night and did determine that one of the surface mount fuses is open. I have uploaded an image of the board here:

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The fuse that is open is labeled F2. The other surface mount fuse is labeled F3 and appears to be fine. Can this fuse be replaced by an AGC fuse ? Is it likely that this fuse failed on its own or there is another underlying issue with the inverter board? My fear is that a new fuse will fail immediately after the unit is powered up. Any suggestions are greatly appreciated.

Reply to
Jstein

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