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PowerBook G4 display decay: Uneven illumination; Pink, red hues after extended use

PowerBook G4 display decay: Uneven illumination; Pink, red hues after extended use

Continuing our investigation of PowerBook screen issues:

Uneven illumination The screen illumination inconsistency issue (some parts of the display brighter than others) which was covered in our PowerBook G4 special report last November, is continuing to receive increased attention as users send their units in for repair, and receive replacements that exhibit the same problem after only a few weeks.

To recap, most reports indicate that one side of the screen, or the corners of the screen, gradually become dimmer than the rest of the display area. The problem appears to get worse with time, as some users can - at first - only notice the dimness with a solid, light color (such as the Mac OS X startup screen).

One MacFixIt reader had a particularly bad experience with the illumination problem:

"I've had 5 repairs performed between my original 15" Aluminum PowerBook and the replacement I received. Right now, my second replacement is on its way from Apple... all because of this defect, Uneven Illumination.

"I've tracked at least 93 individuals at Apple's Discussions who reported this defect afflicting their systems. Over 40% of them have had at least one recurrence after a 'repair.'

Pictures of the problem Several readers have posted pictures of the screen illumination issue, with similar display appearance in most cases:

The above reader, "Darkside," has posted a gallery, of shots depicting the problem, as has Jim Little.

Pink, red hues after extended use Another, apparently separate problem for which we are seeking confirmation, involves heavy-use PowerBook screens eventually developing pink or reddish hues:

MacFixIt reader Ron Stark writes "Recently I began to notice the screen of my 15" PB G-4 would be pink or almost red in color when I opened the cover bringing it back to life after its sleep between house and office. The red color would yield to a pink tone and as the machine spun up the pink would give way to a pinky white screen. The matter got worse not better over time. How long a time? Well, once I noticed the pink tone it began to get worse over a mere couple of weeks.

"The machine is little more than 18 months old and is covered under the very necessary AppleCare plan. Upon discussing the problem with a technician at the Apple Store the first thing he asked was, 'does your machine remain on for a great amount of time?' I indeed said it does as its almost always plugged in and there would be no reason to dim the display as its not like a CRT, right? 'Nope, wrong,' the techie said. 'You see, there are two cold cathode tubes at the top and bottom of the screen that weaken with use and they turn pink in time. The display needs to be replaced!'

"Moral of the story; power down the display when not in use even though its plugged in. The Powerbook, and iBook screens are vulnerable."


  • PowerBook G4 special repor...
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  • Jim Little
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