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Long story short, i changed the thermal paste on my macbook pro as it was running hotter and hotter (as a matter of fact the paste was dry and there were tons of it…). Everything went fine, the display cable was a little stiff and i had to hold it firmly to present it horizontally but nothing scary. I was quite gentle and cautious. When i booted the mac it displayed only blank light (so the backlight is working). The external displays works fine. As in this post (LVDS Cable Issue - Extremely Hot?) i noticed immediately an increase of temperature of the mac (airflow was 60°C) and i shut it down immediately and opened it back. The display cable was very hot, and i disconnected it. I gave a look to the display socket with a magnifier and it looks in perfect condition. I couldn’t spot any visible damage on the motherboard. With the cable disconnected the computer works perfectly with the external display (temps are all fine). Do you think i may have damaged the cable? Are those things notoriously fragile as i wasn’t careless at all. Oh and one more thing :-) the mac now starts itself alone when i plug it in. Maybe this helps to understand what’s going on. Thanks in advance
Ok, end of the story… IT WAS THE CABLE! Today i changed it and all is working again. Not a easy fix for a non professional like me, but i managed to tear the screen down without breaking anything (screen only half an hour in a 75°C oven, the glass came very well with a guitar pick and a small succion cup to help pulling), and put it back together quite clean. I’m very happy, end of a little nightmare… So what i learned: Those cables are fragile as happiness. If you have to disconnect it you have to be extra careful. I advise you to take away the cable holder to have a little more freedom of movement. It’s just a phillips to unscrew and it could spare you ten days of sorrow and an afternoon of wobbling knees! (by the way, excuse any bad english, i’m french…)
MacBook Pro Repair Extension Program for Video Issues Symptoms An affected MacBook Pro may display one or more of the following symptoms: Distorted or scrambled video on the computer screen No video on the computer screen (or external display) even though the computer is on Computer restarts unexpectedly https://www.apple.com/support/macbookpro…
