Chosen Solution
MacBook A1181 Early 2008 Penryn 2.4GHz This question has been answered successfully (screen still dim after new inverter cable AND inverter board) by suggesting to install a new top case. I have installed a new top case but still have a similar, but not exactly the same, dim screen issue. I purchased a broken Early 2008 MacBook, seemingly needing a new Display Inverter Cable and possibly a new LCD and/or Inverter as the display was very dim. Along the way, I discovered that It needed some other repairs. After reassembly and on startup the screen was still very dim and possibly even more so. I can barely see the screen during daylight hours. Here are the components that I replaced and troubleshooting that I’ve done so far: Installed a brand new LCD display, brand new Inverter, brand new Inverter Cable, 2 new RAM modules (2GB each), brand new Optical Drive, a used known working Hard Drive, a brand new top case and keyboard/trackpad and a brand new battery. The dim screen has pale yellow tint. Display calibrations in System Preferences aren’t able to correct the color or brightness. Unchecking boxes in energy saver has no effect. On startup the screen hangs for a bit after the dim gray apple screen with a pale yellow screen. If I view the screen from above at a sharp angle, it is much brighter but still has the yellow cast. When the Macbook wakes from sleep, the screen is very dim but gets slightly brighter after a minute or two. Did I possibly get a faulty new LCD or Inverter? I reset the PRAM and then the SMC but no change in screen brightness. Or, could the Display Data Cable be faulty? I would think that if it were, there would be no data or screen image at all. Maybe a logic board issue? The MacBook is running OS 10.7.5 Lion, 4GB total RAM, 320GB hard drive. I’m ordering a VGA adapter for this machine, so may have more info after I can see an image on an external display. Thank you so much for any insight on this .
Unfortunately, having a bright external display does not rule the logic board out as being a possible fault. the external display has its own power supply and backlight driver. the only data being sent from the computer is image data. So the fact that the external display is bright just indicates that your test monitor is working. As for the fault with your laptop, can you please confirm a few things? In the display preferences of the mac, can you see the brightness adjusting bar, or is it not present? The possible causes of the fault are: Logic Board. Inverter Board. LCD panel. The only reason i’d suspect the cable is if it comes and goes, or if its affected by movement, or you have no backlight at all. if its just dim, i’d look to trace the other items. The logic board provides just voltage. so as long as the voltage is being provided as it should, then it wont be at fault. There is a backlight fuse on the board that protects against shorts or blowouts, but as you are seeing some backlight, that would indicate that the fuse hasn’t blown. I’d look to suspect that you’ve been sold a dodgy LCD initially, as that is the most universally accepted item. The inverter boards are made specifically for this range of mac, so are less likely to be altered or made by 3rd party companies, but LCDs are often built and adjusted by refurbishing centres. Is there a white label on the back of the LCD panel indicating a model number of any kind? that early model of MacBook was usually shipped with one of 4 LCD brands, but the model number will help confirm if its actually compatible with your machine type.
