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The screen on my MacBook is completely black after I boot it up. I tried different trouble shooting methods I found online (resetting PRAM etc) but none of them worked. I then read something that suggested shining a light through the apple on the lid. I did this and I can then see the centre of the screen light up dimly. In this case what exactly would I need to do to repair this?
What you are looking for when you shine the light is to see if you can discern the desktop. At this point you need to determine where the failure is. Hook it up to an external monitor to see if the GPU is generating a video signal to help isolate the problem. UPDATE Reseat the display to logic board connector and inspect for anomalies. See step #19 of this guide. MacBook Air 13" Mid 2013 Display Assembly Replacement
Common issue corrosion on pin 5 of the backlight driver.. Could be from liquid damage or could be from the moisture in the air. You will need to find someone that does board level repair to do this. The chip is simple to change for anyone that knows what they are doing.. You may been a wire run under pin 5 as the pad is usually destroyed.
