Acer lcd monitor p191w problem

agbakery

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Jun 17, 2011
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Hello, my acer p191pw initially turns on when the pc 1st boots up for 5 seconds then goes black. If I turn the power back on to the monitor, it comes on for 5 seconds then goes black. Replaced power cords and pc cable to no avail. Any thoughts?
 



I have the exact same problem. My guess is that it's in the connections associated with the backlights, and somewhere along the line, the circuitry is realizing things aren't right, and it's shutting itself off in an attempt to save itself. As a minor detail, when it's acting up this way (it doesn't, always) when first turned on, it only has one of the two backlights working properly, and this can be seen as a darkening over on one side of the screen. Just so you know, ok?

Anyhoo, since the thing is unusable (it invariably fails when I'm right in the middle of something important, and it can no longer be trusted), I figured I'd open it up, and that's when I discovered there's not really anything out there on the internet (or at least not anything I can find) by way of instructions to get inside the unforgivingly inscrutable plastic case it's Hermetically sealed within.

So about an hour ago, I decided to take a chance on it, figuring there's no harm done if I destroy it in the process, right?

And I took pictures, too.

Straightaway, you must remove the mounting bracket along with a single screw that serves to hold the actual monitor hardware itself inside of the rear plastic casing piece.
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Then you must remove the gray plastic trim pieces that run along both vertical edges of the monitor. These can be pried off, gently, VERY gently, with a fine-point straight-slot screwdriver. Start over one one side:
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Work your way along, using the shaft of the screwdriver to force the plastic latches to let go, but be CAREFUL not to break them, 'cause they'll want to do exactly that.
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Once the gray plastic trim pieces are off, you'll see a series of holes in the exposed part of the rear plastic casing piece. Some of the holes are rectangular in appearance, and single, while others are round and have a bit of a slot or notch in them that abuts the front plastic casing piece. There are three of them, although only two are visible in the photo.
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Insert a small straight-slot screwdriver blade into the slot or notch as shown in the photo.
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Then lift the screwdriver towards the front (the side you look at, where the screen is) until the plastic latches release, as shown in the photo.
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Do this with all three of these holes, being careful to keep the stupid front plastic casing piece from returning to its original position with a happy little snap as the latches re-engage.

Once these latches are clear, you may then use a somewhat larger straight-slot screwdriver to work along the opening and disengage the rest of the plastic latches.
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Once both sides are disengaged, you may then continue to work around with the larger screwdriver and get the top...
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...and the bottom.
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When the last latch is disengaged, the front plastic casing piece will fall off.
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Note the bit of broken plastic latch between the screwdriver and monitor. Don't say I didn't warn you, ok?

With the front plastic casing piece gone, the small printed circuit board with the control buttons on it is free to flop around in the breeze. Mind that, 'cause it's delicate and if you lay the monitor down on it awkwardly, the weight of the monitor, along with some nice leverage, will rip the wires loose. We don't want that, do we? I chose not to use the little connector to remove it in my case, because I wanted full functionality following disassembly, so as I could test things. Undo the connector and remove the button board if it bothers you to leave it dangling, ok?
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As of right now, there's nothing in the world holding the guts of the monitor inside of the rear plastic casing piece, so be careful. Carefully lay the whole schmutz face down (mind that button board!) on something that won't damage the business end of the monitor, and lift the rear plastic casing piece off of it. It comes right off. Nothing in the world to hold it in place at this point.

In the picture below, you can see how nice and neat the button board (white arrows) is laying, right where it's supposed to be laying, and you can also see the metal tape (black MIRV re-entry vehicles) that holds the guts of the monitor to the LCD screen. Please note, that there's nothing else holding those guts to that LCD screen, except for that tape. Well, there's some wires buried in there, but if you mishandle things after removing the tape, the wires will cheerfully rip right out and that will be the end of that. Mind where you're at, ok?
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Once piece of tape seems to do nothing more than hold the guts in place against the LCD screen, but the other piece(s) cover the wiring harness that goes from guts to screen. This tape is there for a reason, and isn't freely available at your local 7-Eleven, so be careful with it, 'cause you're gonna want to reuse it. But even when you're being careful, it will still want to tear. Work slow, work steady, work gently.
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The wiring harness is a dual affair, and each half is further doubled where it connects to the guts. The length of wires will tell you which one is which in that regards, but at the connector end of things both connectors are identical, so I suggest using a fine-point Sharpie to place a couple of small match marks on each half one of the connectors, so as you'll know which one goes where, later on after you've forgotten.
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Should you decide to remove the wires, be mindful about the weency little latches on the connectors. Pry them up with the small screwdriver as you GENTLY rock the wired end of the connector loose and pull it out from within its mating half. This is a wonderful place to rip a wire out, so take your time, go slow, sing yourself a song, whatever it takes. Just don't go snatching at it, ok?
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At this point, it would appear as if the guts are now completely free of the LCD screen. They're not. Be careful. There's still time yet to wreck the train, so proceed with caution.
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Underneath, hidden from view, there's a ribbon cable with more of that metal tape on it. So if you want to take the guts off, that tape has to be gently removed and the little connector disconnected.
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And that's as far as I've gone with it so far.

Right now the stupid thing is sitting over on the test table, working perfectly, refusing to so much as flicker.

Ah well, perhaps it was the little connectors, and my disconnecting them and reconnecting them in some way made things all better. But I kind of doubt it.

Regardless, the worst of the job is done, and now everybody else will know how to get inside one of these things. From there, it's pretty straightforward electrical work, and anybody who doesn't know how that works needs to stay the hell out of one of these things, or otherwise they'll take a nasty jolt of juice at some point, and who needs that?
 



If you still have that monitor ill gladly buy it off you for spare parts for mine sniperhunter1984@aol.com if interested or if you want it can be fixed by replacing the power supply in it the capacitors in it are not the best you can buy a new board for it or buy new upgraded capacitors and solder them on your self after removing the old ones hope this helps