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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No Backlight: Inverter or LCD Bulb?

I am having issues with the backlight on my macbook. I've done some research and it seems like it is either the inverter (or inverter cable) or the LCD bulb itself.

I have one additional finding that I was hoping is able to distinguish these two problems. When I first started experiencing problems with the backlight, I was able to use the brightness keys on the keyboard to adjust the brightness and get the backlight to start working. When the screen was black, I'd adjust the brightness to the lowest setting and then adjust it up one. In must cases the backlight would come back on, but other times it would flicker and go back out. When it came on, it would stay on as long as I left it dim and I was still able to use the screen normally. However, if I tried to adjust it to the brighter settings, it would flicker and go black again.

I was able to do this for a few months, but now the backlight is out completely. I am wondering if this descriptions sounds more like the bulb going out or a failing inverter?

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Hi! Thanks for the detailed description. First, I would reset the PMU/SMC and PRAM, and verify that the issue still exists afterward. By "backlight out completely" I am assuming you mean that you still see a faint image.

If changing the brightness setting restored the backlight, and it flickered while you were NOT flexing the screen hinge at the same time, that's a very strong indication that the screen itself is bad. A flaky inverter cable will usually act up when the screen hinge is moved (because it's crimped in the hinge), so being able to restore the backlight with the brightness controls would tend to rule out the inverter cable. The inverter itself is almost never bad on A1181s. In rare cases the electronics on the board related to the backlight go bad, but that's not so common.

So again, in your case I'd rank the components in order of likeliness -- screen, inverter cable, board, inverter. The inverter cable is about $20 on eBay (and so is the inverter), so some people would opt to swap that out first, just to rule it out before buying a screen.

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Thanks for the suggestion. I also suspected that it was the LCD itself. However, like you said, since the inverter is so much cheaper, I tried it first just to be safe. It did not solve the problem, so I just ordered a replacement LCD screen.

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New LCD screen installed and working like new! Thanks again for the help.

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@rdklinc: I cannot understand how the LCD panel itself can be faulty in this case which is clearly a lightning issue. There's no relation between the inverter cable/inverter board/backlight assy and the LCD electronics. The lightning system is all driven by the logic board and the inverter board. Past the inverter output there's no electronic only a connector, two cables and a backlight bulb.

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