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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Backlight randomly turns off

The backlight turns off randomly. When I press F1 for a while then F2 it comes back. Sometimes I have to repeat this 4-5 times. Can this be the inverter? Thank you.

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Deck the Halls
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It can be. We first need to assess what's exactly your machine. To achieve that, you should provide us with the last fourth numbers and letters in your Serial Number, that you can easily find in System Profiler, Hardware tab.

However, short story: yes, it may be the Inverter.

Long story, with explaination: That done, usually a failing backlight derives from four causes, and the latter of those is so unlikely that it almost never happens, unless there are some other causes, like water damage and such alike.

I'll order them in order of parts involved

  1. A worn out inverter cable: The cable running from the logic board to the inverter, passes through the display hinges, and in time it wears out and gets pinched in the display. When it happens, the backlight starts to act up, and, usually, jiggling the display up and down restores the backlight for a few seconds, or until the display gets even a small vibration
  2. A failing Inverter: Inverters fail, in time. When it happens, they give short burts of energy, with the backlight working for shorter and shorter amounts of time. Sometimes, when it works, it also flickers, pulsating stronger and fainter. When it's overtly damaged, it acts the way you described
  3. A failing Backlight: The backlight is given by a small CCFL Cold-Cathode Fluorescente Lamp lodged in the bottom part of the LCD panel. Imagine it, for reference, as a tiny neon lamp. As you know, when a Neon lamp degrades, it starts blinking, taking lots of time to reach heat enough to keep working, shutting down at odd times and, when it works, giving out a degrade hue. For CCFL lamps, the hue is pinkish or yellowish
  4. Damaged capacitors on the logic board: As I told, you could chalk it off. Sometimes, the capacitors that push energy in the Inverter cable get damaged. But your machine has less than four years, I'd exclude that.

So, the safest course of action entails changing the inverter, and assess. You may solve everything, or you may need to change the inverter cable too.

I doubt you're going to need a new LCD panel, just the Inverter. If you're unlucky, the inverter cable. That's all.

With your serial number, I could show you the needed parts on iFixit.

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Hi Stefano,

Thank you so much for the detailed reply.

My S/N is : W88443GK5HS

it's a late 2008 white macbook.

Could you please show me which inverter should I get.

Thank you again,

Krisztian

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Apple MacBook "Core 2 Duo" 2.1 13" (White-08) Specs

Identifiers: Early 2008 - MB402LL/A* - MacBook4,1 - A1181 - 2242

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Hi. I've had a few of these in the repair and it was usually a loose wire on the right side of the backlight itself inside the lcd. Just a little soldering job. Good luck !

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Hi. I've had a few of these in the repair and it was usually a loose wire on the right side of the backlight itself inside the lcd. Just a little soldering job. Good luck !

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I've noticed my issue occurs when moving the screen, so loose connection is very likely. Do you know of a guide or images anywhere to show me which connections to check? I'm ok at soldering, but don't know where to solder.

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I have the same problem. Now i changed the inverter and it is still not working. Too bad, so i am gone change the inverter-cable see if it'll work. Thank you goodby

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I'm pretty sure I'm having the same problem. In what you described above it sounds like my inverter has failed. My S/N is: W892804V9GV

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hi i'm having the same problem , can u tell me which part to replace my serial nos. W87321D1Z5X

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I just added my email address to the "I HAVE THIS PROBLEM TOO" list.

Does anyone know if this problem also happens when using an external monitor? I just tried using the Mini DVI to VGA adapter and a friend's monitor, and it works fine, video never goes out. Also, the failing backlight problem does not seem to happen when I have the adapter plugged in, whether a monitor is connected or not. ???

Furthermore, about 25 minutes ago, I unplugged the VGA adapter and have been using this MacBook without a hint of the backlight problem. ???

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Could you (or anyone ) please PLEASE reveal the formula or procedure whose input is the serial number and whose output is the various part numbers of the inverter and inverter cable (and any other bits of this assembly).?

It's not possible sustainable to imagine that you will be able to do the lookup for everyone. It's fabulously kind what you've done so far. I thank you in advance for doing this last bit as well.

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krisztianvass will be eternally grateful.
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