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Dual Graphics Mid 2015 15 inch Macbook Pro shuts down whilst booting. It never reaches the full load bar as it shuts down midway, the shutdown times vary. First time seems to load longer than subsequent tries. It still shuts down after: I disconnect the battery, insert a different SSD with MacOS, try re-installing MacOS. Hardware Diagnosis gives me Faulty Airport Card and Battery. Finally, it stays on with no issues in Single User Mode indefinitely, where I am able to run commands fsck etc etc. Other than that it shuts down when trying to boot up normally. With regards. Dennis
Ooops. I forgot to update this thread after getting it fixed. It’s been three years now. The issue was with the battery. I had the dead battery replaced and the laptop operated fine till I sold it a year ago.
Sorry to tell you your dedicated GPU failed. Went you are running single user mode you’re using the built-in graphics services of the CPU (Intel’s Iris graphics). During the bootup cycle the dedicated GPU is enabled which is why it fails to finish booting. Apple has a recall on this issue which you might be able to sneak in on depending on where you live. If you live in the UK then you have a small window here to get the logic board replaced under extended warranty otherwise it’s a new logic board or finding someone who can fix your logic board if they can. Make your way to an Apple Store ASAP! Let them fix this under the extended warranty.
