iMAC G4 pink screen of death!

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iMAC G4 pink screen of death!

There have been many posts regarding monitor failures on G4 (flat pannel) iMacs. We experienced two rounds of it. At first, I thought I corrected it, but it appears that the "solution" was just an intermittent return to normal operation.

There are two reported problems: The first is a complete failure of the backlight, which renders the screen black, but readable by flashlight! The second is a change in the monitor colors.

Our problem is the latter - when booted normally, the screen is a pink hue. Blueish tints seem to be present, but I wonder if this means that green has completely failed in the monitor? I've done some trouble-shooting. The bug does not appear to be software related. When booting in a text mode (i.e. single user) the screen is red instead of black and the text is white. When booting into open firmware the text is red on white.

An external monitor works fine. Does this suggest that it is not the video card or main logic board? It is either in the monitor or something between the monitor and CPU. I inspected the monitor connections - they seem to be seated fine. I have not opened the CPU to check connections there.

I like Apple products when they work. But there are three problems here: a defective product, a limited supplier of parts, and poor technical service on the part of Apple. I can't afford to "fix" a computer for $1000 with a main logic board replacement when it cost me $1200 to begin with!

Mac OS X (10.4.2)

Posted on Dec 25, 2005 4:00 AM

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Answer 1

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Adam Coates

Level 4

1,855 points

Dec 26, 2005 2:59 PM in response to efurst

My experience of coloured hues on displays have always been solved by finding the loose connector.

My projector often goes yellow when the SCART lead gets nudged and my old Performa 6400 went pink if the monitor power cable was loose.

I suggest you pop your machine to a local AASP and ask them to diagnoise the issue. (My local one charge about £35). They may well re-seat the connectors for no more than that cost.

iMac Logic boards.

Merry Christmas

mrtotes

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Answer 2

efurst Author

Level 1

0 points

Dec 30, 2005 9:46 AM in response to efurst

Screen connector indeed.

Here's the run-down on my solution:

1. Open firmware, etc. booted with red on white text, suggesting the problem was hardware, not software.

2. External monitor worked suggesting it wasn't the main logic board (and presumably the video card?)

3. Back light was on, so it wasn't the inverter.

4. Everything functioned normally except that GREEN seemed to be missing.

Solution: I found that giggling the monitor connector while the computer was on fixed the color problem. Below is a step-by-step.

To remove the monitor, there are nine hex nuts on the white frame. These need to be removed. I found that laying the computer down with the montor screen facing up was the best way to work. After removing the screws, the monitor can be lifted out by the white frame where it meets the clear part of the monitor case. A dry run with the power off was helpful.

There are two cables coming from the LCD connection to the monitor arm. To give myself more room, I disconnected the microphone and power indicator light wires (bottom smallest connectors, labeled.) The four wires from the inverter (pink and white) were long enough for a little working room. The monitor cables are taped down at the connector to the monitor (an adhesive material square and orange tape holding it together.) Gently peeling the tape, you have access to the monitor connector. Disconnecting completely yields a white screen. I giggled it around a bit and the colors reverted to normal. I taped back together while monitoring the colors to make sure the connector stayed seated, and bolted everything back together.

So far so good.

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Answer 3

Dec 30, 2005 2:23 PM in response to efurst

Good work!

mrtotes

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Answer 4

Feb 15, 2006 6:58 AM in response to efurst

Yesterday my iMac G4 took a powder with the "pink screen of death" when I woke it up from sleeping. At first I thought it was odd that it would have a pink hue on Valentines Day, but my iMac G5 was fine. I have 10.4.4 and Sophos AV installed on both. I never move the computer (ever) and I have it in an area with good air flow.

So I look it up on the support to no avail. I found some links in the outside world to forum posts that are now missing (deleted). So I just decided to view the posts one-by-one on here and there has to be several dozen different threads started.

My machine is less than three years old, but I didn't RTFD on activating the warranty so therefore I am SOL on getting it fixed through Apple. I talked to an old workmate who is the IT Dir for a school running 500+ iMac G4 (and G5). He told me that he has had close to a dozen failures in the past two months. His Apple support has been poor, in his opinion, but he was able to get them fixed under warranty. He did however, tell me how to fix it, and pointed me to some web articles.

So I tried the fixes on the monitor cable and it appears to have worked for now. The video cable didn't look loose to begin with but pushing it down harder seemed to do the trick. Buying the Heat Sink Compound, an important step, was easy as most Radio Shacks carry it for under $3USD. I doubt that most people would be able to pull this repair off themselves though.

My point is that this does seem to be a widespread issue and I can only hope that Apple does the right thing. I know they have extended repairs past warranty expirations in the past and think they should consider doing that here to save people the hassle of doing it themselves or having some repair shop botch it for $$$.

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