Chosen Solution
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!!
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.
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
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.
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.
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
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…
