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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Is it really the inverter board?

I've read many questions, answers, etc. dealing with display inverter problems, whereas in most cases the display beacklight wasn't working at all or was flickering because of mechanic problems.

So I have almost the same problem with one difference: in general my backlight is working, but only at lowest level. As soon as I light it up with F2 button, it breaks down. If I bring it back to zero (with F1) and then 1 up, it comes back.

When the laptop wakes up from being closed before, it usually as well breaks down and needs to be resetted to lowest level (as explained before).

So I'm curious whether this could really be the inverter, as most people say that a bad inverter causes completely dead backlight. And it doesn't seem to be a mechanic (cable) problem, as it has nothing to do with the screen angle. But: sometimes when resetting it from 0 to 1 it is flickering and crashing then again, so I have to try the described routine for 3 or 4 times until it works.

My model: http://www.ifixit.com/Info/ID-your-Mac/3...

Meanwhile I already opened the macbook to check if I can see any cable damage or loose connectors - nothing.

So what do you think: is it really the inverter? Or, as it seems to be dependent of F1/F2, rather software? This is a 2 GHz Santa Rosa machine.

THX a lot in advance for any help!!

Answered! View the answer I have this problem too

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ok guys. so i finally got to buy a new inverter board from ifixit and ... it didn't work :( still the same problem ... althought now after several weeks of driving my display on lowest level i again can use it on somewhat around mid level without suddenly losing backlight. my next try will be with a new cable :( 55 bucks for nothing..

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i have the exact same model and exact same problem

let us know if replacing invert worked for you!

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I suggest you start your own question as we've had no response from the poster for a week.

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yo, sorry for not answering so long! as posted above, i'll get a new inverter board as soon as i have some spare money. i'll keep you guys updated what's the result!

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IMO the problem could be the top case, the inverter board or the logic board. I don't think it could be a software issue but you can easily test it by booting the MB from another source than you HD OS (by using your installation disk, an external HD, etc).

A tech could test the logic board inverter socket voltage with a multimeter or remove the top case and boot the MB directly from the power contact points on the logic board and check with a usb keyboard if the brightness works adequately.

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sorry for not answering so long & thx for your tips so far! i guess as soon as i have some spare money, i'll have to get a new inverter board. maybe it works. any suggestions where to buy an inverter board? here at ifixit it's about 50 bucks, which is cool, but it's used and has warranty for 6 months. i mean i don't want to need a once more new board in even 12 months.

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With the inverter out you will still be able to discern the desktop, so it doesn't go completely black. Here's how to install the inverter: MacBook Core 2 Duo LCD & Inverter A1181 (fast method) Replacement

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true, of course i still see in a certain light angle the desktop, as it is not the lcd, but the backlight. whats so strange is that the backlight itself is working. but it is only working at lowest level. so i have a working inverter, but it is somehow not able to make a brighter desktop than on lowest level.

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The screen inverter is a circuit board that passes the power current from the body of the laptop computer to the LCD, powering the backlight and allowing you to see the images on the screen.

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sorry for not answering so long & thx for your tips so far! i understand what you said, but i'm still curious because on lowest light intensity i can work as long as i want. only if i light the screen up more, it breaks down. so in this case the screen inverter board would have problems with higher voltages or what chould it be? i mean: is this possible that an inverter board is not completely broken but still working on lowest light level?

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most times you have to search for the best prices, just like cars or groceries. I like iFixit parts because I know they test them and that entails more expense. Finding new parts is almost impossible. Try this:http://www.gainsaver.com/catalog/Detail....

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It is very likely the CCFL in the screen. Not recommended for the novice but if you take apart the LCD panel you will probably find a black soot like substance where the wire connects to the CCFL (the pink or blue or white wires to the actual bulb itself) This comes from running the high voltage electricity through a bad connection from the wire to the bulb. It is creating a high amount of resistance that inverter's safety features are detecting and then shutting it down. If you can successfully extract the bulb it is typically as easy as cleaning up the area and re-soldering the wire / wires. But the bulb is very fragile and i believe contains mercury or something else very not good for you, so its a bad to break it open. Obviously cant guarantee that is the problem but i would be quite surprised if it wasn't.

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thx senordingdong!! the first answer really leading away from that inverter stuff... as said: i have a new laptop now, but as soon as i got some spare time, i'll open this one again and check the ccfl bulbs.

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More than likely you got a bad inverter cable. When the CCFL is going out because the gasses inside are used up it produces a redish hue to the screen. If the connection is bad to the CCFL or the wires have been compromised between the bulb and the inverter there is a hummm or buzzing sound caused by the 600 volts going through them. txt, you have pointed out that closing the lid to put it to sleep causes the problem to manifest. When you close the lid you twist and flex the inverter cables.

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I have this exact problem also. No chg with LCD position. 2 replacement inverters caused rt side to be dim, lft to be dark. No ability to chg brightness, unlike the orig inverter which always worked by hitting F1 several times then F2 once and backlight would come on - for only a short while. Assumed it was a bad inverter and manuf. shipped free replacement, which behaved as first so I'm doubting inverter. I ohmed out the input cable and it is good. I completely disassembled the LCD after reading your post, exposing the layers of the backlight panel and separate LCD. Very difficult and not recommended. I saw zero discoloration and THERE IS NO BULB, the Mac backlight is an electroluminescent panel.

There are 2 potentiometers on the original inverter, adjusting them seemed to make no difference. Before breaking the seal on them I measured the output voltage which exceeded 700 volts AC at the 3rd from brightest level. I have not yet measured the output to see what effect the potentiometers have on it.

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I may recommend to my client to buy yet another inverter from another source, such as iFixit at triple the cost, but with a garantee of functionality.

The only other conclusion I can draw from this difficult but relatively common problem is the main logic board which provides the power to the inverter bd is where the problem exists. If so the problem is probably prohibitively expensive to repair.

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Hi I have the Core Duo (2006 in Black) and had a similar problem, although I did have a bit more life in my screen than you. I replaced the inverter and it made no difference.

I eventually fixed it by simply unplugging the inverter cable from the logic board and re-inserting it. I also but a small square of gaffer tape over the foam square which is stuck to the topcase and appears to be there solely to put pressure on the inverter cable connector.

It has been working fine since, and doesn't flicker at ANY screen brightness, which is an improvement on new.

I have heard of others fixing the problem by replacing the cable that runs from the logic board to the inverter too.

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Txt, I have exactly the same model/issue also, did you end up replacing the cable as well as the inverter board? Did it work? I'm interested in hearing what works before I strip the machine down.

Thanks

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unfortunately there's no success until now & i'm still stuck with it. first i bought an inverter board from ifixit - didn't work. then i bought an inverter board with cable from ebay (to get the cable) - tested both & again didn't work. so: either the cable from ebay wasn't working or the problem generally lies neither in cable nor in inverter board. at the moment i don't have enough time to get it done (while using a second display for working), but i guess as soon as i'm done with my diploma, i'll bring it to a repair service. good luck for you!

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Is it possible that the inverter is not plugged in correctly? I see several other posts that say that they have a dim LCD after replacement and one person answered that the inverter cable was incorrectly plugged...

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thx tscott! but, as said: i tried it several times. sure it still could be that it isn't plugged correctly. but as this was one of the first things i've checked, i don't think it is the case. i bought a new mbp meanwhile and will wait for the next opportunity (financially) to bring this display to a repair service.

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txt will be eternally grateful.
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