Screen Backlight Not Working! Need Advice!
Macbook Pro 15 Inch A1286 October 2008
So, it appears as though my Macbook Pro 15 inch screen LCD/LED backlight has stopped working. I have done all the basic stuff, reset the Pram, SMC etc.. No changes. I can indeed see the screen working by using a flashlight, or shining a light through the Apple logo. After an extensive search online to possible solutions, I have come up with 3 that stand out so far.
1- The screens data cable from the motherboard to the screen has gone faulty. I have ordered this to try since it is the cheapest solution to start with.
2- The LED Backlight is actually fried in the LCD screen itself. Replacing the LCD is the next cheapest solution to try since ebay is crawling with these.
And finally, the one I'm having an issue with...
3- The inverter for the screen. From early 08 models (all aluminum) to late 08 (Unibody, which is mine) apple changed how the screens were powered. From what I can tell, they either did away with the inverter or put it somewhere else for the screen. Some people say there is one on the Motherboard, others say its not needed due to the LED backlight and how it works power wise. Maybe Im not hitting the right sites to find this info, but after 6 hours of looking, you get a little frustrated.
So my question is, is there an Inverter? And if there is, where did apple put it? And can it be changed out for a new one? Or does the entire motherboard need to be sent out? If it needs to be sent out can anyone recommend a reliable company here in the states I could send it to? I refuse to take it to apple as it will be nothing but costly through them. I have some repair experience with the older macbooks, but unfamiliar with the unibody's and taking them apart. So I am hunting for info before tearing into it.
There is no inverter at all in the Unibody Macbook Pros. They use LED bars to light the display, instead of the older florescent tubes. Inverters "ramp up" the power from the circuit to provide higher voltages that are required for powering florescent tubes in CCFL LCD type displays. (http://en.wikipedia.org/wiki/CCFL_invert...)
If you have worked on older MacBooks and feel comfortable soldering on the logic board, I would first look at this thread:
I know it is very long, but I used it to bring my mid 2009 pro back to life!!
The problem for me, and many others, was a blown fuse found in the display circuit. It is tiny (2mm X 4mm) and if blown will cause the backlight to not power on.
There are many companies on eBay that do the repairs, but at least test the fuse first!!
It might be scary to think about having to solder on the Logic Board, but read the thread, many of us have had major success!!
hope this helps!