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Model A1502 / 2.6 GHz (Turbo Boost up to 3.1 GHz) or 2.8 GHz (Turbo Boost up to 3.3 GHz) dual-core Intel Core i7 processor with 4MB shared L3 cache.

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no chime / unresponsive to entering recovery mode etc after sudo nvram

I upgraded my A1502 with a NVMe/PCIe SSD (version without adapter which fits directly). was working fine had some sleep/wake failures sometimes so I read through some forums and tried some pmset adjustments in terminal

After auso nvram enable-legacy-orom-behavior=1, nothing worked anymore.

  • SMC/NVRAM reset does not seem to do anything
  • Booting from old original SSD with Catalina which was working perfect does not work
  • Entering safe mode/recovery mode does not work
  • Completely removing SSD and only starting from catalina usbdrive doesnt work

I get no chime nothing, just flashing question mark folder after a while. Is my logic board fried or whats up?

Answered! View the answer I have this problem too

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Who's SSD did you use? Make, model & size.

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indem 512gb pcie nvme.. but shouldnt make a differnve since i tried booting also from the original apple ssd which is sill working fine. but also non responsive?

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Your previous question Upgrade to 512gb mSATA/NVME drive is not recognized did you get any help from Indem?

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yea they helped, worked fine except some sleep/wake failures from time to time

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It seems you bricked your Mac for good. Where did you dig out that "auso nvram enable-legacy-orom-behavior=1" command from, just out of curiosity ?

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@dreiszt Either you were tremendously brave or too excited for having found a solution that you forgot to go through the comments..that guy apparently helped bricking a number of machines..

Try what @danj recommended with Apple. If you have no luck with that, your last resort would be finding someone into component level repairs who can replace your Efi IC with a clean one.

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Another good reason to stick with the real Apple SSD or one of the major replacement drive makers OWC or Transcend.

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@danj If this would be the alternative I would agree. Another lesson I'd take from this, is beware of the random youtube wonderboy.

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Give this a try How to select a different startup disk. You’ll need an external bootable drive to use.

You should also be able to see the drives via the Startup manager pressing the Option key when you restart your system.

Reference: Mac startup key combinations

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i made a bootable drive. key combinations to enter are unresponsive.

also tried original ssd, wont boot from there either; but is working fine in another macbook.

efi bootrom seems to be bricked? :(

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Yes the EFI is damaged. Time to visit an Apple Store with the original SSD re-mounted. I would not offer to much info. Let them figure it out. I would only say it messed up during the OS update process.

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I believe the EFI is damaged. You need to visit an apple store to check whether it can be fixed.

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I had the same issue. 2 days spent on it.

The MacBook Pro started with black screen, no chime, no Apple logo. After some time it displayed the ? folder.

I tried all the options, but no success, I eventually succeed by doing the NVRAM reset buttons (cmd-opt-R-P) for ALMOST 5 minutes and suddenly heard the chime (I press few time the power button to make sure the system started and continued to press the other 4 buttons). To conclude, I now have Catalina on my MacBook Pro retina 13' early 2015 128GB!

I've upgraded to a Samsung 970 EVO SSD. However, I learned the hard way that it must be via macOS Mojave.

You MUST have a bootable Mojave disk and once the system restart, you should erase the Samsung 970 EVO to reformat it and only then you can restore from backup.

Hope it helps!

BTW: Since the was issue was with Catalina I moved back to my original SSD.

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dreiszt will be eternally grateful.
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