MacBook Pro 15" Mid 2014 Randomly Hangs With Black Screen

Number:rdar://46161812 Date Originated:2018/11/19
Status:Open Resolved:
Product:MacBook Pro 15" Product Version:Mid 2014
Classification: Reproducible:Sometimes
MacBook Pro screen sometimes goes black, and refuses to wake. The only remedy is to press the power button. Sometimes the fans are very loud, but the computer is unresponsive.

Steps to Reproduce:
Use the computer. Today I have been using Mathematica and Spotify.

Expected Results:
Computer keeps working.

Actual Results:
Computer randomly hangs with a black screen.
Sometimes I can go for 6 to 10 days without any issues.
Today (19/11/2018) it hung multiple times in a couple of hours.

MacBook Pro (Retina, 15-inch, Mid 2014)
MacOS 10.13.6 (17G65)

Processor: 2.2 GHz Intel Core i7
Memory: 16 GB 1600 MHz DDR3
Graphics: Intel Iris Pro 1536 MB
Serial Number: C02PN1A7G3QN

Additional Notes:  There are two main theories about the cause of this bug.

1. There is a bug in /System/Library/Extensions/AppleThunderboltNHI.kext Disabling this is supposed to fix the issue. (I have now done this, and will wait to see if the issue manifests again.)
See here: 

2. The CPU is entering an unstable low power state, which triggers the crash.
See here:


Update. This issue continues to manifest. Apart from asking for a sysdiagnose, I have had no response from Apple.

To achieve some stability, I can confirm that the following steps work most of the time:

  1. Reboot into recovery mode
  2. Open a Terminal
  3. Disable SIP by running csrutil disable
  4. Restart into normal mode
  5. Move /System/Library/Extensions/AppleThunderboltNHI.kext to /System/Library/Extensions/AppleThunderboltNHI.kext.bak
  6. Repeat steps 1-4, but with csrutil enable
By daviewales at April 11, 2019, 2:38 a.m. (reply...)

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