Model A1181: 1.83, 2, 2.1, 2.13, 2.16, 2.2, or 2.4 GHz Core 2 Duo processor

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LCD Panel backlight not working properly

My LCD backlight is having some major trouble : if I put maximum brightness, the backlight goes off, I can only use the minimum brightness setting. Even then the light will go off after a certain time or while tilting the screen.

I can manage to turn it back on by switching on and off the brightness (with F1 and F2 keys) but either it takes many attempts or the screen lights partially or not at all.

I already tried replacing the inverter and the inverter power cable with no success. I guess the problem is the LCD panel itself or the cables going from the inverter to the LCD, but those can't be replaced without replacing the whole LCD, right?

Does all this make sense?

This is a 2.4 GHz (Penryn) machine.

Thanks for the help!

Answered! View the answer I have this problem too

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hook it up to an external monitor to isolate the problem and let us know the results.

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Defective CCFL backlight may have the following symptoms: Screen flashes on red/pink and goes off. Picture stays on in red and slowly be come normal. Picture flickering with dim display. Picture flickering on and off. All these symptoms indicate that the LCD backlight lamp (CCFL Lamp) has reached the end of its life.

If this sounds like it might be your problem, refer to the links on this question for how to replace the CCFL backlight and sources for the parts: CCFL Backlight Repair and Information

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I find it unlikely (though not impossible) to be the LCD panel itself. Excluding more modern "LED" displays, standard LCD display backlighting is controlled by an "inverter". This may burn out without showing any signs of damage and can happen quite suddenly. The issue here is that the problem is intermittent and seems to be aggravated by movement.

The most likely cause for this, based on your symptoms, is the cable connecting the display to the logic board. The secondary cause could be a failing inverter, though those usually either work or don't. If neither of those fix the problem, I'd consider replacing the LCD panel, but that should be a last resort.

I hope this helps!

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Yes, try connecting to an external monitor. If it's bright on the external, then the problem lies in your LCD panel. If this is the case, then the entire panel will need to be replaced. It seems like a connection somewhere in the panel might be shorting out, which explains the problems you describe. Since the components are in the display itself, it's not possible to repair it. I'm not sure if you'll be able to get a replacement panel for you MacBook, but you can look around. Replacement involves getting the entire panel out from the bezel, which can be a challenging proposition, so if you want to attempt it, be very careful and make a note where the screws go. Good luck!!!

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just a query.. I've recently seen backlights for LCD's being sold separately.. if you can buy them, can't you just replace that part? or am I being silly?

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How the external monitor would help my case? I mean, it's only to isolate if the problem is with the backlight or the logic board? I already know the logic board is ok, the data displayed is fine even when the backlight if off and the computer works fine.

anyway, I don't even have the cable that you need to hook to an external.

Thanks for your advice!

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Replacing CCFLs, however, can be difficult. Since they're mounted behind the panel, removal and replacement can be a challenge. Getting one can be difficult as well, but make sure you get one made for the panel or it won't work. It might be better to change out the entire panel than replacing the CCFL.

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mirze will be eternally grateful.
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