Screen Vignetting?

[equant]

My Powerbook 540 is experiencing vignetting on the screen, and I'm curious if there's a known cause/fix for this. At first, the problem isn't aparent, but as I use the machine it gets worse. The actuall vignetting is a inversion of the pixels.

 

[kissmyash933]

Actually, I think that's a known problem of either the Backlight or the Invertor board.

I had that same problem with an old powerbook of mine.

 

[tomlee59]

If you're referring to a progressive darkening that starts at the corners and works its way toward the center, I'm afraid that it's caused by contamination of the liquid crystal material by moisture. Evidently, imperfect seals at the corners allow moisture to creep in over time. There is no known fix (other than replacement).

 

[MrMacPlus]

both my PB 160 and 145b are experiencing similar things. The screen gets brighter and brighter until you can't see anything.

 

[JRL]

both my PB 160 and 145b are experiencing similar things. The screen gets brighter and brighter until you can't see anything.

That's a slider problem.

 

[tomlee59]

The most common source of the progressive brightening problem is a flaky connector cable. This problem was widespread in the 1xx 'book series. If the problem goes away when you flex or squeeze the frame of the display (try the left or right edge), that pretty much confirms the diagnosis.

The fix is easy. Disassemble the display portion, remove the flex cable, then reinsert it. Do this a couple of times, then test. Do not touch the exposed conductors (for the display's sake, not yours).

 

[JRL]

My second PB 160 has this problem too, but it occurs less often and when it does, it almost always stops when the desktop loads.