Because '''it's not designed to be opened past 90º''', ''(very few laptop models are so designed, none of them Apple) ''you've shorted, pulled, or broken the connections/cables that run through the hinges to the display. I''f you're lucky you may be able to open the machine and reconnect them. ''If you're unlucky you'll have to replace hinges (clutches in Mac vernacular) and other cables or parts, up to the logic board or display itself. To DIY you'll need to get the proper tools to open the laptop ''- every job is easier when you use the proper tools.''
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