Q: ibook g4 display is blinking, FIX?  

Have you tried resetting the PMU? The PMU is responsible for the backlight function, so if the display is blinking on and off, resetting the PMU may help.

Is the display blinking both when running from the battery and when running while plugged into the charging adapter?

If it just happens while running from the battery, then the battery could be the issue here, too.

Otherwise, there may be an intermittent cable issue with one or more of the display cables. Sometimes the various cables get pinched in the hinge, causing intermittent display issues. If adjusting the angle of the display corrects the problem, suspect a pinched cable.

Is that a blink physically where the screen goes on and off or a flicker of dimmer/brighter back light?

If it's physically going on and off for a second then it sounds to me like a power issue with the adapter or battery(as described by Ronda) or a video cable issue.

If it's where the screen becomes dimmer for a second and then brighter, it could indicate a problem with the inverter board.

If it where the screen graphics become distort (Like an old TV being tuned in) then that could well indicate the first signs of a over heating problem with the graphics adapter.

Hello,

First of all, you don't move the iBook in anyway to cause this flicker? (I am assuming not)

Second have you tried to use the F1 and F2 keys to dim the screen to see if the lowest settings stops the flicker?

That looks to me like the screen invertor board needs replacement and if you do find the flicker to stop when you place it on a very low dim settings, then that would more or less confirm the board needs replacement.

When the invertor boards on these start to go, they only get worse. So replacing it sooner than later is best.

MacBook from 2006 - 2008 are known for invertors problems, but unlike the iBook are not that easy to replace.

With your iBook it will take some skill to remove the screen casing to replace the invertor, however there is an art to fixing these back together. If not done correctly then your iBook may fail to close correctly.

They don't cost to much to buy online.

No, but if you put it on the lowest setting (Before you can't see it) does it stop the flickering?

If it stops when the brightness is high or very low, indicates a problem with the inverter board.

You would need to replace accordingly.